I think that we're trying to get at the same thing, here. The way I read you at least.

The OP argues against various positions, but never argues for theirs.

I mean... if we're going to rely upon scientific fact alone then why not?

There's certainly more being imported into assertions here than mere scientific fact. The similarity isn't completely out there. But if we believe in more than mere facts, like most people, then.... maybe it is. But it is also not quite right to then claim that you're being "purely scientific" or "biological"

if one accepts our premise that abortion is murder. — Thorongil

That there is the clincher, though.

Still not sure @LostThomist what makes you believe that conception is important. The best guesses I can make, based on what I've heard people say before, are not good criteria for human life. Usually when someone tries to argue that conception is biologically speaking human life they do so because the cell has a unique set of chromosomes -- the DNA which will proliferate throughout their body after said body has developed.

But I sincerely doubt that the mere presence of a unique strand of DNA is enough to qualify anything as life. DNA, after all, can and has been synthesized, one amino acid at a time. We do not think of these products as life, period, much less human life.

Potentiality is another criteria often brought up. But potentiality belongs to the gametes as much as the zygote. Is the menstrual cycle murder? I think not. Nocturnal emission? No.

Further, if we are relying upon biology I'd say we're actually looking at the problem from the wrong angle. Biology is the study of life as a whole. It's definition of life is largely differentiating what is alive from what is inanimate. It's not really looking at what is alive vs. what is dead. It's looking at species and ecologies, not individuals.

Also, if we're strictly scientific, there is no moral property you can ascertain from scientific observation. An individual does not become morally worthy at some point because it is alive in the eyes of science. So while we may reference this or that fact we will, very obviously, also have to introduce some sort of moral criteria and not pass our argument off as somehow scientific.

Lastly, given all that, I think the conception of time which this argument generally presupposes is entirely off. Organisms are alive in a continuum. They need to meet many criteria before they are definitively so, or before they are definitely dead. There are no necessary or sufficient conditions which are clear cut -- and certainly no singular event or point along the timeline of an individual life where something becomes morally worthy or not. The closest we might come to defining death comes from the medical field, but it's a bit hazy too. Life? There really just isn't a good point to pick where something becomes important, and before which it is not because the facts of the matter -- how life works -- doesn't easily fit into our desired legal framework.

The point of mentioning the metaphysical argument for biologically human life beginning at conception is to disprove any future argument which denies the humanity as a basis for abortion being moral.

Then.....I go on to argue against those who separate biological humanness from personhood — LostThomist

I use the word "magically" somewhat sarcastically........but what I mean by that is that...........the other places to use as the starting point for life would make it seem like a baby just popped into existence, whereas with conception you can see how it came about and thus proves itself more valid as an explanation.

Differentiating "hand waving" as an explanation for things from being able to show the causality — LostThomist

Wouldn't the zygote have to be a human life in order for it to be considered human life, though?

What about conception makes that point preferable and not "hand waving" to be human life and better than other points?

There isn't much significant difference, from my perspective, before and after. In fact I don't think you're likely to find any one point where there is going to be a significant difference, before and after.

Especially if you're just talking about biological life, from a scientific perspective.

it is philosophically impossible to claim that any group after conception is less than metaphysically human.

THEREFORE: Biological Human life begins at conceptions the same as all other mammals — LostThomist

How does you first premise connect to your second one? You begin by saying

For the purpose of a clear argument I will (for the time being) separate being biologically human from any concept of personhood. In doing so it is undeniable to say that biological human life begins at conception. — LostThomist

And then move into your metaphysical argument. But the metaphysical argument isn't connected to this beginning or your end. It doesn't argue that biological human life begins at conception.

The sperm and egg alone cannot grow a fully functional human body with free will. It is not until the sperm and egg meet that a substantial change happens and a human life begins. There is no other point in the development of the human body after conception that can be proven as the substantial change other than conception itself. — LostThomist

And, furthermore, you beg the question here by saying conception is the substantial change that happens where human life begins, even within your metaphysical argument. You go on to posit other possible places or reasons in order to argue against them -- but you don't argue for this.

Importantly: The sperm and the egg cannot grow a fully functional human body (not sure what free will has to do with this) without the mother. That's just a fact. It's not like conception is any more magical than any of the other points which you argue against.

I'd say that none of them magically make a human being -- that there simply is no point along the chain of events that magically makes a human being human.

Oi. That had to have been purposely ambiguous. So you could grade harsher on some and easier on others.

This is my point exactly. Showing that something exists unperceived and such that others can perceive it settles the interesting issue. If a philosopher continues to ask "ah but am I dreaming it?", I don't really know what he wants. — PossibleAaran

Well what if I park the car in the garage, and then ask you to go check to see if it is there. I'll give you a walkee talkee. I don't perceive the car in the garage, but you tell me that it's there. Isn't that just as good in that case?

Yes, I have read Quine. Why do you mention that?

It just struck me that some of what you were saying sounded like what he called Plato's beard. But maybe I'm off here.

Just a side note in the convo: I remember SR being treated as a minor point to GR in my physics class. SR was the sort of thing which we learned to do in order to be able to accept GR, or understand it. We, however, did not delve into GR since it required mathematics beyond what the SR class required. I only mention this because my take away was that SR wasn't meant to be taken ontologically (from a scientific realist perspective), only GR was -- in some sense GR reduced to or was "in line" with SR. I wish I could say more than that but alas I was a chemist (interested in philosophy, I hope thats obvious) and not a physicist.

I started a thread to explore being/having some time ago, but my mind got stuck. While I felt like I had the gist of the distinction, where I was stuck was with notions of character orientation, modes of being, and so forth. I'm still stuck there now, else I would have replied to my own thread by now :D.

A bit late but I do want to say I didn't want to "out" you in speaking to Banno. I have liked his exchanges with you because it's helped me get a better grasp of your philosophical orientation -- and, even if it may be frustrating for you -- I enjoy that fact.

I do not think of you as "outsider"; just thought that was worth mentioning with some of your posts I read here.

In my mind, at least -- not to contradict you, but simply to lay out how I think of these terms now -- I think of the terms in a kind of hierarchy where the first I mention is more "primary" to the last: being, existence, reality. But I know that I think of being in other terms than you do since I do not unite my thoughts on being with ourselves as humans. And maybe it is just a way of using words, too -- we may use different words for the same things. I tend to think of the way humans experience the world in terms of reality. Existence includes all logical propositions and propositions of mere reason. Being is the sort of term which underlies everything because everything, all named things whatsoever, "participate" in being. It's the sort of term which all names are a part of, and since it is so close to us (in that manner), it is hard to distinguish.

I should be able to eventually. My local library has access to a lot of academic journals. It'll just take some time since, like, I have to actually go there and stuff. :D

Cool.

