Yes, but what I'm arguing against is the idea that motivated some of the early modern philosophers - they took seriously the problem of general foundations for knowledge, they thought you actually do NEED such a general foundation otherwise normal inquiry can't proceed properly. That, I think is wrong, and the truth is somewhere inbetween - it's a good exercise to examine our presuppositions generally now and then, sure, and as you point out it's something that arouses curiosity anyway. But it's not something that's necessary (such that if we don't do it, we must down tools and resolve the problem before knowledge-gathering can proceed any further). — gurugeorge

I'm not sure how many of the early moderns thought that. Hume certainly didn't, since he thought no such foundation was possible and yet still wrote on history. Descartes didn't think so either. He just thought that if he could secure such a foundation for his fundamental metaphysical ideas, it would give those ideas a huge advantage over alternatives; it would make them stable and lasting. It wasn't that he thought you couldn't do inquiry otherwise; the Aristotelean program before him had done so and he knew this. He just thought it would be better to have the foundation in place, and that still sounds right to me.

One criticizes religion for being question-begging on specifiable, verifiable grounds that are fairly close to the surface. In order to do that, one doesn't need to have examined one's own presuppositions - although that can be done, it doesn't affect the "bite" of the criticism of religion on its own terms.

e.g. one doesn't need to have indubitable foundations for knowledge in general to criticize a religious argument for taking it for granted that "everything must have a cause." — gurugeorge

Why can't they take fore granted that everything must have a cause? Why do they need to prove this principle using premises only a religious sceptic would accept? Why can't they just assume it to be true and get on with Theology? Isn't that just what we do with something like 'sense perception is reliable, on the assumption that no non-question begging rationale for that belief is needed? What can the criticism of the principle of sufficient reason amount to if that very same criticism can be levied against 'sense perception is reliable'?

Moreover, why can't the religious believer just say, as Plantinga does say, 'the cognitive faculty which produces belief in God is reliable', and take this as an assumption which can't be provided any non-question begging rationale? And when someone dares question this axiom of theirs, why can't they just say 'I don't need to put my religious belief on any more secure foundation'?

we have an ongoing model of the world that we ongoingly juggle into existence, which is the thing we believe in and trust, until such time as an anomaly crops up and we have to revise the model. That model is always, in its most fundamental nature, conjectural — gurugeorge

Doesn't the Norse Pagan have that? He has a model of the world which he ongoingly juggles and which he trusts, until such a time as an anomaly crops up. He has no way to prove to you that he will go to Valhalla on death so long as he dies a warrior's death. Its just part of his model, like 'sense perception is reliable' is part of ours. What's the difference?

Another way to appreciate this last point is to appreciate that we don't have an ongoing model. each one of us has our own on going model which is different to others - and sometimes radically so - and all of them are conjectural on your understanding. But this, surely, makes every model, no matter how seemingly absurd, equal in authority to every other.

PA

To say that an actual 'evil demon' was responsible, this time, for making the laptop pop back into existence in a completely harmless way just like he did last time and all the hundred times before that is not to describe an 'evil demon' by the public meaning of the word at all. — Inter Alia

Perhaps the description 'evil' is misplaced then. Try instead, 'deceiving demon'. He certainly does deceive, since he fools everyone into thinking that the objects they perceive also exist unperceived when they don't.

Whilst we cannot say what causes the laptop to appear to us again every time we open our eyes, we can say that the cause is mundane, benign (or at least disinterested), extremely consistent and unobservable to us or our machinery. That rules out certain things by their public meaning. Demons are one, God is another, the mad scientists/brain in a vat a third. Oddly, a matrix-like simulation is not ruled out by this requirement as its very purpose would be to be mundane and consistent, so it's not a complete argument for realism so much as an argument against certain forms of anti-realism. — Inter Alia

I would add 'deceiving demon explanation' to the simulation explanation insofar as both are mundane and consistent. Is it right that you think there is no reason to prefer Realism over these kinds of mundane and consistent alternatives?

PA

It just goes back to my original points re. doubt - the reason you dig back behind presuppositions in the ordinary way of inquiry is when and if you have some anomaly or some other reason to doubt. Some hint from experience that things may not be as you think they are. That's the home of doing something like "examining our presuppositions." — gurugeorge

Right, ordinarily.

Other than that, I don't think there's any general need to have "indubitable foundations" - so it's not so much that I don't think any non-question-begging rationale can be had, it's that I wonder at the purpose of the exercise of looking for some non-question-begging, over-arching rationale, given that the usual process of knowledge-gathering doesn't require such things. — gurugeorge

I have some difficulty with this. In a way, there isn't a need for all sorts of things that we insist on doing. There is no need to have literary critics, but we have them. There is no need to figure out the history of the romans, but we try. There is no need to figure out whether the universe is temporally finite or eternal, but we try. What drives all of these inquiries isn't some desperate need to solve the problems, but curiosity. Equally, one might simply be curious whether a non-question begging rationale can be had for all of what one presently believes. It might be that there is no dramatically important reason why we must have that rationale; its just that one wants it, or wants to see whether it can be had. That's how it is for me anyway.

On the other hand, the question whether the rationale can be had seems important for the following reason. Many of us often assume that some beliefs are silly, or absurd, or unreasonable, or just plain crazy. We often criticize rival systems of belief on that ground. Perhaps its Christianity, or Islam, or Hinduism, or the old Norse or Greek mythologies. Perhaps its belief in the immortal soul and the afterlife. These are just the examples that come to mind and which many people often dismiss for being rationally sub-standard. When you look into those criticisms, what they often come to is the criticism that no non-question begging rationale can be given for those beliefs. But how silly are these criticisms if we can't provide a non-question begging rationale for our own beliefs when it comes to a persistent sceptic? If we can't provide a non-question begging rationale for even the simplest things then this kind of criticism, which is prevalent in culture, is completely unfounded. Many philosophers today don't see the point of looking for a non-question begging rationale for what they call 'common-sense', but they fail to see the point that if you can't do it, a certain kind of rational criticism on which we rely all the time turns out to be a hollow game.

PA

So whilst both the Realist and the Idealist have the same public hypotheses they are effectively the same in the field of public discourse. — Inter Alia

Now I see what you mean by this. Thanks for the clarification.

I don't know of any examples where the 'evil demon' explanation has yielded any new hypotheses that have proven useful. — Inter Alia

But this is less clear. I thought you said that the evil demon explanation and the Realist explanation have the same hypotheses. So if Realism has useful hypotheses so does the evil demon explanation.

I know plenty of new hypotheses (the whole of science) which have resulted from believing in a Realist explanation. — Inter Alia

Could you give a specific example of a hypothesis which only results from Realism and not the evil demon hypothesis? (Again, if what you said above is right, there are none, and so I am puzzled).

(usually some variant of "you should therefore let me do whatever my book/god/guru says without judgement") — Inter Alia

I have never met an Idealist who takes that line (to be sure, I haven't met many Idealists at all!).

PA

There are some difficulties in what you said, or perhaps just difficulties in my understanding it. You say that 'when you are talking about meaning, you are talking about collective utility', and you give the example that it is collectively useful to agree that the word 'tree' means a specific kind of object and this allows us to 'use it in conversation'. I agree with this, but what is the relevance? Here is what you say:

It's like that with the 'cause' of a perceived effect it could be physical or it could be an evil demon, and whichever you believe may have subjective meaning to you, but it is as pointless as a personal definition of the word 'tree' in public discourse because it has no shared meaning. If 'evil deamon' and 'physics' have exactly the same effect then their shared public meaning is the same. It doesn't seem the same because actually when we think of an evil demon we're certainly not thinking of something like the laws of physics, we're thinking of something like an malicious person, but with horns. But we've just established that if there is an evil demon doing all this he's not like that at all, he's extremely consistent, apparently benign (or at least disinterested), just like the laws of physics are. — Inter Alia

We need to be very careful not to fall into the veil of perception doctrine here. Talk of 'what causes the perceived effect, a physical object or a demon?' makes it sound like what we perceive is an image which is caused by one of these two; the veil of perception doctrine. I am presently perceiving something which I normally call a laptop. Does it exist unperceived? If the evil demon hypothesis is true, it doesn't, since the demon just puts these things before me like a show, and 'turns them off' when I am not watching. Your objection to the evil demon hypothesis was that is not 'meaningfully different' from the Realist hypothesis that things exist unperceived. My answer was that there is a clear difference in the things postulated by each hypothesis: the Realist posits unperceived laptops, the evil demon hypothesis posits an unperceived evil demon. Your thought is not that because they have all of the same empirical consequences, there is no significant difference between them. Is that right? I took that from your use of words like 'pointless'. You say further that the two hypotheses have 'the same public meaning'. I'm not sure what a public meaning is and how it is different from meaning simpliciter.

I think at last we can locate the substantive disagreement between us.

it's not like the Cartesian excursion is fruitless, because you learn what not to do, what's a waste of time - the problem is when you're theorizing philosophically but you think you've got something more objective and more indubitable than you had before, when really you're just getting into even murkier territory where we don't know what up or down is (metaphorically speaking). — gurugeorge

I don't think there's any such thing as a non-question begging answer as to what it is you're seeing when you're looking at matters from a truncated, phenomenalist point of view either. It's even more mysterious, so it can't be a purifying foundation. Isn't that what Carnap found out, after all? — gurugeorge

Our disagreement is that you don't think any non-question begging rationale can be had for our beliefs, at least not if you push questioning far enough back. You seem to think this is obvious. I'd be interested to know why you think it is so obvious, and also whether you would be prepared to characterize this as a kind of Pyrrhonian Scepticism, since it is just what those ancient sceptics used to maintain?

PA

I see your point. The evil demon hypothesis is one which is empirically indistinguishable from the Realist hypothesis. I agree with you on that, since they both have all of the same predictive consequences. You infer from this that the two hypotheses aren't meaningfully different and that it is just a verbal matter of whether to say that, for example, the laws of physics are the laws which govern the behaviour of the demon, or not. 'We may as well have a demonology department' and it would be just the same as our ordinary physics department. I agree with everything except your inference that the two aren't meaningfully different. For you to infer that from the facts which you have mentioned, you require the premise that two hypotheses are meaningfully different only if they have different empirical consequences, and this amounts to the premise that two hypotheses are meaningfully different only if they predict a difference in what we perceive.

That premise is a form of Verificationism, and I can't see why you would accept it.

Excuse me for only extracting parts of your post for discussion. All of it is excellent, but I fear that each of our posts will spiral into large treatises before long! I will try to get to the heart of our disagreement.

But then what, in what way is it being used? When are you applying or using "schmexperience" properly? How would you know? What is the nature of the "self" who's "having" "experience" in this new sense? Or does schmexperience not have a haver? Or is the haver of a different kind? If so what? — gurugeorge

Say that X is schmexperienced if and only if X is given to conscious awareness in such a way as to provide a sensible answer as to why the subject should believe that X.

So I might schexperience a patch of red only if the redness is given to my conscious awareness in such a way as to provide a sensible answer as to why I should believe that there is a patch of red. Of course the notion of 'given to conscious awareness' is somewhat metaphorical, but I don't think this is a barrier. Anyone can get a handle on what it is for something to be given to consciousness just by reflection on his own present awareness. One might doubt that anything ever is given in this sense, but that does not mean that the concept is meaningless; just that it is not an accurate description of anything.

"In another sense" - in WHAT sense, precisely? What is this "seeing" you're talking about?

Normally seeing implies or presupposes a bunch of physical-world-story stuff. But if you're not implying that, then what is the testable content of this "seeing", what are the conditions for whether one is "seeing" in this sense? When can one correctly be said to be "seeing" (shcmeeing? :) ) in this sense, and when not? — gurugeorge

One is 'seeing' that X in the sense I have in mind only if X is given to consciousness in such a way as to provide a sensible answer as to why the subject should believe that X. That is when one can be said to be seeing something in my sense; when the thing seen is so unproblematically available to consciousness as to preclude any further sensible doubt about whether it exists. Again, maybe you doubt that there is anything which is available to consciousness in this way, but that doesn't speak to the meaningfulness of the concept.

No, rather it's saying that bracketing all presuppositions isn't necessarily the best way to build an indusputable system of philosophy. We already know how that ends up, it ends up in solipsism with a thing that has no name and character "experiencing" various things that may or may not be the case. Yes, a very solid foundation for a philosophy. — gurugeorge

Perhaps you are right, but I don't think its anywhere near as clear as you make it out to be. Many philosophers have this habit these days. The habit of just saying 'oh its just obvious that bracketing all presuppositions leads to solipsism' and then adding 'such a philosophical method is useless'. But very rarely, if ever, does anyone take the time to look at the matter in detail. You seem to be doing just the same thing here.

If so, then you should have no problem with the camera test. — gurugeorge

My issue with the camera test is that it presupposes that Realism is true. No one who didn't already accept Realism would accept the camera test.

Again, given =/= indisputable. "Given," like "experience," etc., etc., already carries some baggage from the larger world. "Given" in distinction to what? — gurugeorge

Given in the sense of, as Stace puts it, 'logically given'. Indisputable in that what is given provides a satisfactory, non-question begging, answer to the question "why should I believe that?". What is given is the ultimate starting point for argument.

But you already knew that nothing is indisputable, that's already built into the ordinary way of looking at things. You just need a reason to dispute, but staring at your sensations and dreaming up alternative logical possibilities doesn't give you a reason to doubt the ordinary application of some ordinary concept. — gurugeorge

I reject the doctrine that there is an 'ordinary way of thinking' with respect to pretty much anything. Everybody thinks differently, and in this case there may, for all I know, be very great differences in what people take to be indisputable. In any case, that you ordinarily think that nothing is indisputable is not a good reason for you to suppose that it is true. What is ordinarily thought is just a matter of what you have been conditioned by culture and evolution, together with your own individual background, to believe.

It is worth pointing out, since you have many conceptual doubts, that the sense of 'indisputable' I have in mind is that something is indisputable if and only if there is a non-question begging answer to the question as to why it should be believed. Do I ordinarily think that nothing is indisputable? No. I was initially inclined to think that a lot of what I believe is indisputable. Perhaps I am wrong, but that is what I thought.

To shift the discussion slightly, your posts always presuppose that there is such a thing as 'our ordinary concepts' and that is your fixed point from which you argue that my position warps those concepts into meaninglessness. I reject the idea that there is any substantive body called 'our ordinary concepts'. People sometimes have the same thing in mind and use the same word to represent it, but quite often people have quite different or slightly different things in mind whilst using the same words. I might use the word 'knowledge' and mean by it something like indisputably true belief, but you might use that word in a very different way, even though when talking to each other, we never notice that difference in our communications. I also think that most people have no very precise concept at all for the concepts which are discussed in philosophy - knowledge, reason, space, time, morality, perceive, mind, physical, and so on, and because the concepts are so vague ordinarily, I think it even less likely that people often have exactly the same thing in mind by them, even though this goes unnoticed in every day communication.

From your perspective, the ordinary is the paradigm of meaning and it isn't clear how any non-ordinary concept is meaningful unless it is very carefully explicated. But as I see it, its the ordinary which is vague, full of variation and inconsistency, and in desperate need of explication. I guess I'm an Aristotelean or a Carnapian, and you are Wittgensteinian.