I've said my piece about space. — Thorongil

Where?

Does it mean that it is a posteriori if we have to "probe the shape of space" for it? — Agustino

No. Just as placing dots on a paper to demonstrate counting or addition, or drawing a triangle to demonstrate a triangle do not make mathematical knowledge a posteriori, so too with light. In terms of the intuition it is no different from using a ruler.

Although I disagree it would be necessary. Again - Euclid's 5th postulate contradicts non-Euclidean geometries by not allowing cases that non-Euclidean geometry does allow. — Agustino

So? How does that have anything to do with the modality of the copula, in Kant's logic?

Therefore, it cannot be necessary. So why was it that we thought it necessary in the first place? How is such a mistake at all possible (to use Kant's transcendental language :P )?

I think your use of "necessary" differs from Kant's use. Even in the introduction you quoted Kant downplays necessity stating that universality was the more impressive proof -- that necessity follows from universality. I agree that he links the two there, but if we're talking about "saving" the Kantian system then I don't think we'd have to hold that link. Though maybe so. It's been awhile since I've read the text, so I'm not sure.

Your saying "necessary" means not mistaken -- or, perhaps more strongly, not even possible to be mistaken. I am saying "necessary" means to give assent to by everyone, and hence be objective.

Another one. Apparently, geometrical principles are united with the consciousness of their necessity - I don't see how that is the case with Euclid's 5th postulate. If we had the consciousness of its necessity, then we couldn't be wrong, could we? — Agustino

Yes, we could.

That consciousness cannot just vanish can it?

Yes, it can.

So my prior question remains significant - how is it even possible to be mistaken about our a priori cognition as it relates to our pure intuition? This cognition is necessary, if it is necessary, then we cannot be mistaken about it - that seems to follow, necessarily, if I may say so.

This is why I think you're harboring some Cartesian sympathies here. It's like "necessary" and "certain" mean the same thing to you -- if some proposition is necessary then it is not possible for it to be false. But truth and falsity have nothing to do with necessity, in Kant'. Truth is when some concept matches its object. Necessity is about the quality some judgment has -- so we judge a proposition as necessary when it is objective, i.e., it holds for everyone.

I mean, of course these things can change in Kant's system -- especially considering that necessity, being a category, isn't even time-dependent. What happens in time can change when some proposition is necessary.

So then this is just about categorising statements, not about how things really are? — Agustino

That's what I was doing in that exchange, yes. I was categorizing statements.

I've asked this before, but for completeness sake, I'll ask it again to the above: how can we be wrong about judgements which are universal and necessary? — Agustino

They turn out to be false. It's something of a cheeky answer, but really I don't think it goes much more in depth than that. Some people claimed to square the triangle, in ages past. That was false too.

Euclid's 5th postulate precludes forms of geometry that are actually possible in non-Euclidean geometry. Thus the two must be contradictory. If one is true, then the other cannot be true, except, maybe, in a limited situation. — Agustino

Maybe we are dealing with a limited situation in this case. So both can be true, if not necessary and universal.

However, I wanted you to explain how this works according to Kant. — Agustino

He doesn't really go into psychology very much. But mathematics seems to form the heart of his philosophy of science. So it would just be the fact that it's not a science, that we can be wrong, and so forth. It's a mundane answer, but I don't think there is a deep answer. Kant's dealing with the structure of the mind, a structure we all share as compared to the contrast class of an intellectual intuition. It's not really about our subjectivity as much, though Kant uses the word "subjective" in his own way that fits within the philosophy.

The self and subjectivity and all of that just aren't really there to be talked about. And psychology and anthropology are only mentioned in passing.

My original point was that space and time are the pure forms of intuition and are not themselves empirical, for Kant (and I think I remember reading you agreeing with this somewhere in this thread); whereas spacetime is an empirical model that predicts what will be observed. On that basis I can't see how, in the context of Kant's philosophy, the two can be thought to be the same. — Janus

Yup, I agree with your reading of Kant. I hadn't thought of your argument though. I suppose I missed your point, originally, but I think I understand you now.

I think the tendency is to think of them in conflict because of the universal nature of space, and how we come to know about space through Euclidean geometry. That's what I was thinking, at least. It's universal and so either one or the other must apply.

But now I'm sort of wondering if Euclid, though it was one of Kant's primary examples of synthetic a priori knowledge, could be taken as just that -- an example. And perhaps both Euclidean space and non-Euclidean space could be thought to apply universally. That is, any geometry could count as knowledge, even universally, insofar that we are at least applying it to the form of intuition (so that it's not just analytic and true by definition, but true by virtue of a concept matching its object).


I'd be hesitant to say spacetime just doesn't apply. But I hear you when you are saying that because it is an empirical model it simply wouldn't be the space that Kant is talking about. That makes perfect sense to me.

What do you make of non-Euclidean geometry? Let's leave spacetime out of it entirely, and just focus on the mathematics. Do you think only one kind of geometry could hold universally for space?

Geometric statements are a priori synthetic. We appeal to the form of intuition, such as when we place dots on a sheet of paper, look at our fingers, or draw a triangle. There is no particular existent to which we appeal, this is true. But our intuition is involved, which is why it can be called knowledge in the first place -- it deals with cognition.

We determine if a proposition is a priori if it is universal and necessary. Universality applies across all space and time. Necessity is a category which modifies the copula in the logic. It is a modal category which deals with how we assent to some statement. Those three categories are problematic, assertoric, or necessary. Necessity does deal with certainty. But certainty is holding-to-be-true for everyone, i.e., objective. That's the meaning of certainty in Kant -- it's more about intersubjective agreement, and our attitude towards a proposition than anything else.

So, in Kant's time the propositions of Euclid were universal and necessary, hence a priori. Furthermore, the subject and the predicate of those axioms were synthetic in that the predicate was not contained within the subject.

Now, we may be able to still say they are universal and necessary, which is the idea I'm sort of toying with. But my original thought was that since we have non-Euclidean geometry which is universal, and now know that Euclidean geometry is not universal because of that, then Euclidean geometry would not have the sufficient conditions for being a priori -- it would still be necessary, but not universal. And we would know that because we have a geometry to compare it to which is universal.

The first approximated the second geometry.

Since they were so close we simply missed it. Plus, we developed other means of probing the shape of space which were not available in Kant's time -- without which we wouldn't have noticed the difference.

This doesn't make sense. Either the geometry is a synthetic a priori, or it's not. It cannot merely "count" as a synthetic a priori at one point, and not at another. If it is a priori, then it is always a priori. — Agustino

Yes, true. I just mean how we categorize something, not what it is.

We can, on the other hand, be mistaken about which geometry is the a priori geometry. And if we can be mistaken, I have to ask that you specify how we can know if we are mistaken about it. And the further question, how can we know that (the geometry we have) it is a priori? Because knowing that, would seem to require infinite time, since a particular geometry (like the Euclidean) can always prove in the future not to have been complete.

Well, it's a priori because it does not rely upon particular experience -- it is non-empirical. Space itself is classified as non-empirical. We don't come to know it through inference. Space, like time, is unique in this way: that it is both part of our intuition, and that it is non-empirical.

So it would seem to me that any geometry should at least count as a priori simply because it's not something we come to by way of inferring from experience but is seated in the understanding, first.

What then makes it synthetic is that the propositions of geometry rely upon more than the principle of non-contradiction. There is something added to the subject. And how we do that, as humans, is through the understanding being used to judge our form of intuition (in the case of geometric propositions, that is)

What makes it knowledge is that we then compare our propositions generated in the understanding to the form of intuition. And since it is knowledge of the form of intuition it is also universal and necessary.

And it's that fact that the very form of our intuition is what we are coming to know which then guarantees certainty of how objects relate to one another and also how they react. Since it is the form of our intuition that we are learning about it applies to everything within that form. Hence we can also be certain of our knowledge.


Whether some set of propositions is incomplete doesn't really influence whether or not it is a priori. And it is fair to say that Euclidean geometry is an approximation of space, if we are to take non-Euclidean geometry as the sort of true representation of space. Newtonian mechanics, after all, still work within certain parameters -- we just weren't always aware of what those parameters were.

This doesn't make much sense to me. Both geometries are contradictory to each other. Two contradictory statements cannot both be true, hence they cannot both be a priori, since a priori truths are necessary, and hence always true. — Agustino

What is contradictory in them? Perhaps we are wrong in thinking that.

Propositions may be truth-apt, but if something is true in an a priori fashion, then it follows that it cannot fail to be true, regardless of what happens in the world. Like "it is raining or it is not raining". — Agustino

I think you're conflating a priori with analyticity here. The principle of non-contradiction is the hallmark criteria, for Kant, of analyticity. a priori just means without experience. All analytic statements are a priori, but not all a priori statements are analytic (according to Kant).

Why? Why does the fact that physics "rests" (what does that even mean?) on it guarantee it certainty? — Agustino

Because mathematical knowledge and scientific knowledge are closely tied together. And isn't a guarantee just another way of expressing that we are certain?

Apodeictic certainty just means that a proposition must be true to the consciousness who holds it to be true.

So if we have one kind of geometry which predicts physical phenomena then we have a reason for holding that it must be true. It is universal and necessary.

In fact, if we have two kinds of geometry, and one geometry does a reasonably good job of predicting some phenomena, but the other geometry predicts all phenomena then we know which one is universal and necessary, and which one is merely necessary (and therefore empirical, i.e., not a priori).

It's not that math and physics are identical to one another, but it is our knowledge of math which guarantees the physics. If it turns out that our physics needs different maths then we were merely approximating in our first estimations the form of the intuition.

Can you explain how you can be wrong about your own subjectivity, and what you mean by that idea? — Agustino

What exactly are you after here?

I mean, it doesn't strike me as controversial at all. Especially at the level of abstraction that Kant is working at. To use your question later on -- why was Aristotle wrong about the categories? Why did it take so long for someone to formulate the critical philosophy and identify transcendental errors?

It's because we're stupid, on the whole. Humanity can perform feats of intellectual might which are very impressive. But, generally speaking, we aren't all that smart and we make mistakes and we believe false things all the time.

I doubt this. Kant does talk about apodeictic certainty innumerable times with regards to mathematics. Part of the TA project, as far as I see it, is to secure where the certainty of mathematics comes from - and for Kant, it comes from the (synthetic) a priority of its propositions. — Agustino

Yes he does but it doesn't mean the same thing, exactly, either. Mathematical propositions must be true -- therefore they are certain. There is no more to it than that.

What exactly is the relationship between the intuition and the understanding that causes us to be capable of forming wrong concepts based on the former? — Agustino

Why on earth would it not be possible to be wrong?

The relationship, as I see it, is one of flow. I see the understanding as flowing down and the intuition as flowing up. In the middle is the schemata, which connects the two different parts of the mind -- kind of like a baptism of the categories into the forms of intuition. The categories are distinct still, of course, it is only the schemata which is the union between the two.

It seems to me that we can be wrong about all manner of things, though. And in this case, with geometry, if the two geometries appear very similar within the world as we are presently living in it then there simply wouldn't be a reason to think there is another one. But then we lived in a different way and someone had some ideas and it turned out to be that we were wrong in some of our predictions.

Why exactly do you think we can't be wrong? Simply because the knowledge is universal and necessary?

In Kant's time, Euclidean geometry was both of those things. It wasn't until we developed different physics, different geometries, that Euclidean geometry -- as the mathematical model of physics (plus other maths, while we're at it) -- were seen to be approximations.

So, if space is transcendentally ideal, then there is no noumenal space, correct? — Agustino

Of the noumenal world nothing is known, period. So the proposition "The noumenal world is lacking space", while truth-apt, cannot be judged. There is no basis upon which such a judgment can rest. The noumenal world may have space, it may not. We simply do not know nor can we judge in either direction. To believe something along those lines would be to be doing metaphysics, which our understanding is incapable of turning into a science.

So why is it that it took so long for us to discover non-Euclidean geometry? — Agustino

Sort of a repeat question again, but why shouldn't it take us so long to discover non-Euclidean geometry?

It seems to me, paired with your balking about being wrong about subjectivity, that you're harboring some Cartesian sympathies for knowledge of the self.

That's fine and all, but if we're talking about Kantian philosophy then the self is not so central in his philosophy. Subjectivity is. But knowledge of the self is not given priority. It is not more certain. In fact, the most certain knowledge in Kantian philosophy is of mathematics and physics, and not psychology :D. (Kant didn't even think chemistry was a science proper.)

Also: certainty is definitely not as central in Kant's philosophy as it is in Descartes'.

According to this development of Kant, we gain knowledge by comparing our concepts with our intuition. Do you claim that, in our intuition, we knew that non-Euclidean geometry is possible? If we did, then why did it take so long for us to compare our concepts (Euclidean geometry) with our intuition, and find out that they were different?

I don't think the intuition knows anything. Knowledge is not generated without both parts of the mind.

They are very neat. :) I can't deny their sway.

I also admire your continued parlay with apo. Not that I'd do it in the same way, or even agree with your arguments -- but simply the fact that you continue to argue. It's actually helped me to understand apo a bit more; not just your commentary but also apo's responses. Something I didn't have the patience for, but really should (philosophically speaking).