PA

If the Idealist has the concept of these two cars and the idea that the one leads to the other, then he is in no meaningful way any different to a Realist — Inter Alia

It seems to me that he is meaningfully different and that you recognize this. The Realist postulates that these two experienced cars are numerically the same car which persisted whilst unperceived. The Idealist denies this.

We too postulate a perceived car and an impacting car. We then come up with a theory as to why these two cars seem to be so inextricably linked, that theory is that they are the same car. Its a damn good theory too, it does exactly what a theory is meant to do in that it provides us with virtually 100% successful predictions, now why would we change that process in favour of one which gives no explanation as to why the two cars are inextricably linked. — Inter Alia

I think you are right that this kind of argument is the kind which Idealists of the past typically missed. What leads Stace, for example, to Idealism is that he thinks you can only infer that things exist unperceived either by deduction or enumerative induction. He completely fails to see inference to the best explanation.

The Idealist is indeed offering no explanation at all, at least as I characterized him so far. In that way perhaps Realism is superior, but then, it isn't clear that Realism is the best explanation period. Why Is Realism a better explanation of the two perceived cars than the evil demon hypothesis? Perhaps an evil demon brings these cars in and out of existence to trick you into thinking that Realism is true.

PA

Well, what's wrong with "we have a faculty which reliably produces a belief in Realism"? — Inter Alia

You have to say what the faculty is. And the difficulty is, the faculties typically accepted as possessed by humans by Realists don't fit the bill. Sense perception won't do it. Inference won't do it. So which faculty reliably produces belief in Realism?

We mistakenly think the bridge is there even though we can't see it. We mistakenly presume electricity is not in the 240volt wire because we can't see it. It's too easy to come up with thousands of these, I presume I'm missing something? — Inter Alia

I still don't grasp the volt case. If I believe that the volts exist unperceived I won't put my finger on an exposed live wire. As it happens - let's suppose - the volts only exist while perceived. Why should that make any difference to whether I hurt myself or not? My believing - mistakenly - that the volts exist unperceived keeps me perfectly safe because it stops me from putting my finger on a live wire, even though the belief is false. Why is that mysterious?

The bridge example is clearer but manageable. The Idealist holds that there is no bridge when unperceived. Suppose that's true and I walk over where I mistakenly believe there to be a bridge. What will happen is quite simple. I will perceive a floor underneath my feet, and that floor, since it is being perceived, exists. The floor which I feel under my feat is the bridge! Obviously a crude Idealist holds that if I weren't feeling the floor under my feet at that time, the bridge would not exist. But why does this create some mystery about why I don't hurt myself more? I could understand if the Idealist merely said that things don't exist when you aren't looking, since that would imply that if I walk where I believe there to be a bridge but have my eyes closed, I will fall to my death. But even the crudest Idealists will hold that the necessary condition for existence is being perceived, not merely seen.

The laptop thief - what I meant was someone could steal your laptop whilst you've got your eyes shut. You have to decide do I need to protect my property when I can't see it (because it's really there) or can I continue to have this lovely daydream with my eyes closed (because the laptop isn't really there whilst my eyes are closed and so no-one can steal it)

The approaching car - again not quite what I mean, I meant a car is definitely approaching, you establish that with your own eyes, but the (let's say due to panic, or flying debris) you go both blind and deaf. Is the car still coming? You've got no reason (apart from conservatism) to think it is, there's no longer any evidence of it, do you get out of the way?

The moral cases you seem to have some sympathy with anyway, I'm basically saying that most of life is like that. One moral or necessary decision after another.

Skepticism is only possible when one does not need to decide one way or the other, and in such cases it is basically redundant. — Inter Alia

I see, so it isn't Evidentialism as such that let's us down with decision making. Its Evidentialism plus the idea that we have no evidence that Idealism is false. Let's take the examples in turn again.

The Laptop Thief
There are two ways to interpret the scenario. First, it might be that I just have my eyes closed and can still hear the man stealing my laptop. I can hear him unplugging it, rustling the keys, mumbling about how heavy it is, stuffing it in his bag, and so on. In that case I do have reason to think that a man is stealing my laptop don't I? So Evidentialism will yield the satisfying result that we ought to believe the laptop is being stolen and so protect it.

Second, it might be that I cannot perceive my laptop being stolen at the present moment at all. Does that mean that we have no reason to believe that the laptop is being stolen? I can't see that it entails that. Perhaps I remember seeing the laptop being stolen just 1 second ago when I was perceiving it, and that's my evidence. Unless you think that remembering that the laptop was being stolen 1 second ago is not good evidence that it is being stolen now? By contrast Conservatism seems silly here. Perhaps I just believe, willy nilly, that my laptop is being stolen - I'm an incredibly anxious and suspicious person; the sort that constantly expects conspiracy. I haven't seen or heard anything which might suggest this. I am just such a serious conspiracy theorist that I believe it to be. Conservatism entails that the sensible thing for me to do is to continue to believe this and rush to my laptop in its defence. Now, in one sense, it is sensible for me to do that. Given that I believe the laptop is being stolen, it is sensible to rush to its defence. But my belief here is not sensible, since there is no evidence for it, and so my action is all things unconsidered not sensible either.

The Approaching Car

Much the same thing can be said here. Although I am no longer perceiving the car I can remember that it was approaching a moment ago, and I know that a car which was approaching a moment ago will likely still be approaching now. I think I know what you are getting at with these two cases, and that's that although my response here is fine, an Idealist cannot make it. He simply cannot say that the car is likely still approaching while unperceived because it was approaching a moment ago, since that refutes his thesis. Right, but the Idealist can simply say that an experienced car was approaching a moment ago, and he knows from past experience that if you perceive a car approaching at one moment and you do not move, you will, shortly after, experience a car hitting you. He need not postulate a car which exists unperceived; just a car which approaches and a car which hits him.

What it means for you to exist, what it means for you to experience, each of these concepts only has meaning in the context of a public world. — gurugeorge

What do you mean 'a public world'? What's a 'public world', and why does the concept 'experience' only have meaning 'in that context'?

Suppose you do restrict yourself to the consideration of present experience without presuppositions, then in that case the "you" that's experiencing isn't a human being with a body, it's something like Descartes' "thinking thing," or the "pure experiencing" of the non-dual mystic, and its object is something like a 3-d cinema show hanging in nothing. So in that scenario, concepts like me and experience, or sensation - their grammar, as ordinarily used, doesn't have any purchase. Those concepts are "built for" (have criteria in terms of) the physical world, and then only secondarily are introjected by the philosopher in course of the peculiar exercise of Cartesian bracketing; but they only have verifiability conditions in a physical world, they have no verifiability conditions in that queer, truncated realm. — gurugeorge

There is a lot here to discuss. The characterization '3-d cinema show hanging in nothing' is both uncharitable and difficult to understand. What is meant by 'hanging in nothing'. If you mean here that experience is the presentation of images which are pictures of the world, and the phrase 'hanging in nothing' is supposed to indicate that we are bracketing the issue of whether the pictures really are of the world, that is not at all what I meant to do. That obviously presupposes a veil of perception, which I reject. What I mean to restrict us to at the outset is simply what can be seen. Now, in one sense, when I look in front of me at the moment, what I can see is a laptop, and as you said, the laptop exists unperceived. But in another sense, that isn't what I see at all. What is available or given to my consciousness at this moment? Not the property of existing unperceived. Only certain patches of colour of a certain size and shape. Now, I am not saying that all I experience, in the ordinary sense of experience, is patches of colour. What I am saying is that that is the only part of my present experience which is indisputable; it is the only part of my experience for which there is a clear answer why I should believe it to be there. On the basis of this experience alone, there is no answer as to why I should believe that anything exists unperceived. You are right that this is a non-ordinary concept of experience. It is one tailored for the purpose of building an indisputable system of philosophy - not one which is certain, just one where there is a sensible answer as to why each part should be accepted. You don't even have to call this concept experience if you don't want. Call it schmexperience for all it matters. What I schmexperience is only certain colour patches of a certain size and shape. These things are given to me in such a way that it is simply indisputable that they are there. I cannot sensibly doubt that there are these patches of colour before me at this moment. There is an obvious reason why I should believe it. With that said, I am happy to concede that the ordinary concept of 'experience' cannot be meaningfully applied here.

So in essence what you are doing in the course of the Cartesian exercise is re-defining "experience" to mean something like, "a 3-d cinema show hanging in nothing," which is the newly discovered object of your ("you" now as a pure point of perception) exercise in Cartesian bracketing. — gurugeorge

As I said, the concept of 'experience' implicit in my remarks is the concept of 'what is indisputably before my consciousness'. I don't want to 're-define' anything. I am happy not to use the word 'experience' if it is so troubling, although to drop that word represents a departure from traditional ways of discussing the issue.

If you depart from the criteria for concepts as used in the ordinary sense, then you've lost the ability to apply those concepts in the presuppositionless stance too. But then what are you talking about after all? You don't know, you don't know what it is, you don't know the first thing about it. But if you don't know the first thing about it, how can you draw usable criteria from it? — gurugeorge

Does the concept which I have explicated above have no meaning? It seems to me that I understand it perfectly well. Perhaps you are worried because the concept is not 'ordinary', but I don't see any reason to think that if a concept is 'not ordinary' then it must be meaningless. What is so magical about 'ordinary concepts' that they get to have meaning but 'non-ordinary' concepts don't.

Bracketing presuppositions is an important tool of philosophy, for sure, but bracketing all presuppositions is not definitive of philosophical reflection, and actually doesn't lead anywhere, can't lead anywhere. It's a Chinese finger puzzle for the mind (or Wittgenstein's "fly bottle"). — gurugeorge

This is just the suggestion that it is impossible to build an indisputable system of philosophy, which is just what ancient scepticism was. I've always thought that Wittgenstein was a Pyrrhonian.

Yes. It's a non-problem, because the Realist and the Phenomenalist take in each others' washing. Each actually allows some grain of truth in the other's position. The grain of truth that the Realist has to accept from the Phenomenalist is something we already know and are familiar with - that perception can't be "direct" in the Naive Realist sense (although that doesn't mean it can't be direct in other senses - the actual directness is in the fact that there are no such things as mistakes in a casual chain from object to brain). — gurugeorge

I know some Realists and Phenomenalists made a lot of this issue of the 'directness' of perception. Russell did, for example. I don't think that's important at all. All that matters is that certain elements of experience are unproblematically available to consciousness in such a way as to make them indisputable, and some aren't. The property of unperceived existence, isn't. It is painfully easy to produce a story, compatible with all of the indisputable 'given' elements of experience such that nothing exists unperceived. I have no way to prove to you, I suppose that the property of unperceived existence isn't given to my conscious awareness like the property of blueness is. I take this to be patently obvious to anyone who has the faculty of sense perception.

But then if it's not sensation, if it's being thought of truly "without presuppositions," as the 3-d cinema show hovering in nothing, then no conclusion can be drawn from its existence or form whatsoever. It's already a foregone conclusion that it's not going to be able to connect to anything external to it, it's not an interesting discovery that it can't connect to anything external to it. — gurugeorge

I don't think its foregone at all. Why is it so obvious that no conclusion can be drawn from the given? I certainly can't tell, a priori, that this is so. The discovery, if it were one, would be that almost nothing that I believe is indisputable, and that sounds to me like an interesting philosophical discovery. I can't stop global warming with it, but all the same.

As I said, no one's claiming that physical cameras and laptops are such things as exist necessarily and couldn't possibly not exist, like God is supposed to be. — gurugeorge

I didn't use the concept of necessary existence in my reducio about God. I used the concept of existence, and you did claim that laptops are such things as exist - which was the premise of the reducio. So it still seems to me that that argument is parallel to the one which you gave.

I find the critics of the Cartesian approach pretty convincing. — ff0

What is it about the Cartesian approach that you find untenable?

The theoretical epistemology-obsessed approach has nothing to do with this kind of living. — ff0

I agree.

We 'know' that we are in a shared situation or world in a pre-rational way. — ff0

If 'know' means that the thing known is indisputable, it isn't clear to me that that is true. By 'Indisputable', I don't mean 'certain', I just mean that there is some reason, no matter how meagre, which sensibly answers the question of why we should believe it to be true.

One doesn't specify the nature of the thing one is perceiving from the qualities of present sensation, as you keep wanting to do; one specifies a logically possible object apriori and one tests whether the thing one is perceiving answers to those properties, has that identity. — gurugeorge

Suppose I do that. Suppose I specify apriori that I want to figure out whether there exists anything which is black, rectangular, has a motherboard and exists even when unperceived- in a word, a laptop. I then look to my perceptions. I perceive that the thing is black and rectangular. I look inside and perceive that it has a motherboard. But I don't perceive that it exists unperceived. I can't. So I find this thing, a camera, and I take a photo with my eyes closed and get a print out. The picture is a picture which looks just like the thing I was earlier looking at. What does this show? That the laptop existed unperceived while I took the picture? Well if the thing I used really was a camera then yes, it shows that. But unless I already believe that things exist unperceived I won't believe that it really was a camera - that is, I won't believe that the picture it took is one of a thing which existed unperceived. And this you already admitted.

But now you add something more:

But that's a process that takes place in a world that's already accepted as public, already acceptd as physical, already accepted as taking place in time and space, and often involves instruments and other people, it's not a sheer beholding of present sensation. — gurugeorge

So, I already have to accept that things exist unperceived before I can use the camera test. Got that. And then:

But it's from that world that the very concept of "exists unperceived" (and the standards for resolving it) comes; philosophers aren't originating that concept, as if it were some kind of special armchair discovery, they're merely pinching it, detaching it from its normal moorings and making an odd game out of it. — gurugeorge

I am not sure about that first part. I'm not even sure what is meant by saying that the concept of unperceived existence 'comes from the world of public physical objects'. What do you mean 'comes from'? Are you saying that I couldn't possibly have that concept unless there were physical objects? Surely I could gain the concept of unperceived existence just by reflection on myself and my experience. The concept of existence I can derive from knowledge of my own existence. The concept of experience I can derive from awareness of my own experience. I can negate the concept of experience to create 'unexperienced' and then put the two ideas together to create 'unperceived existence', and then it is just a matter of imagining a thing which has that property. Why does the concept need to 'come from' the world of physical objects, whatever 'comes from' means here?

I agree that the camera test standard is the ordinary standard for testing whether something exists unperceived, by why can't we question whether that standard is really sufficient? The standard itself presupposes that things exist unperceived and so it is quite a lousy standard if it is intended to establish for the first time that anything exists unperceived, though admittedly it is a good standard once we have accepted that certain things do exist unperceived.

Thus, I don't think philosophers are stealing anything. You can get the concept of unperceived existence in the armchair. I don't know what is meant by 'the concept comes from the public world of physical objects'. The concept comes, like every concept, from experience, and from experience which I can be acquainted with in the armchair.

Incidentally, I thought originally that you were defending Realism. But now it turns out that you think Realism is just as non-sensical as Phenomenalism. Is that right?

At any rate, I think you will agree that a proof of the existence of God which only works if we assume that God exists is absolutely worthless if we are trying to establish God's existence for the first time, without merely assuming it to be true. I think you will agree that it is of no consolation whatsoever to be told that the concept of 'God's existence' is a concept which 'comes from the world in which God exists' and to do anything like question that idea is to take the concept 'God's existence' and make an odd game of it. Is there some difference between your argument and this one? What is it?

PA

People have been doing so, though just not by name. gurugeorge's argument about the camera is the corroboration argument, no matter what device we use recording whatever phenomenon (light, sound, radiowaves, time, sonar, radioactive decay) they will all record the laptop as existing when our eyes are shut. They can all be explained away, it's just an argument after all, not proof, but that's basically it. — Inter Alia

But I did discuss this argument with gurugeorge, over many posts. My basic point has been that the argument is circular, since it assumes, without any reason at all, that the recording on the device is a recording of something which existed when not perceived, and no one who doesn't accept Realism will accept this understanding of the device. Now I don't deny that its not meant to be a proof, but is an argument of a more modest kind. But my point is that even as a modest argument trying to show that things probably exist unperceived it fails, because it is fallacious, circular, begs the question, however you want to put it.

Putman's 'no miracles' argument is basically what I've been saying about harm. If Realism was wrong, gave us the wrong impression of something about the 'real' world, it's pretty remarkable that no-one has yet come to any harm as a result. If we've all been presuming the laptop is there when we shut our eyes and actually it isn't, it's quite astounding that this error has has no effect on us whatsoever despite being perpetrated in every single interaction of every person in the world thousands of time a day. Putnam goes on to defend scientific realism in the same way with the simple incredulity that our scientific prediction could be so reliable if the world was not as they presumed it to be — Inter Alia

I'm a fan of Putnam, but I am not sure what harm would result if we made this error. I mean, on Idealism, things exist if and only if they are perceived. Suppose the world were like that and we mistakenly thought things existed even unperceived. What harm might that cause? Could you give an example?

Again, not foolproof, but certainly as much a contender for reliable source as Plantagina is for Theism. — Inter Alia

Plantinga is not supposed to be the reliable source. He says we have a cognitive faculty which reliably produces the belief that God exists. If that were true, we could reliably establish God's existence by use of that faculty. Now, it might not be true, and one might be inclined to doubt it. But my point is that all I wanted from the Realist was some story like this; a story which entails that we can reliably establish that Realism is true by some means, even if people who don't accept Realism are inclined to doubt that we have this faculty. (Note that this is different from the Corroboration Argument, since that is supposed to be a way of inferring that Realism is true from premises using only cogent forms of inference. Circular reasoning, not only fails to convince people who don't accept the conclusion, but is also fallacious, not cogent).

Yes, that's exactly it. Sometimes you have to decide something, contraception, abortion, faith schools, segregation halal meat, the approaching car, catching a ball, the laptop thief, we have to decide one way or another. If Evidentialism isn't going to help, what is? — Inter Alia

It is easier to discuss particular examples. Take the laptop thief. Evidentialism says that unless you have some reliable way of establishing who the laptop thief is, you ought not believe that it is Inter Alia. And this seems to me to make perfect sense. I shouldn't just go accusing you of stealing a laptop without a shred of evidence.

Now take an approaching car. Evidentialism says that unless you have some reliable way of establishing that a car is approaching, you ought not believe that one is. And this seems to me to make perfect sense. What kind of maniac would I be if I just believed, out of the blue, that a car was approaching and dived, screaming and crying, onto the nearest sidewalk. I had never heard the sound of a car or seen one. I just decided one was coming. That would surely be foolish.

Now take abortion. Evidentialism says that unless you have some reliable way of establishing that abortion is right or wrong in this particular case, you should not believe that it is or that it isn't. Moral cases I think are difficult for Evidentialism, since evidently some decision has to be made about whether to abort of not. A non decision is effectively a decision not to abort, and so one has no choice but to make decisions of this kind. I think what the Evidentialist should say is that, insofar as it is possible not to make a decision, one should only make a decision if there is some reliable means of establishing what the right decision is.

Why not see what Conservatism has to say about these cases? Conservatism says about the laptop thief that if I already suspect that Inter Alia stole my laptop, I should believe this unless I have some reason to think otherwise. That sounds quite unfair to you. Conservatism says that if I already believe that a car is approaching, I should continue to believe that one is unless I have some reason to think that it isn't. Never mind that I never heard or saw a car. I just believe this because I have an irrational fear of being run over every time I go near the road. Conservatism says that this belief, produced by my irrational fear, is what I should believe. Conservatism says about abortion that if I already believe that abortion is right in this case, even if I have no means whatsoever of reliably figuring out whether it is or not, I should believe that it is right and do the abortion, unless I find some reason to think it is wrong. That sounds like a dangerous idea to my mind. I have no reliable means at all of figuring out what the right thing to do is, but I still go ahead and terminate a potential human being because I believe, for no particular reason, that abortion is right in this case.

No doubt I have offered a straw man of Conservatism. If I have done so, I have done so with tongue in cheek, to provoke you to defend Conservatism with the rigour I am sure you are capable of.

PA

I understand your preference for Evidentialism, I just don't see how it applies here. Neither Idealism nor Realism have any more reliable source for the belief than the other. The same is true of Theism and Solopsism, they're all just ways of thinking about the world that only make sense if you accept their axioms. You've cited Plantagina, as your example source for Theism, but have ignored Putnam's 'no miracles' argument for Realism. You've cited Plato, but ignored the Corroboration Argument. There are plenty of sources for the belief in Realism as there are for most other metaphysical views, but each has its counterargument, that's why Evidentialism let's us down. — Inter Alia

I am not defending Idealism as true. I am happy to concede that there is no more a reliable source for Idealism than we seem to have found for Realism.

I did cite Plantinga, but not as a 'source for Theism', if this means that I think Plantinga has an argument for Theism. He doesn't. He just tells a story which, if true, gives us a reliable source for belief in God. I only cited it as an example of the kind of thing which I wanted for Realism: a story which, if true, gives us a reliable source for belief in Realism.

I haven't ignored Putnam's no miracles argument for Realism, nor the Corroboration Argument. I just haven't discussed them because nobody here mentioned them until now, and no one has sketched them as a defence of Realism in this thread. I was just discussing the themes that came up. I'd be happy to discuss them if someone wants to sketch their interpretation of them as a starting point.

I tend to apply Evidentialism in every area. If we can't find reasons, even in the very weak sense of a plausibly reliable source, then I hold that we ought not to believe. I am not sure what you mean by 'Evidentialism let's us down'. How does it do that? Just because it doesn't tell us what to believe when there are both arguments and counter arguments?

I'm not saying that. I am saying that you are saying that about their attitude to skepticism, which is about enquiry or it is about nothing.
What seems to be happening is that Pyrrhonianism is declaring enquiry useless. That is a political position, and one that few who had not given up on could ever aspire to. I assume they are supposed to reject all reason and enquiry and substitute Faith? — charleton

No they don't substitute faith or reject all enquiry. In fact, they often contrast themselves with dogmatists. Dogmatists think that enquiry can be settled once and for all about some matters. Pyrrhonians just keep on enquiring. It isn't that enquiry is useless for the Pyrrhonians. Its just that it has severe limitations which force them to suspend judgement about the real nature of things and 'go along with' the customs and habits of the day, making no claim that those things are true. I have always found the view paradoxical, but it is what they held and even practiced. Some of the ancient Pyrrhonians were early doctors.

PA

You agree with me that nobody who doesn't already accept that Realism is true would accept your argument about cameras. So someone who has no belief about whether anything exists unperceived or not would not be (sensibly) convinced by your argument about cameras. If that is so, what is the point of your argument about cameras? What use is an argument which can only convince people who already believe the conclusion? I have some of your quotes here for ease of exposition:

Quote 1

Yeah, but there's nobody who actually believes that. People who say they don't believe in Realism don't really disbelieve Realism, they just disbelieve Realism in toy examples where they're hypnotizing themselves into artificially shrinking their experience of the world down to the experience of sensory qualities in abstraction. It's a rakish pose. — gurugeorge

Quote 2

I understand what you're saying: the camera is on a level with the laptop, and if the laptop's unperceived existence is dubious, so is the camera's, so one can't be used to prove the other. But neither the laptop nor the camera's unperceived existence is at all dubious - if they're truly laptops and cameras. — gurugeorge

Quote 3

Similarly, this tangle you're getting yourself into is the result of you abstracting away what you know of the thing you're experiencing, so that "literally" to you really means a detached, truncated description of some sensory experiences in abstraction. — gurugeorge

Quote 4

In these examples, the properties (respectively, having a motherboard and CPU, existing unperceived) aren't being directly perceived in sensory experience, nor are they inferred from sensory experience, they're inferred from the things' being what they are, supposing that they truly are those things. — gurugeorge

Quote 5

you are after all painting yourself into the corner of a phenomenalist/idealist stance. — gurugeorge

Quote 6

You have to accept this, unless you're going the phenomenalist/idealist route you deny. It's completely incoherent to say, "This is a physical object, but I can't be sure, from inspection, whether it exists unperceived." — gurugeorge

Quote7

Present inspection isn't the sort of thing you could logically expect to reveal that particular property. What you could logically expect to reveal that property would be things like the camera test. — gurugeorge

Let us begin by distinguishing between perceiving something and perceiving that something is the case. I say that, though you might perceive a laptop - where this is by definition something which exists unperceived - you can never perceive that it is a laptop, since the property of unperceived existence is not something which you can possibly perceive. You agree with this in Quote 4 and Quote 7. But you worry in Quote 3, Quote 5 and Quote 6 that my characterization of sense experience is already committed to Phenomenalism or even that it is incoherent. It isn't. All I am saying is you never perceive that something exists unperceived, since that property is not one which you could perceive. Similarly, I say that if 'laptop' means partly 'a thing which exists unperceived', you can never perceive that something is a laptop, even though you might be perceiving a laptop. Perhaps I did not make this clear before.

I say that if you cannot perceive that something exists unperceived then, if you are to have any reliable means of establishing it, you need to infer it from the properties that you can perceive (perceive that). This was what I thought you were offering by offering the camera test. I thought you were trying to give an inferential argument that things exist unperceived. Understood that way, the camera test is fallacious. Nobody who did not already accept Realism would accept the ordinary understanding of what the camera can do, even if it is part of the concept 'camera', and that ordinary understanding of what the camera can do is just presupposed by your camera test. You admit this of your camera test in Quote 2, but insist that there is no problem here, because 'neither the laptop nor the camera's unperceived existence is at all dubious - if they're truly laptops and cameras'. I struggle to understand why you have said this. If we are genuinely open about whether Realism or Phenomenalism is true, you have admitted that the camera test won't sensibly convince us of Realism. What use is an argument which can only convince someone who already believes the conclusion? I think such an argument is worthless, which is why I called it fallacious, and using arguments of that sort is not at all truth conductive.

Inferring that the thing which I perceive exists unperceived from the premise that what I perceive is a camera and cameras, by definition, exist unperceived is just as fallacious as arguing that the thing which I mystically perceived must exist because what I mystically perceived was God and God exists by definition. Nobody who doesn't accept the conclusion will accept the premises.

You try to anticipate my reaction to your post here:

Now, you might say something like this:- "Ha! You think you are perceiving physical objects, but for all you know you might be perceiving something that to all appearances look and behave like physical objects, but lack the property of existing unperceived."

In that case we'd do the camera test. If the camera showed nothing there when I took the picture, that would be a verified example of something blinking out of existence when unpercieved. BUT THEN IT WOULDN'T BE A PHYSICAL OBJECT AS WE UNDERSTAND PHYSICAL OBJECTS It would be something new, something mysterious and interesting, that shares some properties with physical objects, but lacks the property physical objects have, of existing unperceived. — gurugeorge

You are right. I would say that, and you would offer me the camera test, to which I would answer: "the camera test could not convince anybody who doesn't already accept Realism. It couldn't convince someone who is open to both Realism or Phenomenalism. So what is the point of the camera test? That it could convince you? But you already believe that things exist unperceived without doing the test!"

So far we have seen that neither sense perception nor inference is a reliable means of establishing that things exist unperceived. You agree that we can never see that something exists unperceived. I am not sure whether you agree that we cannot cogently infer it, but we have seen that if your camera test is supposed to be such an inference, it is fallacious because it presupposes Realism and arguments which assume what they set out to prove are not only incapable of convincing someone who does not believe the conclusion, but are also completely unreliable forms of inference. So if we can't reliably reach the belief that things exist unperceived by sense perception or by inference, how can we do it?

But then, perhaps you weren't offering the camera test as a kind of inference. Perhaps you were saying that the camera test is a reliable method of establishing that things exist unperceived, distinct from sense perception and inference. If that were your suggestion, you would be doing just what I asked various others to do: locate a reliable source for the belief that things exist unperceived even if there is no way to prove that the source is reliable to anyone who didn't believe that it was. That would certainly make a lot of sense of your insistence that 'if the camera is a camera, then it can verify that things exist unperceived'. Before I discuss this suggestion. Is this what you meant to do? If it is, I apologize for having missed it for so long.


, thanks for the clarification.

Sorry, I mean the following;
1. We enter adult life as Realists for whatever reason (evolution or indoctrination). My test with the laptop the if proves this.
2. We have been given no good reason to replace this belief with any other, at the very least they are all equally good, but none is arguably better.

Therefore, logically we should continue with this belief until a better one is presented to us. — Inter Alia

Your argument assumes:

Conservatism. We ought to continue to hold the beliefs we do hold, unless we are given some good reason to replace them.

I can see the merits of Conservatism. It certainly saves time and effort having to constantly worry, in Cartesian fashion, whether what we believe is actually true and whether we can find any reasons for it. It is also much more useful insofar as we can simply build on the beliefs we already have, and that can bear practical fruit.

I have to say that I'm not of that philosophical inclination. I incline towards the 'evidentialist' tradition:

Evidentialism. We ought only accept those beliefs which we can find some reason to think true.

I am happy to construe Evidentialism weakly, so that if a source of belief is in fact reliable, that source can give a good reason for holding the belief, even if there is no way to prove that the source is reliable to anyone who didn't believe that it was. I don't think I have any way to convince you of Evidentialism over Conservatism. I suppose that all I could say is that Evidentialism is a safeguard against wild, unreliable speculation. It consoles us to stick to what we at least have some reliable means of establishing. Conservatism, in contrast, strikes me as an unreliable preference for the dogmas of the day. But I know you will reject this characterization.

PA

I agree that its not the most common use these days, even in academic philosophy. Though if you gloss the Pyrrhonian school as having 'given up' and as full of 'angst' and 'apathy', I can only assume you haven't read the Outlines or any scholarly work on the school, because they had an entirely different attitude from that.

Your view is angst followed by apathy. — charleton

First, it isn't my 'view'. It isn't even how I use the word 'scepticism' most of the time. The definition to which you are referring is the one which the ancient sceptics used. The ancient sceptics of the Pyrrhonian school practiced suspension of judgement about every matter and claimed that this lead to peace of mind. Here is Sextus, our best source on ancient scepticism:

"Scepticism is an ability to place in antithesis, in any manner whatever, appearances and judgements, and thus -- because of the equality of force in the objects and arguments proposed -- to come first of all to a suspension of judgement and then to mental tranquillity.". -- Sextus Empiricus, Outlines of Pyrrhonism.

Note, he is talking about what 'scepticism' meant to the ancient Pyrrhonain school. Since this is so, your whole claim about how the definition 'flies against' what is ordinarily meant to the point of an abuse of language is just irrelevant. Obviously people today use the word 'scepticism' in a different way to the way it was used roughly 2500 years ago. So what? What I was saying is that the ancients used the word (or their ancient equivalent which is translated 'scepticism') that way.