The SEP has an article specific to transcendental arguments, as well. I enjoyed reading it.

Wikipedia is still good for a general introduction that's fast to read, though. Just thought I'd note it. (I'm enjoying your exchange w. Janus)

There is no contradiction. Is Descartes contradicting himself in holding that although he might be mistaken about whether there is really a tree because he might be dreaming, but he cannot be mistaken about whether it seems that there is a tree? I hold the same view but put it differently. His 'seeming tree' is my 'tree'. I cannot be mistaken about whether there is a tree, since, even when I am dreaming, I am directly aware of a tree. I could be mistaken about whether the tree I am aware of is a dream tree or a real tree. I then have an explication of the difference between 'real' and 'dream'. — PossibleAaran

If not a contradiction then at least some linguistic cleaning would be nice from my perspective.

Descartes cannot be mistaken whether it seems like he is seeing a tree. Precisely because "seems" modifies the statement: You cannot be mistaken about whether it seems there is a tree, but you can be mistaken about whether there is a tree -- even when you a dreaming.

I think that it's a little sloppy to split "tree" into types -- it's not like "dream tree" and "real tree" are species of the genus "tree". "Real" does not work exactly in that way. Even when it comes to a logical display of these terms it's not a matter of kinds and categories, but is an operator which ranges over a domain -- some set.

Just curious -- have you read Quine's On What there Is?

You say you can't give any definition of "real". That isn't necessarily a problem, but tell me this. Supoose in your dreams last night you saw a dream tree (or seemed to see a tree, if you prefer). It was 200ft tall and had large purple leaves with different animals on every branch. You wake up and go to see some friends. To your surprise, one of them starts telling you about this dream they had. They dreampt about a tree 200ft tall with large purple leaves! Another friend pipes up and begins to describe animals that were in the tree, exactly as you remember it. A last friend, getting very excited, explains that he dreampt the tree too, and he describes faithfully the buildings that surrounded the tree.

Over the next several days each of you dreams about the same tree again, each time sharing the same story with one another. If this happened, would you still insist that the tree which all of you keep dreaming about isn't a "real" tree? What would be the meaning of that?

Probably not. It wouldn't quite fit into my conception of dream anymore, though, either. I'd be uncertain exactly how to classify it, but if such phenomena were common -- or if I even experienced it just once -- I'd probably hesitate to use dreams as a contrast class to reality.

But if physical effects external to ourselves can be shown to influence the geometry of space, is this not fatal to the assumption that space is an a priori form of our intuition? — Perplexed

I don't think so. Specifically because since the physical effects are demonstrated then they already fall within the form of intuition. "outside us" is not something that relies upon our intuitive perception of space, but rather "outside" -- meaning the noumenal world -- is outside of all possible knowledge. If we demonstrate that space behaves in accordance with one or another geometry then I'm inclined to say either 1) we have determined the "correct" geometry which conforms with the intuition, or 2) that both geometries are "checked against" the form of intuition, and hence both count as knowledge.

I still don't have a lot of time, so since you think this might be the salient point of our disagreement, we probably should focus on defining our terms and thereby hopefully gaining enough confluence to progress the discussion.

"Thoughts without content are empty, intuitions without concepts are blind." This well-worn quotation form Kant I have always taken to be suitably paraphrased as " Conceptions without perceptual content are empty, perceptions without conceptual content are blind". — Janus

No worries about time. As you see I can take a bit of time to respond too. (sometimes too much time! Sometimes I run out of ideas, too...) Take as much time as you need.

I don't think your paraphrase is off. I also don't think the well-worn quotation is Kant at his most rigorous. I think perception is a good stepping-stone for getting a handle on the critical philosophy, but when speaking strictly I'd caution against thinking of intuition as perception. Intuition is just one half of the mind which acts entirely differently from the other half of the mind -- the understanding.

Or, another way of putting this would be to say there's the understanding and sensibility, and intuition is a part of sensibility. I'm not sure which way to put it, myself.

In either rendition though perception is a psychological phenomena -- it deals with how a particular mind, and how many similarly wired particular minds, come(s) to recognize some phenomena as that phenomena.

But in the case of Kant we're dealing more with how all particular minds arranged Kant-wise (just to be cheeky -- I forget the exact term Kant uses, but our minds are contrasted with an intellectual intuition to give an idea of what sorts of mind he means {EDIT: and, just in case, an intellectual intuition is something like the mind of god, where thinking something creates reality -- not trying to talk down, just trying to make sure I cover my bases}) come to have knowledge about the world -- and in particular synthetic a priori knowledge. It's not about how we see a particular phenomena as that phenomena, but rather how it is possible for us to know some subject is attached to a predicate synthetically and without having to rely upon particular experience.

Linguistically -- perception's "link" is the word "as", and knowledge's "link" is the copula.

Oi. Well, the questions got specific enough that I felt a need to review. So far I've just been relying upon memory, which is far from faultless but a hell of a lot quicker when it comes to responding. :D

Thus far I've read these two articles to remind me of the finer points of the aesthetic -- though I am fine with cracking open the source material too if we need to. Regardless, these are both pretty darn good articles to read with respect to the original question:

https://plato.stanford.edu/entries/kant-mathematics/
https://plato.stanford.edu/entries/kant-spacetime/

@Janus and @Perplexed too for the above articles, though the rest of this is directed at Agustino.

On what grounds do we judge a geometrical proposition to be a synthetic a priori? — Agustino

After reading the above articles I might make a modification, actually. I'm sort of toying between two ideas. Originally my thought was that any geometry upon which natural phenomena are predicted would count as the synthetic a priori geometry, whereas previous geometries would be considered approximations of the a priori -- and therefore empirical, since they are no longer necessary (at least for predicting physical phenomena occuring within the forms of space and time).

But now I'm wondering if it's possible that both could be considered synthetic a priori -- since we can demonstrate either geometry within the non-empirical intuition by means of either physics. It would still count as a cognition regardless of the physics we use.

(1) Why is it sensible that we could be wrong about the form of the intuition?

"Sensible" as in why does it make sense and is reasonable?

If so, then it would just be a matter of the fact that propositions are truth-apt. We can say "All intuitions are empirical", and that would be false (via Kant, at least). There is a subject, "is", and a predicate, and the category of "Allness" appended so it fits within the logic of Kant. And surely it is truth-apt, since Kant argues against the truth of the proposition.

(2) Does the form of intuition belong to our subjectivity? If so, is it possible to be wrong about our own subjectivity?

Yes and yes.

"Subjectivity" understood within the context of Kantian philosophy, of course. Definitely a tricky word, but yes and yes.

(3) Can we know whether a geometric statement really is a synthetic a priori with certainty? And if so, how?