Right. But my point is that this way of talking about things ('exists unperceived') is (to my mind) something like an artificial game that rests on 'pragmatic' foundations. Why not doubt this theoretical framework itself? What is this framework parasitic upon? Do you assume some kind of Newtonian space? With time as a separate dimension running continuously? What does it mean that something is there, apart from all human purpose? Is it some kind of 'matter' that just endures there in 3-space? And maybe it blinks out when we turn our eyes away? But this assumes the correctness, meaningfulness, and stability of this 3-space and a certain mathematical notion of time.

In a way I'm being skeptical myself here, but about the framework rather than about the objects. I'm skeptical about the usual version of the epistemological game. For me it's as artificial as chess. What's wrong with being artificial? Nothing, really. But I have 'aesthetic' reasons for wanting to get closer to the lived situation, which you may or may not share. I want to be 'objective' in a non-theoretical sense, which is to say that I want theory to be closer to non-philosophical life. — ff0

I don't understand what you mean when you say that the whole thing is 'artificial'. All of us have a clear idea of what it is for something to exist, since, as Descartes pointed out, one has a first hand awareness of one's own existence. Moving on to what it would be for something to exist while perceived by me. The thing which I am looking at right now, for example, exists and I think this is perfectly intelligible, even if I couldn't define 'exists' in terms of anything more basic, except perhaps by saying 'there is something'. If I understand what it is for something to exist while perceived by me, and surely I understand what it is for me not to be perceiving something, it is quite a simple process to arrive at the concept of 'unperceived existence', again even if I couldn't define it in more basic terms, except by saying that 'the thing which I saw a minute ago is still there even though I am no longer perceiving it'.

I find the notions of 'matter' and '3-space' far more difficult than the notions 'existence' and 'perception', since I have an immediate awareness of both my own existence and my ability to perceive, whilst 'matter' and Newtonian '3-Space' are (perhaps correctly) postulated to explain my existence and the things I perceive.

You say that this whole language of 'existence' and 'perception' is artificial, but I don't think it is at all. I'm immediately aware both of my existence and my perceiving, so in what sense is it artificial? Without an answer to that, I can't see what you mean in saying that you desire theory closer to 'non-philosophical life', since it seems to me that the concepts 'existence' and 'perception' can be understood merely by reflection on your own mental life and so they are, as it were, as close to your life as could be!

Quite right. The justification for the assumptions built into the model is the empirical adequacy of the model as a whole. This is a pragmatic rather than a foundationalist approach to justification. Remember, we're just looking for "good reasons", not "deductive proof". — Aaron R

If by 'pragmatic justification' you mean 'its useful to believe it', then that is not the sort of things which we began by looking for. But the argument which you suggest is fortunately not of that kind at all:

For instance, classical models predict that if the planet Jupiter ceased to exist every time that no one was looking at it, then the earth would be displaced from its current orbit with catastrophic consequences for its inhabitants. This obviously doesn't happen. — Aaron R

I think this is a promising argument, perhaps the most promising so far. But there may be some difficulties. The classic model clearly does predict that there will be observable consequences if certain things don't exist while unperceived, but I have two queries and I can only begin to answer one of them. Perhaps you can help further.

First, whilst it is clear that, according to the classic model, an object like Jupiter not existing while unperceived would produce observable consequences, it is less clear that all objects would have such consequences. What about my laptop, for example. I can't think of any observable consequences which could reasonably be expected if it didn't exist while unperceived, certainly not according to the sort of physical theory which predicts the same about Jupiter. And so an issue still remains. While we have a reason to think that Jupiter exists unperceived, there doesn't seem to be one for thinking that the objects closer to home exist unperceived.

What do you think of the following extension of your argument? If we have a reason for thinking that Jupiter and all the other planets exist unperceived, then it would certainly be very strange if more homely objects don't. We would then be in a universe in which some of the largest objects in it exist unperceived but certain objects don't. Certain objects just pop in and out of existence when they are perceived and certain ones are permenant, and there is apparently no good explanation of why this is so. That certainly is a very odd world, and it would be far simpler to suppose that everything in the universe has the same ontological status unless there is some reason to think otherwise. Thus, since there is no apparent difference between my laptop and Jupiter which would explain why they are ontologically different, the simplest explanation is that my laptop also exists unperceived.

This brings us to the second difficulty. The classic model is what gives us a reason to believe that Jupiter exists unperceived. What is the evidence for the classic model? If that evidence ever assumes that anything exists unperceived, the argument will be circular and so fallacious. I suspect, sadly, that the classic model and the evidence for it do presuppose that things exist unperceived. But I do hope I am wrong about that!

I think its clear enough that your use of the word is idiosyncratic, and atypical. — charleton

I am using the word the way it is used in contemporary academic philosophy. I reject the doctrine that there is a 'typical' meaning of the word 'scepticism' outside of philosophy. Indeed I reject the doctrine that there is a 'typical' meaning of most interesting words.

Simple, such a belief has been entirely harmless for the (more than I'd care to mention) years of my life so far. Can anyone say the same of Idealism? — Inter Alia

Well many people have been Idealists and lived perfectly decent lives. So it isn't clear to me that Realism has an advantage in that department, but I suspect that that is a person relative issue.

You have asked me to address you argument, but I'm not sure exactly which argument you mean. I'm going to take a guess:

When we see the bent stick, or any other illusion we recognise that we can't trust our initial sense data, but where do we look for an alternative explanation? Do we leap to the conclusion that it must be magic because we're standing in a fairy grove? No, we look back to other, more complicated sense data from experiments with light, we see how this thing we sense as light gets refracted and we presume that's what's happened to the stick, not because it's infallibly right but because we have no better explanation than the one we somehow seem to have entered adulthood with. — Inter Alia

We look at the stick out of water and we perceive a straight stick. Submerge the stick and perceive a bent stick. What we have now are two bits of data: The stick is seen to be bent in one circumstance and seen to be straight in another circumstance. Some how we have arrived at the belief that the straight stick exists while unperceived and the bent stick doesn't - there really is no bent stick, its just an illusion created by the refraction of light. I think its relatively clear to me how we reach the conclusion that the bent stick doesn't exist when unperceived, and you have detailed that well in this quote. But far less clear is why we believe that the straight stick exists when unperceived. It might be that there is 'no better explanation than the one we somehow seem to have entered adulthood with', but if so, why is it the best explanation? Why is it not an equally good explanation to suppose that the straight stick doesn't exist unperceived either? I'm not asking for some infallible guarantee that the stick exists unperceived, but just for any account of why this is a better explanation than the hypothesis that it doesn't exist unperceived? What makes you postulate an unperceived straight stick?

no one has yet provided any evidence that materialism causes any harm or can be proven logically impossible. Those two things make it an equally valid choice of world view in my opinion. — Inter Alia

Excuse me for butting in, but are those really sufficient conditions for a viable choice of worldview? I wonder if this is a little weak. All sorts of speculation is harmless and not demonstrated logically impossible. The Greek pantheon is harmless and not demonstrated logically impossible, as is Leibniz's Monadology, The old Stoic dual aspect theory of nature, The NeoPlatonic doctrine of emanation from God, a Dualistic Christianity - in fact, Creationism seems both harmless and not proven logically impossible. But then, it depends what counts as harmful and what doesn't. Is it harmful if a doctrine contradicts the science of the day? Or is something only harmful if it causes actual physical or emotional harm to people?

PA

I think we have reached an impasse. From where you see it, my characterization of the issue is just an odd way of talking which creates problems. For me, you are just insisting that things exist unperceived by definition. I will try once more to try to make you see it my way.

Look at your computer. What do you see, literally? Describe every property of the thing you are looking at, without adding any property which you can't see. You might say things like 'a black, rectangular, three dimensional thing with letters on it'. No matter how careful and detailed is your description, you will never say 'which exists when I am not perceiving it'. If you did say this, you would no longer be describing, literally, what you can see. You would just be adding a property which you believe the object to have, but which you can't see that it is, rather like the amateur artist who draws the human eye as a perfect oval, because that's the shape he believes it has (artists have to work quite hard to learn only to draw what they see and nothing more).

If you have never seen the property of unperceived existence, how do you know the object you are looking at has this property? Can you infer that property from what you do see? If you can't, then how can you possibly know it? 'Know' is being used here merely in the weak sense of reliably produced true belief. How can you reliably believe it?

You have said that if you take a picture with a camera then that will prove that things exist unperceived. But how? Since you cannot literally see that things exist unperceived, I took it that you meant to offer an argument for it here, but I think that argument is fallacious. Here is something we ordinarily believe about cameras: you can put a camera up in a room when no one is in it and the camera can get you a picture of the things which exist in that room when no one is there. Equally, you could close your eyes and take a picture of your computer, and the camera would show you what the computer was doing when you weren't looking.

I think once I lay out this ordinary understanding of a camera in this way, you can see immediately that nobody who wasn't already convinced of Realism would accept without further question that any of it is true. Someone who does not believe Realism to be true would not accept that you can put a camera up and leave it to take a picture of what exists unperceived. Equally, if I do not accept Realism already, I will not just swallow the claim that the picture which I get when I close my eyes and press the camera button is one which is of a thing which existed when I wasn't looking. That is why it begs the question to assume that my pressing the camera button has this effect. Assuming it has this effect is assuming Realism and no one who doesn't already believe Realism will swallow that without question. Yes, it is our ordinary understanding of cameras and it might (though I doubt it) be part of the very concept of 'camera'. None of that changes the fact that no one except someone already committed to Realism will simply accept that ordinary understanding.

It comes down to this: what reason do you have to suspect that things could possibly exist that to all appearances seem like normal physical things, except that they pop out of existence when they're not being perceived? — gurugeorge

'To all appearances seem like normal physical things' is tantamount to 'to all appearances seem like things which exist unperceived', but as I have pointed out, you never see that something exists unperceived and so, literally, it never seems that way. Perhaps you can infer that things exist unperceived from something which we do see, but the insistence that what we mean by 'camera' is 'something which takes pictures of things that exist unperceived' and the insistence that we dare not speak otherwise is not going to do the trick. Nor is the, repeated, accusation that I conflate the object of experience with the experience. If by 'object of experience' you mean 'something which exists unperceived', then I am questioning whether there is any such thing as that. But to merely question it isn't to confuse it with the experience itself.

But, being the default position is not really a very good reason to keep thinking something, in fact it's a rubbish reason unless there is no better alternative, in which case it becomes an excellent reason for continuing to believe something. — Inter Alia

It is good that we agree that 'being the default' is not really a good reason for a belief. Let me ask, what is the advantage of believing Realism as opposed to Idealism? Is it a practical advantage?

PA

But do you have a better one? — Inter Alia

Is this strictly relevant? We began looking for a reliable source for the belief that things exist unperceived. You suggest instinct and I replied by saying that pure instinct is unreliable. You now ask me whether I have a more reliable method than instinct to suggest. I admit that I don't, but that is just to admit that there is no reliable source for this belief at all. Its just a wild speculation.

Imagine that we began by looking for a reliable source for the belief that ghosts exist. You suggest instinct and I say that instinct isn't reliable. You then counter 'ah, but do you have a better method for establishing that ghosts exist?'. No, I don't but that's no defence of the belief that ghosts exist. It is still wild speculation.

But why is the bent stick the illusion and the unbent stick the reality? I suggest because the unbent stick is what figures in the total practical context. Optical illusions are illusions, it seems to me, because they aren't something we can generally build on. We are future oriented beings. We make plans. It's in terms of these plans that we care about seeing a situation 'accurately' (usefully, enjoyably). If we weren't future-oriented beings who work and suffer now to avoid more work and more suffering later, we might not bother with doubt. In my view, recalling that care and projects are at the center of human life clarifies epistemological issues. — ff0

Well, if I were to say that some experience is an 'illusion', I wouldn't mean that the experience 'isn't one that I can build on'. What I would mean is that the thing which I experience does not exist unperceived. If I say that the bent stick I perceive is an illusion, what I mean is that the bent stick doesn't exist unperceived. And to add to this that 'what really exists is an unbent stick', is to add that an unbent stick exists unperceived. That's what I would mean by those words, at any rate. I certainly wouldn't mean anything merely pragmatic.

PA

, every instinct in your body would be crying out to tell you that £300 of equipment is about to be nicked. — Inter Alia

Are my instincts a reliable guide to reality? It doesn't seem so. When I look at the stick immersed in water my instincts urge me to believe that it is bent, before I learn that it isn't. It isn't clear that what I instinctively believe is reliable at all, and hence, not clear that this 'evidence' is really any good. At any rate, there are two senses of instinct. In one sense, a belief is instinctive just if it is 'hardwired' in. As I have said before, I highly doubt that Realism is hardwired, and suspect it is just implied by things we are taught as children and so we swallow it unconsciously. In another sense, a belief is instinctive just in case I cannot help believe it at this particular time. When you say 'every instinct in my body would be crying out', it seems that 'instinct' is taken in the second sense, and if so, I am quite confident that this is a wholly unreliable means of belief formation. Believing what I cannot help believe at a given time is an easy way to get taken in by dogma, persuasion, propaganda and merely popular ideas.

PA

"I perceive something" still presupposes realism (that the something exists). "I experience an internal sensation, one I've come to associate with perceiving something" is a description that does not assume Realism. It is obvious then that whilst you're not looking, that experience goes away, it comes back when you start looking again. This does not tell us anything about the laptop whilst you weren't looking, but it doesn't tell us anything about the laptop whilst you were looking either. Unless we relate the experience to the existence of an object outside of our minds the issue with closing your eyes and opening them again is an unnecessary distraction. The question is simply, does the experience relate to a thing outside of your mind? — Inter Alia

Hold your hand up and look at it. You are perceiving something at that moment. There are certain qualitative features or properties of which you are aware. This doesn't entail that those features or properties exist unperceived. It only entails that they exist right now, as you are perceiving them. Hence, I don't see how what I said presupposes Realism, so long as understood carefully. However, the phrase 'I experience an internal sensation' puts the sensation in as the object of the perception (the sensation is what I perceive, and that idea presupposes the veil of perception - that I can only perceive my sensation of a hand and never a 'hand'. This doctrine confuses the object of experience with the experience itself. That's a confusion which gurugeorge has been accusing me of and which I've been trying to avoid.

PA

I'd be interested to get your thoughts on what constitutes a "good reason" for believing that objects continue to exist when they are not perceived. You mention observation and inference, so let's head down that path a bit.

Consider classical physics. It is it reasonable to claim that classical physics is the best available model for understanding the motion of inanimate, macroscopic objects? Classical theories assume continuous trajectories and temporally persistent masses. They predict that if objects disappeared when unobserved then there would be observable consequences that we simply do not experience. A reasonable explanation, given the assumptions built into our best model, is that those objects don't disappear when unobserved, but continue to exist much as they were when last observed.

Is this philosophically air-tight? No. Is it reasonable and responsible for the purposes of belief? No question — Aaron R

A good reason to believe it would be any means of reliably establishing it to be true. Sense perception and inference I discussed because these are our most obvious and relevant reliable faculties.

It is true that classical physical theories assume that things exist unperceived, but this is hardly a justification of that claim. What reason do these classical theories give for supposing that things do exist unperceived? They certainly say it, but why do they say it? The theories predict that 'if objects disappeared when unobserved then there would be observable consequences'. What would those consequences be? It seems like the hypothesis that things only exist when perceived has all of the same predictive consequences as the hypothesis that they exist also unperceived. Perhaps I have missed something. But if so, it would be good to be clear about what.