Well, toying with the two ideas I talked of above...

My first inclination was to say that any geometry upon which the physical sciences rests would count as the synthetic a priori geometry, and would thereby be certain.

But now I'd also note that certainty isn't quite as important in Kant as other epistemologies. Certainty is obtained subjectively or objectively -- and the difference between the two is subjective certainty is where one person holds something to be true, and objective certainty is when everyone does. I had to look up certainty in A Kant Dictionary to come up with that, though. It's by Howard Caygill, and just like the above articles certainly relies upon a certain interpretation to help readers through Kant -- but unfortunately I didn't mark in my CPR where Kant talks about the conditions of certainty :D. So I found it hard to find.

I don't follow how "we are able to have synthetic a priori knowledge about space due to our knowledge of geometry". Our synthetic a priori knowledge of space is what we codify through geometry.

I'd very much disagree with this assertion. Though space is the form of outer intuition, and is so for everyone with an intellect like ours, knowledge cannot be obtained except by the use of both our understanding and intuition. Space is an intuition, and knowledge of space only comes about by use of the understanding.

I also don't follow what you mean by "space isn't intuitively obvious to us". For example, it seems impossible to imagine 4D space. So is the three-dimensionality of space not something intuitively obvious to us? Could we be wrong about that too? And what would that even mean?

Eh, bit of a side issue, but I would say that 3D space is not intuitively obvious to us.

Regardless, though, "intuition" is not the same as "intuitive" -- "intuition" is one half of the mind which operates differently from understanding, where "intuitive" is more akin to meaning obvious or easily comprehended without instruction or something along those lines.

My main point here is that "intuition" does not mean the same thing as "intuitive", and that is an understandable mistake, but a mistake all the same.

If I follow you correctly, your point is the traditional Kantian one that the phenomenal world is organised through the a priori forms of space and time and the categories of the understanding - so in this specific case, space doesn't exist "out there", it is just how we represent the phenomenal world to ourselves. In other words, space continues to be transcendentally ideal per your view?

More or less, yes. Not sure about "out there" in your reply, so I say "more or less", but everything else is what I'd say (that Kant says, at least).

So if we don't have synthetic a priori knowledge of the form of intuition there are two main questions:

??? I don't mean to imply we have no synthetic a priori knowledge. Is it of the form of intuition? I'm not sure because things get funny when we are looking at the frame (is it knowledge, at that point? Or simply what we must accept in order that knowledge be possible? Is it really a cognition anymore?). But mathematical knowledge relies upon the form of intuition.

(1) Since the form of intuition is subjective, why don't we have such knowledge? How does acting in the world (empiricism, scientific experiments, etc.) help us gain that knowledge? Aren't we ultimately gaining knowledge about ourselves then?

We do have that knowledge. The way that acting in the world helps us gain the knowledge is that we compare concepts to our intuitions, and the form of intuition is the basis for geometry. In a way you could argue we are learning about ourselves, but in a way that also doesn't make sense to say -- because it's not really about our identity or psychology but rather the possibility of knowledge.

(2) How do we even know that synthetic a priori knowledge even exists if we do not know when we have it? How can we know if a piece of synthetic knowledge is a priori (Riemmann) or a posteriori (Euclidean)?

I think in the above I answered these. Let me know if you disagree.

Yeah, I admit that I'm uncertain about the actual reactions to the skeptical scenario. I'll say that it's an ideal solution, at least. One which, at least as I read you, seems to be where we are in agreement.

And there is definitely something to what you're saying -- that solutions are (often) co-morbid with pernicious intuitions. I tried to read the paper that the OP was referencing, but I couldn't find one that talked explicitly about anti-realism -- only the argument about how a BiV could not refer to itself within the BiV due to semantic externalism. But there's that dichotomy again -- internal/external -- which, being a solution, certainly lends support to what you're saying here.

Hrm hrm hrm. Not sure if I have much else to say. But thanks for sticking with the conversation. It's been interesting (not to cut things off -- by all means feel free to continue. I just wanted to give a faster reply, and I think I've run out of thoughts)

Not exactly... I don't think of it as a test for bullshit, or what can be discarded. Please forgive my lack of clarity and allow me to try again.

This actually ties into ancient skepticism, in a way. Ancient skeptics would use arguments in a medical capacity -- the goal was to help a student attain the appropriate attitude towards various philosophical theories, one where you neither assent nor deny their truth.

In that sense of an argument being judged for its medical usage -- or perhaps hygienic or pedagogical? Since I don't think the radical scenario is one that's needed for a cure, like the ancient skeptics, but does help one achieve a certain appropriate attitude -- I'd say that the skeptical scenario is a sort of hurdle which, once overcome, has a person thinking more clearly. The set of intuitions I listed are common enough, and often incorrect, that it makes sense to help guide someone interested in a philosophical view of things to be able to suspend said intuitions. Or, at the very least where that's not possible, be aware of them as unexamined beliefs held.

The majority of people who read Descartes do not end up "biting the bullet". Now they may just pass over it as a non-problem, which isn't exactly my goal either, but they at least don't fall all the way down the rabbits hole. I suppose there is an empirical element to this -- what are the common reactions to the radical skeptic scenario? How do people actually respond?

But ideally, from my view, overcoming the hurdle allows one to put to rest erroneous beliefs and unexamined intuitions which commonly structure our thought regardless -- and hence would rear its ugly head in examining other philosophical problems.

EDIT: Also, I think it a worthwhile part of any philosophical education to teach the skill of questioning and suspending your own priors. The skeptical scenario, being ridiculous and unacceptable, is a sort of hammer which, I hope at least, helps one recognize that ability to examine your own beliefs.

You don't disagree that my solution "works" then, though?

FREEMASONS!

If we're going to jump, then let's jump all the way in. :D

It's cool. Take as much time as you need. It does seem, based on what you've said to Agustino, that you prefer the first strategy I proposed. I prefer the 2nd, or at least some modification of the 2nd, since I still think about this stuff and am not settled on it. So we'll see where the conversation takes us.

Sorry for the delay. I had to have me a think after your last reply. i'm going to try and focus on in this reply to where I think our prime disagreement is -- the philosophical point (or lack thereof) of the skeptical scenario.

I think you're misreading me as a quietist, this isn't my intention. I'm interested in 'the skeptic' as a discursive role here. Hence all the references to the character of the skeptic and describing how the transformation between 'normal philosopher' and 'skeptic' is inherent in 'the skeptic' (and hence radical skepticism) as a philosophical construct. Still doing philosophy here. — fdrake

Cool. I think that helps me to understand more of where you're coming from.

It seems you agree that the only escape is to ironically disavow the judgemental whispers of our angry God. — fdrake

I don't really view responses to the skeptical scenario as one of escape. If the skeptic is wrong then there is nothing to escape from, after all. There are only a handful of inconsistent beliefs based on intuitions of interiority and exteriority, certainty and doubt, reality and appearance, and knowledge and opinion. I tried to line these all up in the same way to show how these four intuitions are structured along a similar axis -- interiority, certainty, reality, and knowledge on one side with exteriority, doubt, appearance, and opinion on the other. There may be others but these are the four intuitions that come to mind at the moment that the skeptical scenario plays off of. We know ourselves with more certainty than the external world. We have a "more imediate" connection to our interiority while we are distanced from and judge exteriority. I, at least, am real -- for I am a thinking thing, and in the moment of thinking "I am" I cannot doubt such a proposition.

In addition, we desire certainty. So the possibility of error plays off of this desire for certainty, stability, and control.

In some ways I view all of these intuitions as traps of thought which apply elsewhere. So I view the skeptical scenario not just as a play -- though I think your characterization has merit for understanding the discursive function of the skeptic, for sure -- but as a tool which takes commonly held intuitions and brings them to conclusions so absurd that they are not acceptable. (for most, at least) It's more a method of bringing someone to a reflexive position towards their own intuitions -- though, granted, it seems that we have seen examples of it doing the complete opposite, where someone doubles down on those intuitions and "bites the bullet" -- but I don't think that's the usual route, just the one you see because it's far more expressive and ridiculous.

It seems to me that by changing our intuitions and questioning our initial beliefs about knowledge that the skeptical scenario is avoided before it gets off the ground. But if we have such intuitions about knowledge, etc., then the skeptical scenario's philosophical point is that it puts those very intuitions into question.

Take the dream tree, does it exist? Well, if it doesn't exist then what is it that you are aware of when dreaming? Nothing? But it sure seems like you are aware of something doesn't it? Some qualities are there before your consciousness are they not? If I were to ask you about the dream tree, couldn't you tell me about it? You could tell me "it had a trunk 500 metres high and purple leaves", for example. If you told me that, you would be describing what you were aware of when you dreamt, and you couldn't do that if there were nothing you were aware of when you dreamt, could you? This is what leads me to insist that the dream tree does exist and that the only difference between it and a real tree is that a real tree can be perceived by others and exists unperceived also. In fact, I would go as far as to say that what I mean by "real tree" is " a tree that can be perceived by others and which exists even when no one is perceiving it". — PossibleAaran

Yes a dream seems like we are aware of something. I can tell you about my dream. I think that neither of these things make something real, though. This sort of reminds me of On What There Is, although we are talking more about awareness and seemings here than statements. The only thing I'd contend is that even though I am aware of dreams and I would even say I am justified in believing they are real because they seem real to me, that they are not real.

The difference between the dream-tree and the tree isn't that others can perceive it. I'd say that this mistakes the how for the what -- how we come to be justified in believing something exists differs from what that something is. Or, in this case, that it is at all. We come to believe something is real based upon what others say and do, and come to doubt something is real if others do not perceive what we perceive. These are the methods. But the methods don't define what it means to be real, only what it means for us to determine if something is real or no -- how we come to reasonably believe it to be so, not whether it is so.

Our perceptions aren't infallible. I can make mistakes in perception, as when I think that a tree is 'real' but it isn't. But what this mistake amounts to is that I thought the tree was such that it could be seen by others and existed even unperceived, and I was wrong on both counts. But, even when I was hallucinating, I couldn't be mistaken that I was seeing a tree - even if it turned out to be a mere hallucination tree. This is essentially Descartes' view that he cannot be mistaken that he seems to see a fire, even though an evil demon might trick him into thinking that there 'really is' a fire. I have just tried to explicate what I mean by 'real' and used this concept instead of Descartes' terminology, because I think his terminology encourages the veil of perception doctrine (I do not think that he actually espoused that doctrine, but his phrasing in an English translation makes it very tempting). Whether you mean the same thing by 'real' I am not sure. It would be interesting to find out what you do mean by 'real' if not my explication, and equally interesting to determine whether dream trees or ordinary trees are 'real' in your sense, and what bearing this would have on our present subject matter.

Hrmm... I think you're coming close to contradicting yourself here. Either our perceptions are infallible, in which case I cannot be mistaken when I see a fire, or they are fallible, and I can be mistaken when I see a fire.

I wouldn't define "real" in terms of perception, whether it be mine or others. I'd say that perception handily fits into our notions of rational justification, rather than what it takes for something to be real. So in the case of a dream or a hallucination I am not seeing what is real, but I believe that I am seeing what is real. That being the case it is equally reasonable to believe that, though I may be mistaken, the car I parked in the garage is still there. That's more or less the angle I'm going at -- that it is just as reasonable to believe that things continue to exist unperceived, because there is nothing special about perception when it comes to whether something is real or not, and if we have perceived something, at least, then we are just as justified in believing in its reality as if we are perceiving something.

I tend to think of the real as given. It is beyond belief. It contradicts desire and perception. In some ways it seems like it can't be countenanced -- that there isn't such a thing as a theory of the real which would tell us what it means to be. I like Quine's answer as well, but it seems a little too bound up in the language of propositions to me. It doesn't seem to me that reality is bound to propositions as much as it outstrips them (even though they remain true).

But beyond this notional metaphor of reality I could not honestly give you a hard philosophical answer to your question. I could only say what it is not, and why that fails, and hope that there is some common ground in there.

As far as I understand it "intuition" for Kant means something pretty close to what we would call 'perception'. — Janus

I disagree with this, but I'll touch on it in replying to your third paragraph. Probably gets to the crux of our disagreement though.

You say "we are able to have synethic a priori knowledge about space due to our knowledge of geometry" but if this were true then it would not be "synthetic a priori knowledge" at all but synthetic a posteriori knowledge. I think it is more to the point that we are able to have knowledge of geometry due to our synthetic a priori knowledge of space. I think that is certainly what Kant thought. — Janus

I don't disagree with that interpretation of Kant here. This is why I think non-Euclidean geometry is problematic, just not destructive to the aesthetic. It can be "saved", that is -- and still feel reasonable rather than ludicrous.

So, following my second strategy, Euclidean geometry could be interpreted as synthetic a posteriori knowledge while non-Euclidean geometry could be interpreted as syntehtic a priori -- and the same would apply to any other geometry which predicts the events of the phenomenal world.