I already told you: do something like take a picture while you have your eyes closed, and you will be able to verify that the object of your experience exists unperceived. Or just ask someone else. It's not that complicated or difficult, and there's no great mystery about it. — gurugeorge

But I don't believe you did 'already tell me'. This argument about taking a picture is a new argument introduced with this post, is it not? At any rate, this isn't all that clear. What exactly does taking the picture prove? So at this moment, T1, I am perceiving something. I close my eyes at T2. Does that which I perceived when my eyes were open still exist when unperceived? I take a picture with my eyes closed at T3. When I open them at T4, I can see on the camera a picture which 'looks just like' that which I experienced with my eyes open. What is the evidence we have at this stage? Well I remember perceiving something at T1 and I remember taking a picture at T3, and I am currently perceiving something else (namely, the picture which looks like what I perceived at T1, on a camera screen) at T4. These three bits of evidence don't logically entail that something existed unperceived and which the camera took a picture of.

I know at this point you will likely complain that they do entail it, because cameras take pictures of things and they can't take pictures of things which don't exist. So if I really did take a picture of something at T3, it follows that the thing I took a picture of existed unperceived at that time. But now it is clear that this whole language of the camera 'taking pictures of things' assumes that Realism is true and hence begs the question. In other words, it is an interpretation of the evidence to suggest that I took a picture of something which existed unperceived at T3 and that thing is what I have a picture of at T4. The experiences I have at T1-T4 do not entail that interpretation. We should describe the evidence neutrally, in a way that doesn't just assume that something existed at T3 of which I took a picture. If we do that then the evidence I have is that I perceive something at T1, then I close my eyes at T2, then I press a button at T3 and hear a clicking sound, then at T4 I perceive a picture of something which looks like the thing I perceived at T1. None of that entails that things exist unperceived, so how do you cogently infer that things exist unperceived from this data? This would be an intriguing argument, if you could fill the details in.

As I said, you're only making it seem difficult and mysterious because you're mixing up the abstraction of the experience of the object with the object. This is also the reason why you think I'm begging the question, or defining things into existence.

Your experience of the laptop, certainly, cannot possibly exist unperceived. In the case of experiences as such, abstracted away from what they're experiences of, esse most certainly is percipi. — gurugeorge

This is the 2nd time you have accused me of this conflation. I am well aware of the difference, which Moore pointed out, between the experience of something and the object of the experience. I am not sure I even used those words in my last post. At T1 I perceive something. It is something which I would ordinarily call a 'laptop', but since you insist that if it is a laptop then it must exist unperceived, I do not call it a 'laptop'. Instead I try to characterize the perception in a way that doesn't presuppose Realism, by saying merely 'I perceive something'. This was also the reason I spoke of the 'object of my experience'. The 'object', as I was thinking of it, is merely that which I see. I see a black, rectangular thing with a slightly lighter front face. What I don't see, is the property of unperceived existence, which is why if the thing I perceive really has that property, I can only reliably tell that this is so by inference.

I completely agree with you that our language itself isn't metaphysically loaded. I think ordinary language is far less precise than most philosophers suppose that it is and doesn't have 'build in' views on philosophical issues. I think Bertrand Russell saw this clearly. I do think, though, that most non-philosophers believe that Realism is true, at least implicitly.

PA

, you say that I have been redefining words so as to create a mystery. From my perspective, it is you that is obfuscating things with words. Your insistence on never using a word in any sense other than the 'ordinary one' prevents any interesting discussion of a real philosophical issue. Let me try to state the problem again.

The problem is this. I am presently looking at something. This thing, which is in front of me, has a certain shape and size and colour. Does it still exist if I leave the room and no one is perceiving it? What you said in this connection is:

If it's truly a laptop you're perceiving then of course it exists unperceived. Laptops are just the sort of thing that exists unperceived, and you can check for yourself, in the way I outlined, that your laptop exists unperceived.

If you are talking about (abstracting away) your experience of the laptop, then it obviously doesn't exist unexperienced. — gurugeorge

But this is clearly just a semantic trick devised to dodge the substantive issue. Yes, the way we ordinarily use the word 'laptop' is such that 'laptops' exist unperceived. Fine, forget the word 'laptop'. The thing which I am looking at right now, does it exist unperceived? Yes, I ordinarily think that it does and I ordinarily use a word, 'laptop' in such a way that 'laptops' exist unperceived, but this is all irrelevant. I am presently asking whether what I ordinarily think is actually true, and whether I have any reliable means of figuring it out. That I use the word 'laptop' in a realist way is irrelevant.

So not only are you giving me an idiosyncratic definition of "doubt" without giving me any reason why I should follow you in your redefinition, you're also giving me an idiosyncratic definition of "object" without giving me any reason why I should follow you in that redefinition.

You may think you're revealing something profound and interesting, but from my point of view you're just redefining words in a way that creates a queer artificial mystery. No mystery exists in relation to the normal uses of the concepts, the mystery, the puzzle, only appears when one takes seriously your proposed redefinitions of those concepts.

But you will forgive me for being sceptical: why should I re-jig my concepts so that "object" means "experience-of-object?" — gurugeorge

Don't 'rejig' your concepts at all. Leave them where they are. Use the word 'laptop' so that it means something which exists unperceived. My question then is, is that thing in front of me at the moment a 'laptop'? That is, is it something which exists unperceived!

Don't follow me in my 'redefinitions' if you don't want. Just recognize that I am presently looking at something, and there is a fact of the matter as to whether that thing exists unperceived or not. I am wondering whether there is any truth conductive source for the belief that it does exist unperceived. If there isn't, that belief will turn out to be a baseless speculation. Whether you call it a 'laptop' or not I don't much care. Whether you say the issue is one of 'illusion' or not doesn't matter to me. Whether we describe the issue as about 'doubt' or not is something you can decide.

You don't need a bundle of special concepts to create an issue here. The issue is that there appears to be no reliable way for humans to have come to believe that Realism is true.

A painfully simple way to see the difficulty with your argument here is as follows. Every Theist means by 'God', a being which actually exists. Does it then follow that God exists, just from the fact that the Theist uses a word a certain way? Surely not, but if not, why should it follow, from the fact that I use the word 'laptop' to mean a being which exists unperceived, that the thing actually exists unperceived?

The dogmas of the day are often etched into the meaning of our words, but one shouldn't think that the fact that they are so etched means that they must be true, or that they are beyond question. Not even Austin, the paradigm ordinary language philosopher, thought that.

As a side note, I deny that there is any such thing as 'the ordinary language concept' of anything, beyond a vague association of a word with other words, together with a list of examples to which the word applies. I don't think ordinary people have very precise concepts at all, or that people all have the same concepts so that it makes sense to say that there is 'the ordinary concept'.

You must use language to doubt, no? Which is to assume that language is coherent and represents what you wish to doubt in such a way that doubting it could make sense — Janus

You raise an interesting question. Can I coherently doubt that my language means what I think that it means? I believe Kripke discusses this at length in connection with Wittgenstein. I am honestly not sure of the answer, though I think its a fascinating question. It depends what is meant by 'meaning'. I would think several different explications of the concept are possible, which extrapolate from a vague ordinary notion, and the question may have different answers on different explications.

I have enjoyed the thread too. I want to read over the discussion between you and Wayfarer. Perhaps in the morning when I am less tired.

PA

Doubt is not suspension of judgement, it's the questioning of the truth or validity of something based on reasons (e.g. some anomaly). Suspension of judgement would be something like agnosticism or indecision. — gurugeorge

Alright, so you define 'doubt' as the questioning of truth based on reasons. Then you conclude that its incoherent to doubt something without reasons. Well I suppose your argument is correct, if only because its patently trivial. If that's what you mean by 'doubt', then I do not claim that we can 'doubt' everything. I claim the theses which I mentioned in my last post, all of which you ignored.

If they are truly objects of perception, then necessarily they exist unperceived, so doubting that objects of perception exist unperceived doesn't make any sense. Generally, with odd exceptions like rainbows, objects of perception just are the kinds of things that exist unperceived (or: if it doesn't exist unperceived, then it wasn't an object of perception after all). You can easily verify the existence of unperceived objects by means of instruments (e.g. using a watch, shut your eyes and simultaneously take a picture with a camera with a timestamp). — gurugeorge

You can't just define 'objects of perception' as 'things which exist unperceived' and then claim to have won some victory. I am currently having a certain sensory experience as I type these words. It is an experience I would describe as 'of a laptop'. The object of my experience is just that which I am aware of at that moment. Does that thing, 'the laptop', exist unperceived? Its clearly false that, as you say, 'objects of perception necessarily exist unperceived', since the present object of my perception could very well only exist when perceived. There is no contradiction in supposing that the laptop which I am currently aware of does not exist when unperceived.

You could define 'object of perception' so as to make yourself right, but that's hardly impressive. I think the disagreement we have had here is because you took me to be using 'object of perception' in a different way than I was.

Yes, but you've given us no reason to take it seriously and to replace our ordinary use of "illusion" with it. It's just an imaginary usage, a flight of fancy that bears little relation to the ordinary, everyday concept of illusion. The ordinary use of "illusion" is contextual - illusion in relation to veridical perception, and one doubts perception based on reasons. Imagining a deceiving demon isn't a reason to doubt perception — gurugeorge

Why do I need to give you a reason to accept a stipulated definition? I told you what I mean by illusion. An object of perception is illusory if and only if that object does not exist unperceived. If that isn't the ordinary usage, that's nice, but why does that matter? If you just don't like me using the word 'illusion' in a non-ordinary way, then use the word 'smillusion' for my concept. Is the ordinary concept somehow the word of God, so that I dare not ever introduce a non-ordinary concept for the discussion of a philosophical issue?

You don't need to imagine the demon for my purpose. I remind you again that I have no thesis about doubt understood in the way you understand it. I have maintained (1) We cannot prove to someone who does not believe it that the objects of sense perception exist unperceived, (2) we cannot even locate a reliable source for that belief to the satisfaction of realists themselves. I have discussed attempts to refute both of these theses (since I hope at least the 2nd one can be refuted) with several others. I can't find any argument in what you say against either (1) or (2). I can only find the insistence that we define 'doubt' in a certain way, that we define 'illusion' in a certain way, the ungrounded claim that 'the objects of perception necessarily exist unperceived' and the assumption that if a concept isn't an ordinary language concept, we aren't allowed to use it.

PA

, this all seems largely misconceived.

Any "why believe that?" question can be answered normally. Why believe there's a table in front of you? Because you can see it, it's got the functional form of a table, you can rap on it, etc. Those sorts of things are the standard for answering "why believe?" questions. — gurugeorge

I grant that that is how we normally answer 'why?' questions.

You can't extend doubt to everything because, as I said, you can only doubt on the basis of some other things held to be true, because that's how doubt works, it's leveraged off of truths. Truth comes first, doubt is secondary. Truth is the usual state, doubt departs from it and returns to it. — gurugeorge

Why can I only doubt on the basis of some other things held to be true? I am assuming that by 'doubt' here, you mean suspend judgement. I am not sure what else could be meant. But why can't I suspend judgement on everything without believing other things to be true? Its all well and good saying 'that's how doubt works', but that isn't to answer the question I have asked, but just to restate your view with the qualifier 'that's just how it is'. Hardly a satisfying argument.

For example, you can only say that something is an illusion on the basis of some other corrective perception that tells you it's an illusion. But that means you're accepting the corrective perception as valid. But that means you can't doubt whether all perceptions are illusions, only some...

IOW, if there's such a thing as illusion anywhere, then there logically must also be such a thing as valid perception somewhere, because without valid perceptions no such thing as illusion could possibly be revealed (or: "illusion" would have no meaning). They're inextricably tied together, depend on each other for meaning, so the idea of "extending" doubt to all perception is incoherent, it seems like something you might be able to do, but you can't actually do it, except as an imaginary exercise. But no truths hang on the use of the imagination. — gurugeorge

Your example brings out a misunderstanding of the role that sceptical hypotheses play in my OP and subsequent posts. I am not merely saying "oh well all of life might be an illusion. I suspend judgement on whether it is or not." I never made that suggestion. My suggestion was two fold. (1) We cannot prove to someone who doubts it that the objects of sense perception exist unperceived, (2) we cannot even locate a reliable source for that belief to the satisfaction of realists themselves.

But let's think about illusion. What is meant by saying that my current perceptual experience is an illusion? It surely just means that the object of my current perceptual experience is one which doesn't 'really' exist, and what does that mean? It means just that the object of my current perceptual experience doesn't exist when I am not perceiving it. The difference between an illusion and a veridical perception is that the object of the latter, but not the former, is supposed to exist unperceived. If this is the concept of 'illusion' involved, then there is nothing incoherent about supposing all of life to be an illusion at all. To suppose that would be to suppose that every object of every perceptual experience one has is one which does not exist unperceived. And to think that the evil demon hypothesis is true is to think that every object of every perceptual experience one has is one which does not exist unperceived and that an unperceived evil demon exists which is the cause of perceptual experience. What's incoherent about that? It sounds like a perfectly coherent story of how things might be. I have given a perfectly clear meaning of 'illusion' which doesn't at all depend on any of our perceptions being veridical.

so the hypothesized BiV predicament can't possibly cast doubt on all perception, only one's own. But we already knew that our perception can be mistaken, that's why we sometimes check things by asking other people. — gurugeorge

Of course, if I am doubting whether any of the objects of sense perception exist unperceived, it is the objects of my sense perception about which I am doubting. It is true that perception can be mistaken and that we 'already knew that', but this is irrelevant to either (1) or (2) or my ability to entertain the evil demon hypothesis.

PA

, you disagree with my account of how people come to believe that Realism is true. You say that it just isn't convincing. For my part, I find the idea that a metaphysical interpretation of reality is biologically hardwired into the human race for survival purposes (what other purpose could the hardwiring serve, given natural selection?) incredible.

I do not have much stock in this however. It doesn't really matter to me whether it is hardwired or not. I was only interested in that idea insofar as it concerned the argument that 'because realism is hardwired into us, it is probably true', an argument which I reject entirely. It seems that you agree with me that there is no reason to think that Realism is true. I'm not sure yet what should be done about that fact. Of course, Idealists think we should just drop the assumption. I do think, however, that if we are right about the baselessness of Realism, that realization should instil a kind of modesty when criticizing worldviews different to our own, and I think that's a valuable consequence of this kind of philosophical discussion.

You're using a realist argument to help PossibleAaran defend realism — T Clark

The person you quoted is PossibleAaran, ie, me. Also, the argument I gave in the quotation isn't an argument in defence of Realism. I denied that Realism is 'in built' and suggested that it is taught to us as children. I haven't defended Realism at all in this thread. I have consistently said both that there is no way to prove Realism to those who don't accept it, and that the Realist can't even locate a reliable source for his belief in unperceived existence, even a source which Realists themselves recognize as reliable.

So I can't make much sense of what you said here.

Generalized doubt, Cartesian doubt, or global scepticism, is fundamentally incoherent, especially if it's based on merely imagining that things could be different than they appear to be (imagining alternative "logical possibilities"). To doubt, you need a reason to doubt, not just a contextless wondering whether things might be different than you think they are. — gurugeorge

it can't coherently be elevated to a permanent cognitive stance that doubts everything. — gurugeorge

I have heard this argument several times, usually from Wittgenstien's followers. But why is it incoherent to doubt everything? There is no explicit contradiction, so can you make the contradiction explicit? Its obviously true that ordinarily we don't doubt everything. We hold some things fixed and doubt other things within that context. But I've never seen a reason to think that there is anything incoherent about extending the doubt to everything.

You said that 'you need a reason to doubt'. I don't think so. All you need in order to doubt something is the ability to ask 'why believe that?'. So long as I can ask that question, I can doubt, so why can't I ask that question with respect to everything I believe?

PA

Sorry for the double post, but perhaps I should add to the above that most people have never even noticed that Realism is something which they believe, although they would accept it if you brought it up. Until you do philosophy, it is very easy to completely fail to notice your own Realism or that there is an alternative. That is another reason why the teaching goes so smoothly.

PA

I don't suppose that every single child in the history of the earth is surprised by peek-a-boo, no. But, as I said, many Realists put forward, as a reason for thinking that Realism is true, the claim that Realism is an instinctive belief pre-programmed into us. But the fact is that many children are surprised by peek-a-boo. Many children do seem to think that you cease to exist just because they can no longer see you (it is hard to tell whether they really think this, since you can't ask children at that stage what they think, and when they get to the stage where you could sensibly ask them, they won't remember what they thought!). I am not suggesting that all think this way, but many do. What this shows, is that Realism is not 'built in', but is in fact learnt.

And yes, I suppose that the teaching of Realism to children is incredibly successful. Why don't children rebel from their teaching and reject Realism? Well, W.T Stace did, as did the whole Idealist tradition. No doubt they are a minority of the human race. I think the more satisfying answer is that people don't normally bother to question things which make no practical difference, unless there is good evidence that it is false. We are all taught as children that Santa delivers our presents on Christmas, and I believed this without question until I was told by numerous people that it was false, I saw my mother bringing my presents into the house, I was 'teased' by older children about how Santa isn't real. If none of that had happened, I would have just gone on believing it, since it made no practical difference to me at that time, whether my mother or Santa gave me the gifts. There was just no reason to question it.

The same is true of Realism, we are all taught as children that things exist unperceived - or this is implied by other things we are taught - and we all swallow it just like we swallow the Santa story. We never question Realism because it makes no practical difference whether it is true or not, and there is no evidence against it. This, together with the fact that it is very easy, if you don't do philosophy, to mistakenly think that you can 'just tell' by sense perception that Realism is true, mean that Realism goes unquestioned for the majority of people.

You can't teach your children manners as effectively because it often takes excessive effort to be polite when we are in a bad mood, or when being rude would be much more efficient for our purposes.

PA

It's because young children don't know that something is still there when they cover their eye — T Clark

Some philosophers, I believe following Bertrand Russell, have defended Realism by saying that it is an instinctive believe 'built in' to all of us and which we cannot help but have (Javra has a very similar argument above). I've never been too sure what to make of that argument. What you say here points out that this claim is obviously false. Your point is so obvious that I can't believe I didn't see it. My niece is at just that stage in childhood right now, and yet I still didn't pick up the philosophical relevance.

Thanks for this.
PA

Wouldn't realism being the most likely inference from experience qualify? We don't need to posit demons or computer simulations. We can just say the things in perception continue to exist while not being perceived, along with other things we can't perceive, but we can infer from things perceived, like elementary particles.

That goes well with science, which doesn't infer demons or simulations or brains in vats, but does infer plenty of unobservables that make good sense of what is observed, along with object permanence. — Marchesk

The inference you suggest would be just the kind of things which is needed, but what makes Realism a better explanation of experience than the evil demon hypothesis or a brain-in-vat hypothesis? In fact, why is such an explanation even necessary? Isn't it ontologically simpler to suppose that things only exist when perceived?

In the Kantian approach, sentience holds within it aprior understanding of causation in the abstract, thereby facilitating belief that things causally continue to be even when not perceived or thought of. — javra

I am not sure what this argument really is. I am supposed to have a 'prior understanding of causation in the abstract'. Does that mean that I innately have a concept of causation? If so, how does that show that the belief that things exist unperceived has a reliable source? (1) I am not sure what relevance causation has to whether things exist unperceived, and (2) even supposing it has relevance, it does not follow from the fact that I have an innate concept of X, that X is a correct description of the world, unless you are supposing that all innate concepts are reliable, but that's empirically false.

In a strictly evolutionary approach, were intellect-endowed sentience (sapient or otherwise) to not have evolved unconscious aptitudes for discerning how things continue to be when not perceived or thought about, the given sentience would perish; lifeforms would either be, for example, quickly killed by stealthy predators or predators would quickly starve to death. — javra

Is it true that if we didn't believe that things continue to exist when unperceived we would die? I am inclined to deny it. Could you give an example in which it is clearly true?

In addition, let's suppose that evolution gave us this belief. Evolution just 'programmed' this belief into our minds for the sake of survival. Is that a reliable source for belief? Couldn't all kinds of beliefs be useful for survival and yet false? The belief that tigers have submachine guns hidden in their fur would be useful for survival. It would sure keep me away from tigers, but it is obviously false.

PA

, interesting post.

What makes realism more plausible than an evil daemon? One element to this is as follows: Conviction in realism is how I and a majority of the world’s populace—both greatly and poorly educated (education being a separate issue from that of intelligence for me)—navigate the world most pragmatically, for it facilitates an optimal flourishing of awareness in regard to worldly givens. The evil daemon hypothesis, however, presents a lack of reliable predictability as to what will be, and posits no way of reliably establishing what is—and, because of this, is debilitating to the living of life. — javra

The difficulty with the above argument was that, as I stressed to Marchesk, the sceptical problem I was alluding to consists in the fact that humans appear to have no reliable means of establishing that anything exists unperceived. The argument that Realism makes living life a lot easier has no obvious bearing on this issue, since believing what makes my life easier is not obviously a reliable source of truth. It is true that the evil demon hypothesis posits no 'way of establishing what is', but why should that make Realism more likely to be true? The argument appears incomplete.

My former, yet unanswered question to you was “what justifies the favoring of an evil daemon as true at expense of realism being true?” An answer would now be appreciated. — javra

I am not sure that there is anything that favours the evil demon hypothesis over Realism. But we are presently looking for some reliable source for the belief in Realism, and this question has no bearing on that.

The title of this thread is “what is scepticism”. In your reoccurring arguments you overwhelmingly favor Descartes’ branch of skepticism, even though in your OP you thoughtfully point to different branches of belief that likewise go by the label of skepticism. — javra

You are not the first to (a) interpret Descartes (mistakenly in my opinion) as driven by an unfounded obsession with certainty and (b) assume that I am also driven by the same obsession. With respect to (a), Descartes wanted his metaphysics to be 'stable and lasting'. He wanted it to have so great a dialectical advantage over any alternative position that it could not be overturned, like Aristotle's system was being in Descartes' time. That's why he sought certainty, and that seems to make perfect sense to me, even if he didn't succeed in the end. The interpretation of Descartes has little bearing on the present issue, so let's move to (b).

I am not engaging in the

endless stream of debilitating doubts in search for some inexistent grail of absolute certainty. — javra

I would be happy if anybody could show that Realism was even slightly more probable than the alternatives. You don't even need to show that it is more probable using only premises that a radical sceptic or an Idealist would accept. I would be content if you could tell a story about the faculties of human beings which is such that (c) Realists believe that it is a true account of their own faculties, and (d) listed among those faculties is one which reliably produces the belief that things exist unperceived.

Let me illustrate with a religious example. Alvin Plantinga is well known for his 'Warranted Christian Belief'. What he does there is tells a story in which human beings possess this cognitive faculty, 'the sensus divinitatis', which reliably produces the belief that God exists (or more exactly, beliefs like, 'God is pleased with me', 'God is ashamed' and the like). If humans have a sensus divinitatis, their belief that God exists is probably true, since it is produced by this reliable faculty. Plantinga admits that he has no way to prove to atheists and agnostics, using only premises which they accept, that we have a sensus divinitatis which reliably produces the belief, or that God probably exists. Still, the story he tells is one which, if true, entails that God probably exists. It is also a story which Theists find plausible; they believe that we have a sensus divinitatis.

I would be content if you could tell a story like Plantinga told, but for the belief that things exist unperceived. If you could indicate any method at all which is such that (e) it could reliably establish that Realism is true, and (b) Realists actually believe that humans can use this method, I would be content. You do not have to prove that the method you imagine is one which humans could use, using premises only acceptable to sceptics and Idealists. You need, in short, only imagine a method which you can convince yourself is actually available to you. The problem is that Realists are typically unable to do even that. They are typically committed to Empiricism, the thesis that the only reliable sources of belief about the world that we have are sense perception and inference. Sense perception is not reliable about unperceived things, and no one, as yet, has been able to provide a non fallacious inference to the conclusions that things exist unperceived. And hence, their own account of human cognitive faculties is such that we have no reliable basis for the belief that Realism is true.

At any rate, if you seek solace via some promise of an absolute certainty—be it that realism is true or that some evil daemon concept one is momentarily entertaining is false—I’m not one to be of service in this regard. — javra

I don't think what I have asked for is certainty at all. All I have asked for is that the Realist have some account, which he can at least convince himself is true, of how human beings can have any reliable basis at all for the belief that Realism is true. What I have asked for is incredibly weak. Even Plantinga is able to muster this much for his belief that God exists, and most people think that what he is able to do is quite trivial.

PA

What do you mean by never having found any reason? Do you mean any reason the idealist would accept? I think there are good reasons for being a realist. They might not be good enough to convince an idealist or skeptic, but that's their problem. — Marchesk

Let me distinguish two different conceptions of reason, and I say you have supplied neither of them in favour of Realism.

Reliability

Humans have two reliable sources of belief about the world. Sense perception and inference from sense perception. Sense perception is not reliable with respect to things unperceived, since sense perception is, obviously, only a reliable source of belief about things sensed. The property of unperceived existence cannot be sensed. Therefore sense perception is not a reliable source for the belief that Realism is true. (I think this is the very least that should be said. W.T Stace thought that the very idea of sense perception is reliable with respect to the unperceived was contradictory). This leaves inference. But the only inferences which you tried to make were question begging; they assumed what was to be proven, and question begging inferences are unreliable. This is one sense of 'reason'. S has a reason for believing that P if and only if S has some reliable means of acquiring the belief that P.

All one needs to 'have a reason' in this sense is to locate some reliable source for the belief, regardless of whether or not an Idealist or a Sceptic would believe that that source is reliable. Can you even locate a reliable source for the belief which even a Realist would accept is reliable? Sense perception and inference have been ruled out since sense perception is reliable only about what is sensed and the only inferences we have found so far have been fallacious.

Dialectical

You mentioned the power of reasons to convince, and you said that Realism has good reasons in its favour, just not reasons 'good enough to convince an idealist or a sceptic'. Well, as I pointed out, the only reasons you gave for believing Realism to be true were question begging and so powerless to convince any sensible person who does not believe Realism already. What is the point of a 'reason' which cannot convince someone who is not already convinced by the doctrine you are attempting to prove?

You posit the evil daemon to be inconsistent to realism—the latter, by your definition, being the stance that one or more things can hold presence when not perceived or thought about.

To understand your “skeptical” point of view better:

Does the evil daemon hold presence when not perceived or thought about?

Secondly, is everything that one thinks true (here, correspondent to what is real)?

BTW, it wouldn’t make much sense for me to answer your questions when mine are not first answered … since I’d have little if any understanding of your own stance. — javra

The evil demon hypothesis does posit the existence of a demon which exists when unperceived. The contrast between this hypothesis and Realism is that Realism maintains that the objects which are perceived by us exist when unperceived, and the evil demon hypothesis denies that. (I should mention that there is also what goes by the name 'indirect Realism' according to which the objects we perceive are 'mental' and exist only when perceived, but there are other objects which these mental objects are pictures of and which exist unperceived).

I do not think that everything that I think is true, although I am not sure I have understood your second question correctly.

No, I do not think so.I think this is more like the case of Catholics calling Protestants "atheists", failing to describe their thinking.
Skepticism was also for many years in the modern period (late Medieval) a term of abuse directed from those that were happy with their certainty, especially about God, against those that preferred to ask questions.
`By the religious establishment a good dose of healthy skepticism was seen as a major danger and was traduced as a "burning issue" in a literal sense.
But those self identifying as skeptic would have a more positive view of their position, as do I. — charleton

I am not sure what the point of this is. Are you merely insisting that the word 'scepticism' describes your position and your position only? If so, that ignores the evident fact that philosophers have used the word 'scepticism' to refer to many different things. I am not sure why you insist on it being used in only your sense.

I think what the realist does, and this is something Schopenhauer is explicit about, is that s/he forgets to take account of him or herself, the sense in which all of our knowledge of the world is mediated by the senses, assimilated by the understanding, and represented in the intellect. Realism, generally, doesn't critically reflect on the nature of experience, and the contribution the mind makes to it. — Wayfarer

Perhaps, although one needs to be very careful about what the minds 'contribution' is supposed to be. I am looking at my laptop right now and as a result having a certain sort of sense experience - I am sure you know roughly what it is like. What, exactly, does my mind contribute to that experience? What I am tempted to say is just that I look and I see the laptop. My mind isn't adding anything. The laptop is there before my consciousness. But I recognize that this is likely far too simple to be true.

PA

You would need to ask an Idealist how he knows that there are other minds, and why he cares about a rain forest which only exists when people perceive it. I'm new here and I don't know if there are any Idealists around. Since I am not one, let's just concede that he has no answer to either question. The fact that Idealism has consequences which sound strange to us isn't a reason to think that Realism is true. Strange as Idealism is, we never found any reason to think that things exist unperceived.

PA

I'm not seeing how either of these examples are not a matter of degree. Our faculties can be quite reliable, very reliable or completely unreliable, no? Likewise we can consider our belief completely unprovable to others, quite convincing or virtually impossible to refute (but retaining some small doubt). In each case our actions (or other response) are surely more guided by our beliefs about the extent of our skepticism than by its existence or not. — Inter Alia

I see your point. They are a matter of degree, but the challenges posed by sceptical writings have typically been absolute. So the thought is that we have no reliable means at all of establishing that things exist unperceived. Sense perception is reliable to a degree with respect to things observed, but it is not reliable at all when it comes to beliefs about things we have not observed. Stace argues in his refutation of Realism that its actually contradictory to suppose that sense perception is reliable even in the slightest concerning unobserved entities. Similarly, whether we can prove our beliefs to others is a matter of degree. I might be able to prove them to people who accept certain assumptions, but be incapable of proving it to someone who doesn't. Ancient sceptics thought you couldn't, ultimately prove anything to someone who was prepared to doubt far enough. They might have agreed that some things can be proven given this or that assumption. Thanks for making this point, which I had failed to see.

If I took the skepticism about the unperceived world seriously, then wouldn't I doubt whether those issues even exist when I'm not perceiving them? — Marchesk

Not necessarily. I might maintain that we have no reliable means of establishing that things exist unperceived, but I might still continue to believe it. I might admit that I have no rational basis for the belief, but still believe it, just because I can't help it. Of course, that's not the route the Idealist takes, but it is a possible route.