I don't think it makes sense to say that Euclidean or non-Euclidean geometries are "wrong"; both are intuitively obvious in their contexts. This is not say that it is, or even can be, intuitively obvious that spacetime is curved, because, to repeat myself, I don't think we have any reason to think that spacetime is the same thing as perceptual space, for the simple reason that we cannot perceive, or even visualize, the curvature of spacetime. Is there any reason you can think of why we must believe they are the same? — Janus

It's not our perception of space that's at issue, I'd say. The propositions of geometry are closely tied to physics, by my reading. Because our intuition follows mathematical laws we are also able to apply those mathematical laws to objects, which are themselves within our intuition.

Strictly speaking it's not perception which intuition is trying to explain, but rather intuition is one half of the elements of cognition which explains how knowledge of objects is possible. Clearly there are relations between perception and cognition, and granted the intuition's description relies heavily upon visual imagery (like a lot of Western philosophy), but the reason why mathematical laws are able to be posited and discovered in the phenomenal world is because our cognition relies upon this form. It sort of explains why we are able to make predictions which are actually caused -- meaning the "necessary connection" between two events -- in the first place, rather than merely the constant conjunction of non-related events believed by force of habit.

So if it turns out that Euclidean geometry is not the form of intuition it would seem to upend the notion that we have synthetic a priori knowledge of the form of intuition. Same goes for the physics based upon that synthetic a priori knowledge. However, if Euclidean geometry were merely empirical, an approximation of our cognitive faculties as Newton was an approximation, then I'd say that the aesthetic is saved.

But in either case, it's not how we perceive that's at issue. It's how we are able to know math and why it applies to the objects of our perception in the first place. Kind of a hair-thin distinction, but I'd say it's important because in one case we are dealing with phenomenology and psychology, and in the other we are dealing with the possibility of knowledge which seems to fit more in line with the whole Critique.

OK, the problem I have now is with the notion that we experience space. Space is the pure form of intuition, according to Kant, which means that intuitions (visual perceptions in this case) must take spatial form, and our a priori apprehensions of that space are intuitively obvious to us. — Janus

I don't think "intuition" in Kant means the same thing as intuitive. Space isn't intuitively obvious to us. Others have been wrong about space -- like Leibniz and Newton, for instance. So while the examples Kant uses are from Euclidean geometry it seems to me that one could modify the philosophy without losing the core of the aesthetic. It's not that something is obvious, but rather that we are able to have synethic a priori knowledge about space due to our knowledge of geometry. If one geometry is wrong then, just like Newton could be wrong, we could understand such sciences as something which wasn't part of our cognitive faculties but was derived from them, and is therefore empirical in that sense (and not synthetic a priori knowledge, but instead rests upon that)

I'm having trouble making sense of the idea of Euclidean geometry as an "empirical concept", other than it being obviously a conceptual scheme derived directly from everyday experience (taken in its broadest sense of both "inner" and "outer" experience) — Janus

That's what I mean. Surely it's sensible that we could be wrong about the form of inuition. So, supposing non-Euclidean geometry is the true geometry of the space we experience it doesn't seem like a large step to say that we were simply wrong before about the form of intuition. At least not to me. If that were the case, then it would just be an empirical concept, though -- since a priori concepts of space are apodeictic.

I think it poses a problem, but I don't think it's devastating to his project. While Euclidean geometry and Newtonian physics are the backgrounds upon which he's clearly thinking from, neither are necessary.

One way of arguing is that our intuition is still Euclidean. So in spite of non-Euclidean geometry, our form is Euclidean.

Another way of arguing: you could say that our intuition of space is actually non-Euclidean (or whatever happens to be the correct geometry of space, supposing non-Euclidean geometry is superseded), and Euclidean geometry was merely an empirical concept of that form.

By "you" I meant you. As in, the person I'm having the conversation with.

Holding or studying JTB is neither necessary nor sufficient for responding to skepticism, the point I'm making is that skeptical scenarios are close conceptually to accounts of propositional knowledge, especially necessary/sufficient conditions for it. Propositions are the target of justifications, justifications are undermined through skeptical scenarios (can say the same about Gettier cases). You can vary what counts as an adequate justification, and in doing so attack the skeptic: eg. fallibilist justification sweeps the rug from under their feet, foundationalist justification under the guise of hinge propositions attempts to do the same; but it's still the same highly constrained and a-historical account of knowledge that makes sense as something for the skeptic to attack. Can radical doubts be formulated in the same way against, say, knowing how to ride a bike? Specifically, sufficient conditions for knowing how to ride a bike are competences - which don't always have propositional equivalents — fdrake

It's a good question. I think it may depend upon whether or not you'd consider riding a bike in the vat is the same as riding a bike outside of the vat. I wouldn't change the scenario (especially since I consider the radical scenario pretty much the same, rationally, just with different dressings). I just wonder if we could count these as competences or not.

Conceptual/contextual baggage of radical skeptical inquiry destroys the context in which knowledge arises, taking it to a bizarre intellectual limit in which paranoid delusions become respectable avenues of thought, lived life is condensed into a logical network of linked propositions; engaged with merely through assent and disbelief, and anything within the bounds of possibility masquerades as justified belief. — fdrake

Wouldn't any a priori investigation do the same?

Also, doesn't any investigation bring along conceptual or contextual baggage? There are, after all, only so many words to use. And philosophy has a long history.

Then what's the point in pretending to be the skeptic? Do we really carry a copy of a rebuttal for every skeptical scenario to allow knowledge to take place? — fdrake

Well, I don't think there is a point. And of course you don't carry a copy of a rebuttal for every skeptical scenario just to allow knowledge to take place. Simply by changing the definition of knowledge you're already talking about something elsewise from the skeptic.

I think many, if not all, philosophical puzzles are like this. There is no point to them -- they are fully and completely useless. But engaging in them is a good exercise of the intellect, and formulating responses are the same. And often what is useful is what comes out of such inquiries -- but the inquiries aren't bounded by the terms of use or purpose.

To give other examples, what is the point of of formulating the question of the meaning of being such that it becomes meaningful again? What is the point to formulating a general theory of justice? What's the point of understanding knowledge historically, as opposed to a-historically?

I think points, purposes, reasons, and so forth are found after the fact. Which is why philosophy is, paradoxically, uselessly useful. (at least, philosophy of this sort)


But as for points that I see -- it's a good exercise in a priori reasoning. It pries at commonly held intuitions by working off of them and coming to absurd conclusions. It's relatively straightforward and easy to communicate. It generates novel solutions to the problem of skepticism which are interesting unto themselves. In a way it is a propaedeutic to philosophy -- else you might have people claiming they are certain of this that or the other when they are only provisionally so. It also serves as a class example for all sorts of skeptical problems, and working through it rationally helps one to let go of the gut reaction to balk at what is, on its face, unreasonable.