As long as I'm not perceiving starving kids in Africa, terrorist cells, or the rainforest being cut down, then why should they be of any consequence? For all I know, they only exist when they come into view.

Maybe the better approach would be just to avoid seeing those issues so as to keep them nonexistent, if esse is percipi. — Marchesk

If I were to take the Idealist route, I would likely answer you like this. The Idealist view is not that nothing exists unperceived by me, but that nothing exists unperceived by some mind. The starving kids in Africa obviously perceive themselves and their starvation, so the Idealist need not say they don't exist. The same with terrorists. The rain forest being cut down is obviously being perceived by the people cutting it down.

But we do have cases where we open our eyes and see that the laptop is frozen up instead of delivering a result. So we have different possible scenarios upon opening our eyes:

The laptop displays a finished computation.

The laptop is frozen up.

The laptop is out of power.

The laptop has overheated.

The laptop is gone!

And so on. Brutely speaking, we can't say why any of the above happened. We open our eyes, and there's a new experience to be had. But we can provide realist explanations. The laptop is gone because someone else took advantage while our eyes were closed. Perhaps philosophical skepticism at a busy bus stop is a bad idea. — Marchesk

The explanation in terms of 'someone taking advantage' is available to the Idealist. Since the 'someone else' perceives the laptop as it is being stolen by him.

PA

There seems to be an excessively binomial use of the term 'Skepticism' here - either one is skeptical or one is not, but surely skepticism, by whatever definition, is a matter of degree? — Inter Alia

I'm not sure about this. In the sense of 'Skepticism' as 'doubt' then sure, it is a matter of degree. But that's not the only meaning of 'Skepticism' that has been intended in philosophy. Many have used it to mean that our beliefs lack a certain credibility status; perhaps that our faculties aren't reliable about certain matters, or we can't prove our beliefs using premises acceptable only to someone who does not believe them. Just two examples.

As one example, were a single light in the home to no longer turn on when I flick the light switch, the realism of an external world would indicate that there is something physically amiss with the light switch, the respective lightbulb, or with the wiring that dwells in between. The real problem might not be perceived nor thought of at first, yet the web of causal relations which such realism affirms facilitates my being able to discover what is wrong so as to resolve the problem. Other hypotheses, such as a Cartesian evil demon (or the materialist counterpart of being a BIV), could be conceived as alternatives to the reality of an external world. Yet, devoid of upheld belief in the very same external world, these alternative hypotheses would at best only encumber my ability to remedy the stated problem. This then can be expanded to why electricity operates the way that it does, to the question of where the electricity in my home originates from, etc. — javra

I'm not sure how something like the evil demon hypothesis 'encumbers your ability to remedy the stated problem'. You know from experience that when you turn on a light switch and the light doesn't come on, you probably need to change the bulb. That seems just as true on the evil demon hypothesis. The only difference is that neither the light bulb, nor the switch, nor the wiring exists when you aren't in the room, since these things are just projections of the evil demon. But that they are projections doesn't make any difference to how you would go about solving the problem. The advocate of an evil demon hypothesis can also easily accept all of the usual explanations about how electricity operates and where it comes from in your home. The only thing he denies is that any of these states of affairs obtains while unperceived. Still, I do think you might be on to something and I think its worth taking the time to flesh it out more. What, exactly, is it about the denial that things exist while unperceived which is explanatorily deficient? What questions, exactly, can't be answered by the evil demon hypothesis as well as they can be by Realism, and what is better about the Realist answers?

The question to me is one of why uphold something like the Cartesian evil demon rather than an external world? I.e., what justifies the upholding of such a conviction? — javra

What justifies the upholding of Realism? Are you assuming that unless there is some reason to think the evil demon hypothesis is true, Realism is somehow 'by default' more likely to be true?

For example, it is common knowledge that Plato, an idealism-leaning philosophical skeptic, was a realist. It seems logically sound to me that Buddhists, by virtue of upholding Nirvana to be, are all realists--regardless of possible divergences as concerns other aspects of ontology—for Nirvana (and the four Noble Truths) would yet be even if all sentience were to somehow be, or become, unenlightened (in the Eastern sense of this term) … in other words, the Buddha didn’t invent an axiom of Nirvana but, instead, discovered Nirvana's existential presence via enlightenment (this, of course, in Buddhist worldviews). Materialist realism is, of course, yet another variant of realism—one that strictly upholds an underlying physical reality (here thinking of QM, the vacuum field, etc.). In all cases, there are one or more things postulated to be even when not perceived, thought of, or talked about by anyone. — javra

I agree. Plato is a Realist in the sense that he holds that the Forms exist whether any one perceives them. He is an Idealist in a different sense to that in which Berkeley or Bradley or Stace were Idealists. The latter have in common the thesis that all that exists are minds and their perceptions. Plato held, by contrast, that the perceptible world is a mere shadow of a deeper Reality. Very different views.

Skepticism is the tendency for beliefs in representational theories of perception to collapse into beliefs in direct-perception and vice-versa.

I don't like discussions of skepticism in relation to idealism or realism, since both idealism and realism have been interpreted through the lens of representational metaphysics, and it isn't clear that either position constitutes a substantial ontological thesis. — sime

Could you be more precise about what a 'representational theory of perception' is? Then perhaps we could discuss further.

Also, take Realism to be the thesis that some entities sometimes exist when no one is perceiving them (W.T Stace's definition). Take Idealism to be the denial of Realism. What about this presupposes a 'representational metaphysics'. I suppose I'm still not sure what that means, but these seem like substantial ontological theses to me.



Unfortunately I think you are still begging the question.

The problem with this is that we understand computation to be a process. The laptop at T2 can't complete a computation without having undergone the process of computing starting at T1. — Marchesk

We do understand computation to be a process, and the Idealist maintains that there is no such thing as unperceived computation. Computers undergo this process when we perceive them to, but they do not do this otherwise. They don't even exist otherwise. A laptop which exists at T1 is in state X, and A laptop which exists at T2 is in state Y. To assume either (a) that both are the same laptop which endures over time or (b) that the laptop undergoes a process between T1 and T2 called 'computation' while no one is perceiving it is just to assume what needs to be proven. True, we ordinarily think of computation as a process over time, but the Idealist is saying that what we ordinarily think, is false.

But given that we're doing philosophy, a strong reason to trust the realist inference is because when we do watch our laptops, they undergo a process of computation from one state to the next. So we have no reason to think they don't just because we've closed our eyes. — Marchesk

We have no reason to think that they don't compute when we close our eyes, but we have no reason to think that they do either, without some sort of inferential argument. Having no reason to think that it is false that X is not a reason to think that it is true that X.

Big "S" skepticism seems lazy and cowardly to me. Come on Rene - don't give me this "cogito ergo sum" bullshit. Make up your damn mind. As I said previously, that type of skepticism is a luxury for those who can afford to sit around on their asses. — T Clark

I wouldn't want to deny that Big S Skepticism is not an issue which concerns people with more pressing 'practical' concerns, whatever they might be. But I would make two points. First, if the sceptic (of the sort I indicate in my last paragraph of the OP) is right, then we have absolutely no reliable source of belief in the existence of unperceived things. Such a belief has on rational basis at all and is of the same kind as the belief that there is a unicorn on mars (notice it isn't just that I can doubt this belief if I want to be an annoying and frivolous doubter. Rather, there is absolutely no rational basis for the belief at all). Now I don't deny that many people have things to do of a more consequential nature. If you are concerned with getting food for the starving, protecting the rainforest, saving endangered species or lessening terrorism then this kind of scepticism might seem abstract and useless. But I think if this sort of scepticism is right it teaches something very important. It is quite common for people of all kinds to deride different and unfamiliar belief systems, or even familiar but unpopular ones. It is even more popular to say of such systems that 'we know better' or that they are 'not based on evidence' or whatever other epistemic criticism. The realization that even our belief in unperceived existence is completely unfounded should encourage a great modesty and give pause when making that sort of evaluation.

Aren't you and Wayfarer mixing up two different types of skepticism? When Descartes says "cogito ergo sum" he is talking about facts. Do I exist? Does the world I see exist? Is the capital of France Paris? When you talk about skepticism about Naturalism, you are questioning the metaphysical basis of a whole system of belief. Those seem fundamentally different to me. The only problem I really have with Naturalism is that its proponents seem to believe it provides some sort of privileged outlook on the nature of reality, which I strongly believe is wrong. — T Clark

I am not sure I was mixing them up. When Descartes asks whether the whole world is a mere dream, he is effectively asking whether esse is percipi in waking life, as it is in dreams. If it were, that would surely entail that Naturalism is false? Although, it is hard to tell whether it would, since Naturalism is hardly ever clearly enough defined for one to tell what state of affairs would make it false!

I should note that I am not here suggesting that Descartes would have understood his topic this way. It seems to me that Descartes had very specific aims and goals behind his use of sceptical themes, and that these aims and goals are quite different to those of other writers who have used the same themes.

Is this an acceptable inference - To the best of my memory, every time I saw something and then closed my eyes, one of two things happened when I opened my eyes again. Either it was still there or I could find an explanation of why it wasn't there. If there were times I don't remember when I couldn't find an explanation, I am confident enough in my understanding of the world to believe that there was an explanation even if I couldn't figure out what it was.

That seems trivial to me. — T Clark

All of it seems true, but none of it entails that things exist unperceived, and I can't see anywhere that you even conclude that that is even probably true. I agree that every time I saw something and then closed my eyes, it was typically there when I opened my eyes again. I also agree that if it wasn't I could provide some explanation of why it wasn't. But why does this give me any reason to think that anything existed when I did close my eyes? What I am saying is, your inference might work, but it needs to be made more explicit what the inference is.

It seems to me that the evil demon hypothesis or one where reality is just a program running on a computer are metaphysically equivalent to realism as long as we can never step outside the universe/program/demon's imagination to see what is really going on. If Morpheus, Neo, and the crew had never escaped the Matrix, could never escape it, what difference would it have made that it existed?

This is a fun thread. — T Clark

This one wasn't directed at me, but I disagree. Realism says that the objects which I perceive exist when I am not perceiving them. The evil demon hypothesis says that the objects which I perceive do not exist when I am not perceiving them. It also says that the evil demon exists even when I am not perceiving him, and he is the explanation of the existence of the things I perceive. If 'metaphysically' is read in the usual way as concerning 'what there is', it is clear that these two hypotheses are not equivalent at all. I imagine that you mean equivalent for practical purposes, given your later remark, 'what difference would it have made'?

Sorry for leaving such a long post, but there were many insightful posts to reply to. Only one remains:

Possibleaaran’s excellent thread. — Wayfarer

Thanks. It being my first thread, I wondered how much response it would get. Incidentally I agree with you that, relative to the history of philosophy, Materialism is a minority position.

PA

, Hi, nice to meet you.

Well, if the ontological argument fails then so does my argument. The more interesting thing would be a refutation from somebody who thinks the ontological proof is valid. — Meta

I think the ontological proof is valid. I don't know about sound, but valid certainly.

1. The greatest imaginable reality for me is to be the greatest being imaginable (called God). (Axiom - a greater me implies a greater reality for me)
2. God created the greatest imaginable reality for me. (Easily follows from God's definition)
3. It is greater to imagine this imaginable reality to be real. (Axiom - an existing great entity is greater than the same entity in imagination)
4. That imaginable reality mentioned above is real. (From 3. and the definition of God)
5. I am God. (From 1. and 4.) — Meta

2 is false. You say 2 follows from 'the definition of God', but you haven't given such a definition, so it isn't clear how we are supposed to assess what you say. You do say this:

If the creation of God isn't the greatest creation imaginable then I can imagine a being whos creation is greater than God's creation. That creator is greater than God which is a contradiction. — Meta

But what you say here is fallacious. Its obviously true that if God's creation isn't the greatest creation imaginable then you can imagine a being whose creation is greater. Call the second being 'Schmod'. It does not follow from this that Schmod is greater than God. Schmod's creation is greater than God's creation, but why should that entail anything about the greatness of either God or Schmod? It can only follow on the assumption:

(A) If X is the greatest possible being, necessarily, X only creates the greatest possible creation.

But why on earth would that be true? That's like saying that if Da Vinci is the greatest possible artist, he only paints the greatest possible pictures. But there could be some reason why he, on some occasion, chooses to paint an average picture, even though he could have painted the greatest. There is no reason why God could not be the same.

Moreover, even supposing that it isn't fallacious, it doesn't support (2), since the conclusion of the quotation is that God must have created the greatest possible creation. But (2) says that the creation is the greatest for you, and there is clearly a difference between greatest simpliciter and greatest for some particular person.

PA

Many of the issues discussed by philosophers aren't about things which drive capitalist society. Philosophers aren't much concerned with human resources, marketing, advertising, sales, money, or banks, nor with day to day jobs like plumbing, engineering, electrics or construction. That's why you don't see scores of jobs in philosophy, outside of teaching and researching the subject. Many employers like a philosophy graduate, since they are generally methodical, patient problem solvers, but the jobs involved won't be about philosophy; you will have to forget about philosophy and just apply the skills you picked up to make a business some money.

I wouldn't worry about philosophy not having enough impact. Philosophy is about ideas, and ideas influence men every bit as much as capital does. Philosophers rarely get credit for any impact they do have though, since if a philosophical idea gains popularity in a society, lay people will just claim it 'common sense' and say they don't need philosophers to teach it to them!

For me, I found that my interest in philosophy was far greater than any interest I had in business, commerce or utilities. I wound up just admitting, to my self and anyone who asks why I do philosophy, that I just don't care about all of those 'practical' things. The most practical I get is morality and politics, and most people find those things still abstract and useless. I just care about ideas, and discussing them with others.

Marchesk, I thought that you were maintaining that no inference was needed? In any case, I am not sure that the argument you suggest is subtle enough to do the job. Here is what you said:

Let's say your laptop is performing some computation that you can't carry out in your mind. You close your eyes and when you open them, the laptop has an answer for you. How did it compute that answer while it no longer existed?

We can make the thought experiment more involved. Let's say your survival depends on the laptop performing some computation. If it fails to when you close your eyes, then a bomb goes off, killing you. You close your eyes. No laptop, no bomb, except for that ticking sound.

That's why idealism is silly. You either end up with an extremely gappy world in between perception where events somehow still appeared to have happened, or you have to invoke something like God to keep the laptop and everything else in existence. We know what Berkeley opted for. — Marchesk

The first thing to note is that your characterization of the data is already biased in favour of Realism. You presuppose that the object which is before me when I look the first time is numerically the same object as the one which is before me when I look the 2nd time, and that already screams out that the object existed when I wasn't looking, or else, how could the same laptop have changed state while not existing, as you point out? But this isn't a fault with Idealistic hypotheses. It is a bias in your description. Describe the data without the assumption that the laptop is the same each time and the difficulty disappears:

My eyes are open at time T1 and I see that a laptop is in state X. I close my eyes and reopen them at T2 and I see that a laptop is in state Y. It is a Realistic bias to interpret this by saying that 'it looks like something happened when I wasn't looking'. Neither what I see at T1, nor what I see at T2, yields this information. So what explains the fact that I see something different each time? It could be that there is no explanation. That I see something different at T1 and T2 might be a brute fact about the universe. There might not be a single object, the laptop, whose different states I see at T1 and T2 which has some state or other even when I'm not looking. This doesn't require that the laptop changed over time when I wasn't looking even though it didn't exist. The Idealist doesn't postulate the laptop at all. Hence, Idealism doesn't lead to the kind of gappy absurdity that you suggest.