Maybe it's a non-philosophical approach to skepticism. The skeptic and propositional knowledge are inseparably joined through the unilateral need for philosophically rigorous dismissal of the skeptic; the philosopher is pretending to be the skeptic through interlocution and the distinction between them dissolves in the process; only to be re-contextualised as an imagined enemy. The enemy only makes sense in the context of the theatre of skeptical arguments.

Seeing it as a philosopher's dramatisation of an imagined struggle - when reason reconciles itself with paranoid delusion - takes the sting out of it, no? — fdrake

Heh. I can see it doing so for some people. I suppose it would have to sting in the first place, though. :D I don't feel that sting as much precisely because I'm not a skeptic, and have formulated thoughts and responses to the scenario that were sufficient for myself.

And, on a rational level at least -- though belief in skeptical actualities probably doesn't take place at a rational level, that I'll grant -- it seems to me that whether the skeptical scenario is presented as a drama or no that the puzzle remains the same.

What is the difference between a merely dreamt tree and a real tree? I think the answer is two-fold. First, a real tree is a tree which can be perceived by other people, and second, a real tree is a tree which exists even when I am not aware of it. The tree that I see when dreaming cannot be seen by other people and exists only when I am seeing it. When I wake up, the dream tree no longer exists. — PossibleAaran

There are certainly differences, but I think that misses the point of the dream scenario. The point of the dream scenario, here, is to show that we can believe that what we percieve is real when, in fact, it is not.

So the dream-tree does not exist, even when I am seeing it. It is a dream. It doesn't pop in and out of existence. It never existed ever. Yet, upon my perception of it, I certainly believed it to be real.

So our perception of things is not infallible, at least, when it comes to determining if something exists or does not exist.

If you insist on the dream being real, then consider hallucinations, mirages, delusions, and so forth. Our perceptions are surely not infallible when it comes to determining if something is real or not.

This isn't to claim the part of a skeptic, but to point out that what you already accept as reliable is basically just as reliable as having seen something.

While an object is being perceived I am directly aware of it. When I am directly aware of P I am - to say the very least - in a good position to tell that P exists. When I am no longer perceiving P, how can I reliably tell that P is still there?

I'd say that if you have seen something you are aware of it. When I park a car in a garage and close the door I am aware that my car is in the garage. Something may have happened in the meantime. And I may have been dreaming. But because I have seen where I put my car I am in a good position to tell that it exists because I am aware of its existence.

Why on earth would we need to persuade the skeptic away from their infantile delusions and performative contradictions? The deck is stacked in their favour, they will destroy all knowledge (hypothetically) if you let them. — fdrake

Sure it is. Which is why it's an interesting puzzle to ponder. I wouldn't say need is the basis for wondering about persuasion. I would say we don't need to do philosophy, even, for that matter. Rather than necessity I think the motivation is one of curiosity.

The skeptic isn't a real person, no one acts as if knowledge is impossible, no one thinks that way either. The skeptic is a philosophical construct aligned with the mere possibilities of erroneous justification, and the mere possibilities of error in every belief. We should stop giving into this alternate personality every student of philosophy can adopt, salivating in response to improbable, unjustifiable fear of error which implicates all of reality in a personal conspiracy against them. — fdrake

I don't feel like I'm giving into anything. I feel like I have responses to the skeptical scenario. As I read you, at least, it seems that you do as well. But there aren't any factual -- at least, empirical -- grounds for refuting the skeptical scenario, based on exactly what that scenario entails; that the world as we experience it appears identical, yet is actually different. (Another distinction which one could attack the skeptical scenario on)

Attempting to find necessary and sufficient conditions for knowledge outside of the contexts knowledge arises in is a pointless exercise. If the examination of intuitions is the goal and sole reason to entertain 'the skeptic', why not look at how people come to knowledge in the real world? — fdrake

I don't think that the skeptical scenario is goal-bound. Philosophy isn't exactly goal-bounded, either. Being able to think through why you disagree with the skeptic is fruitful, though, in that it is a good exercise.

Also, oftentimes when we approach a question by looking at examples -- as often as I really do use this method -- the examples are overdetermined by our intuitions. So having thought puzzles to ply at those intuitions are useful to philosophical exercise.

Believing in the utility of skeptic thought experiments actually has real consequences for epistemology: for one, the skeptic (and the JTB enterprise it is coupled with) are entirely concerned with propositional knowledge. Secondly, they don't allow any incorporation of learning skills or learning facts to resultant knowledge-how and knowledge-that. And for three-the skeptical hypothesis is indifferent to how beliefs and competences form networks that allow people to act skilfully in the real world.

Far from analysing how people actually obtain knowledge; the corner of philosophical discourse devoted to the skeptic isn't even examining the conditions of possibility for knowledge - it's far too constrained for that. Dealing solely with propositions, hypothetical justifications and the mere possibility of error in belief. — fdrake

I don't disagree that the skeptical scenario has real consequences for one's epistemology. But I don't think dismissal is the exact right response, either. While we have no need to address the skeptic, while we can investigate knowledge otherwise I would also say that one is not devoted to JTB forms of knowledge just by way of responding to the skeptical scenario. Like, at all.

I mean, while I think examining what we believe knowledge to consist of is the best response to the skeptic, that doesn't mean we have to believe that knowledge is purely propositional. Why would it?

I don't think the skeptical scenario is foundational to epistemology -- which is maybe what you're against -- but I also don't see a reason to be dismissive of it. It seems to me that formulating a reasonable response, of whatever sort, is the proper philosophical route.

It is even an impoverished form of skepticism, the pyrrhonists at least espoused skepticism for a practical reason, and prescribe ataraxia as an appropriate response to the real lack of 'ultimate justifications'. What is the character of someone who really believes in Cartesian skepticism? They are paralytically obsessed with the impossibility of knowledge while constantly embodying its use. — fdrake

Well, if they actually follow Descartes then whatever character follows from dualism I suppose :D . Surely the only people who espouse the Cartesian scenario as something which "destroys" knowledge are students of philosophy, and worth engaging for pedagogical purposes only. While that may be the case, I don't think it makes sense to just dismiss the scenario. There are reasonable responses to it.

I suppose what I would say is a reasonable response to Descartes (for surely not everyone who reads Descartes also then goes "all the way" while forgetting the solution) for a student would be to ponder it, not to claim that we have no knowledge. To wonder how, not to adopt the method as actual and forget the solution. Or, as I think most do, passing over isn't all bad. But it does strike me as being a-philosophical.

I do like the Pyrrhonists.



Some other things about skepticism, though: Often times, when someone expresses skepticism on particular things, or on some categories, incredulity is the gut reaction you face. So, say, with God. Or moral facts. Or propositions. In some way I look at the skeptical scenario as a way of thinking through any skeptical problem, at its "limit".