The dream hypothesis fails because dreams are not like waking experience. The evil demon hypothesis has nothing empirical in its favor, unlike laptops and trees and what not. We can't infer an evil demon, a simulation, or being a brain in a vat from what is perceived. But we can infer a physical world. The laptop performs the computation when you close it's eyes because it's still there. Simple as that. — Marchesk

Concerning alternative sceptical scenarios, it is true that ordinary dreams aren't like waking experience in a sense. But they are alike in an important respect. When I dream, I see things which do not exist when I am not seeing them. For dream objects, esse is percipi. Moreover, my mind is the cause of the dream and all of the dream objects. The dream hypothesis is the idea that (i) the objects seen while awake only exist when I am sensing them and (ii) my mind is the cause of the existence of all of those objects. The evil demon hypothesis is (i) together with (iii) an evil demon is the cause of the existence of all of those objects. What exactly is wrong with these two hypotheses? Why can we sensibly infer Realism as opposed to them? Sure, you say that Realism can be inferred and these can't, 'simple as that'. But that's just saying, and I could just say that the dream hypothesis is better than Realism, or that all of them are equally likely. Why is Realism to be preferred?

Javra, it pleases me to hear someone give the explanatory defence of Realism. I think if anything can answer the scepticism I alluded to in my OP last paragraph, it is this. But difficulties do remain. You say that Realism:

provide the greatest explanatory power to the greatest number of questions that could be asked of something experienced to pertain to an external world — javra

Which questions can be answered by Realism? Can they also be answered by Idealism, the dream hypothesis or the evil demon hypothesis? If so, in what sense are the Realist answers superior? Does the superiority of its answers entail that Realism is more likely to be true than the alternatives? I am quite confident that there is no question about experience that Realism can answer which the alternatives cannot, but the question of the adequacy of those answers is an interesting issue.

Do not worry if it takes some time for you to reply Javra. Thanks for your thoughts.

PA

Marchesk

Thanks again,

This reply which you have given is a common and understandable one, but I think it makes some subtle confusions which once made clear, reveal that a much more careful analysis is needed to deal with scepticism than this one that you have given.

The questions you ask beginning "when you close your eyes" and ending "finally see or touch it" are more ways of raising the same sceptical issue I raised about my laptop, so these are not at issue. But you go on:

You can adopt that form of skepticism just like you could argue that we can't know everything popped into existence five minutes ago with the appearance of age and memories intact. And to use Russell, you could also say there is a giant orbiting teapot. But what's the point of that sort of skepticism? To demonstrate that you can be a doubting Descartes? — Marchesk

Now these questions are very different. My original question was "by what reliable method can you believe that the laptop exists when it is unperceived?". What creates the difficulty is the Empiricist claim that there are only two reliable sources of belief about the physical world - sense perception and inference. Sense perception is reliable with respect to things which can be sensed. Sense perception does not reliably yield true beliefs about unobservables. I cannot use sense perception alone to reliably form the belief that there is exactly one alien insect on the furthest planet from earth. I have never observed any such thing, and sense perception is only reliable concerning things which have been sensed. That is why sense perception cannot deliver a reliable belief that the laptop exists unperceived - because the property of unperceived existence is unobservable. This only leaves inference, which is why there needs to be an inference from the observed laptop to its unobserved existence.

Notice crucially that the way I framed the issue above is not me being a 'doubting Descartes'. I am not simply doubting everything that can be doubted for the sake of it, regardless of whether it is probable or not. When I, playing the role of sceptic, doubt that the laptop exists unperceived, I doubt something which, if we cannot provide an inferential argument for it, there is absolutely no reliable basis for accepting. If no inference is provided, human beings have no reliable means of establishing that any object exists unperceived, not even with the slightest probability. So much for your criticism that I am pointlessly being a 'doubting Descartes'. I am being no more a 'doubting Descartes' than someone who refuses to accept the existence of atoms on the basis of plain unaided observations of trees and rocks. Without a scientific inference, such a person has no reliable means of figuring out that there are atoms at all.

You also raise a number of issues about memory. Your thought is that perhaps the world popped into existence 5 minutes ago with the appearance of age. Well, I seem to remember that the world existed at least ten minutes ago, when I ate meatballs. Of course, a doubting Descartes might question the reliability of memory. He might say "oh but maybe your memory is deceiving you and the world was created 5 minutes ago". He could say that, but that would be to raise a very different kind of sceptical problem than the kind I am trying to raise. My problem is that, even assuming all of the usual human faculties are reliable sources of belief, there is no reliable basis for the belief that an object exists unperceived, unless an inferential argument can be given. Hence, the issue I raise for sense perception has no parallel for memory. Memory is a reliable source of belief about the past. Sense perception is reliable about things that can be sensed, but is not a reliable source of belief about unobservables, and the property of unperceived existence is an unobservable. Hence, there is a difference between the radical sceptical issue you raised about memory and the issue I raised about sense perception.

Lastly, you write:

The much more likely answer is that our perceptions are possible because there exists an entire world full of people, objects and events to perceive that persists over time. That world is primary, not our perceptions of it. — Marchesk

But what makes it more likely? There are many alternative hypotheses which explain the observable data, and I'm sure you are familiar with them. The dream hypothesis. The evil demon hypothesis. Etc. What makes these worse off than Realism?

PA

Wayfarer, I haven't read The Last Word, but I just did a quick google. It looks like it contains critiques of both Naturalism and Relativism, and that interests me greatly. I agree with Nagel on many things, and so I'm surprised I missed this one. Thanks for pointing me that way.

In my reading about the life of Pyrrho, there are interesting anecdotes about his demeanour when he came back from the East - that he had to be looked after as he showed no sense of concern for his physical well-being, and also that he was highly tolerant to physical pain and discomfort. I think it's a hint that the 'suspension of judgement' went far deeper than simply the discursive. — Wayfarer

The story I find most entertaining is that Pyrrho had to be protected by his friends at all times even just walking down the street because of his complete disregard. He would walk without stopping toward deep lakes and refuse to move out of the way of horses! I think you are right that his suspension was perfectly general. Most of his followers thought his style of life was ultimately unmanageable and undesirable, which I think is what lead to the 'going along with' beliefs of common life. This attitude of 'going along with' seems to give the sceptic who practices it a kind of hollow appearance. He says officially that he does not believe these things, but behaves for all the world as though he did. I don't know how much force a criticism like this really has. I suspect such a sceptic wouldn't be too concerned by the charge of hollowness.

Marchesk

Or one could attack the veil of perception and the notion that we perceive sense datum instead of the objects themselves. Direct realism has an easy answer to external world skepticism. It denies the starting point for getting skepticism off the ground. And you don't need idealism as an answer to skepticism if we're already perceiving physical objects, obviously.

The difficulty for direct realism is accounting for various aspects of perception and experience that led to skepticism in the first place. But this effort has continued to the present day. Direct realism is defended by some modern philosophers. It was never actually defeated, just called into serious question. — Marchesk

That is the way many philosophers attack the sort of scepticism which Russell sets up with his veil. But I suggest that you have made a mistake if you think that there is no problem of external world scepticism once you reject the veil. I briefly indicated this in the last paragraph of my OP, but let me try a little more carefully. Suppose Direct Realism is true. In that case, this, which I am looking at right now is a 'physical object' and not a 'sense datum'. It is also what I call a 'laptop'. I can observe that my laptop has various properties. It is black. It is rectangular. It has a screen and keys. All of this I can observe and reliably believe. But now suppose I close my eyes. I am in this room alone at present. Is there still a laptop there even though no one is perceiving it any longer? If I am a Realist, I want to say 'obviously yes', but by what reliable method can I sensibly believe that? If Empiricism is true, my only reliable sources of belief about the world outside of my mind are sense perception and inference. I have never observed that the laptop exists unperceived, like I have observed that it is rectangular. So I cannot sensibly believe this on the basis of sense perception. But now we are back to the problem which is set up by the veil. That is, now I need some means of inferring that the laptop exists when unperceived; an inference starting with the data that I do observe. The problem of inferring mind-independent objects from the data we observe reappears, but this time we haven't presupposed a veil of perception.

Thanks to both of you for your replies.
PA

Thanks for thoughtful replies

T Clark, I take it that you aren't so interested in Scepticism in any of the forms that I described in my OP? You draw a contrast between "big S Scepticism" and "small s scepticism" where the first, I suppose, is one of the forms of Scepticism I outlined in the OP (or all of them?).

A person is Small s Sceptical about a proposition, P, if and only if either (1) they do not believe that P and think it does not matter whether or not P, or (2) They do not believe that P, they do think it matters whether or not P, but there is 'nothing they can do about it'.

It would be good to get clear on some of this if you wouldn't mind. What is meant by there being 'nothing you can do about it'? Does it mean 'nothing you can do to make it true or false that P'? For example, I can act so as to make it true that I am eating an apple, or I can act so as to make it false. But in the case of Descartes being a Frenchman, there is nothing I can do to make it false that he was a Frenchman. Is that what you had in mind? Or did you mean 'nothing you can do about it' in the sense of there being no important implications for your actions whether or not P. For instance, it makes no difference to how I act whether or not Descartes was a Frenchman. These are just my two guesses. Perhaps you meant something else.

On the topic of Big S Scepticism, I am not sure what you meant by that at all. Like I said, it would have been taken to mean any one of the types of Scepticism which I outlined in the OP, but you didn't say which; or it could be taken to mean all of them. What you did say about Big S Scepticism is that you think:

that's a luxury for people whose problems all fall into categories C, D, and F. — T Clark

Big S Scepticism about P, then, is an issue which arises if and only if (1) you believe that P, it matters whether or not P, but there is nothing you can do about it, or (2) you don't believe P and it doesn't matter whether or not P, or (3) You don't believe that P, it does matter whether or not P, but there is nothing you can do about it. The troublesome phrase enters here again, 'nothing you can do about it', but that aside, if Big S Scepticism only arises in these conditions, I am not sure it is any of the types I outlined in the OP. Just one example, my last kind of scepticism which arises for Realism when combined with Empiricism. If its true that no one has ever observed the property of unperceived existence, and it can't be inferred from things which can be observed, it will turn out that we have no reliable means of establishing Realism at all. It would be a mere guess, akin to if I were take a stab in the dark at how many blades of grass are in Birmingham city centre. That issue doesn't seem to presuppose (1), (2) or (3). It might be an issue only if I believe Realism, but I'm not sure of the relevance of the other conditions. I think this same kind of thing can be said about all of the other kinds I sketched, which leaves me unsure what Big S Scepticism is, as you understand it.

Charleton, I doubt that its useful to argue over 'what scepticism is'. Philosophers often refer to 'the' problem of scepticism, but I doubt there is such a thing. As my OP illustrates, philosophers have discussed quite different things under the label 'scepticism' and for quite different purposes. You quote my summary of ancient scepticism and write that:

This is not skepticism, this is apathy. — charleton

But this was what scepticism was for the ancients, and certainly for Sextus.

Your substantive remarks were:

Skepticism is the ability to reject the endemic assumption, reject the easy answer, and to examine the question a fresh. Ataraxia is not the end result of skepticism.
Freedom from dogma is the reward of skepticism, but this also goes with potential uncertainty as so often skepticism leads to never allowing yourself the luxury of knowing.

Scepticism as you understand it is an ability, much like for the ancients. For you it is the ability to reject 'the endemic assumption and examine the question a fresh'. Again, I think you are much closer to ancient scepticism than your initial remarks suggest, since this is just what they did. I do agree with you that you can't get Ataraxia through this kind of thing, but you can get freedom from dogma.

Wayfarer, Sextus, at least, idolizes Pyrrho as the originator of scepticism. As I understand it, the Pyrrhonian school was a splinter of the Academy. The Academy immediately after Plato held that nothing could be known and, even more radically, that nothing was any more plausible than anything else. The early leaders of that school, Arcesilaus and Carneades were thought to be capable of arguing equally well on either side of any question, and they frequently did just that in public. They had both also been heavily critical of the Stoics, who had originally held both that some things could be known for certain and that some things were more plausible than others, and supplied a criterion for this. The later Academics interpreted Carneades less sceptically, and this lead to a weakening of the doctrine and to the acceptance that some things were more plausible than others. Aenesidemus and a number of others are thought to have dissented from the weakening, and split off, taking Pyrrho as their hero, and embracing an even more radical scepticism than even the early Academy. All this, if you believe the account in Bailey's 'Sextus Empiricus and Pyrrhonian Scepticism'.

Pyrrhonism’s main tenet was ‘the cessation of judgement concerning what is not evident’. — Wayfarer

But then, Sextus' account of what 'the evident' is amounts to the beliefs, traditions, laws and customs of the society in which he belongs. About these, Sextus will not suspend judgement, but this is only because he has to live his life and cannot do so in complete suspension; a criticism which was pressed by the Stoics and Aristotle and just about everybody! But, although Sextus will not suspend judgement on those things, he denies that he accepts them in the same sense that dogmatists do. He just 'goes along with' these things for the sake of life, without making any claim to their absolute truth. I am not sure what you would make of this interpretation of Sextus, but it seems to me right.

You also drew some parallels between forms of Buddhism and ancient scepticism and I think you are spot on about that. Most thinkers have lost that element of scepticism these days. See Charleton above, as a case in point. I tend to agree with him/her that you can't get the kind of peace of mind those Buddhists and sceptics thought you could get from the 'don't know attitude', but I have found that the freedom from dogma that comes with the attitude does, at least, lessen my anxiety about certain topics, to wit, religion, morality and politics.

I think the value of scepticism lies in challenging what we take for granted. I think the inherent trust that modern culture places in naturalism is something certainly deserving of scepticism. But it's difficult to be sceptical about it, because the alternatives to naturalism have generally been dissolved by the 'acid of modernity'. The most common response is really a kind of nihilism - nothing really matters, and that doesn't really matter. And also the sense that the individual is the arbiter of what's real or important. There's a great deal to be sceptical about in this context, but it takes some careful analysis to understand how to go about it. — Wayfarer

I largely agree with this. Naturalism has far too easy a time these days, with few sceptical challengers. Your acid metaphor is apt, since what tends to happen these days is alternatives to Naturalism are scoffed at and treated as absurd. I cannot count the number of articles I have read in which Idealism is dismissed as unbelievable, incredible, 'dead', or just plain silly. Theism gets a similar treatment, though to a lesser degree because it has been defended as of late by some capable philosophers. What tends to happen with Naturalism is that anyone who dares raise a challenge to it is insulted and discredited ad hominem. Thomas Nagel is an excellent philosopher, and there are few who would deny it. But his book 'Mind and Cosmos' puts principle tenets of Naturalism under serious pressure and for that he got a number of reviews with remarks like 'what has gotten into Thomas Nagel?', 'irresponsible', 'ignorant of science' and 'dangerous to children'. This, together with the vagueness of Naturalism itself, make challenges to it difficult.

Hello,

I'm PossibleAaran. I was a member of PhilosophyForums two years ago. The site got new management around the time that I left. I went back to the old site today to find it completely broken. After digging around I found that the old guard had moved here.

I'm a PhD student in Philosophy and teach part time. I'm doing research on External World Realism and Skepticism. I'm also an amateur illustrator.

Nice to meet anyone I haven't met or doesn't remember me.