Wow, it must suck being an evil brain jar demon! Question is, what evidence is there for the existence of such a being? None at all. And it's perverse to multiply entities beyond necessity, according to ye olde Bill of Occam. The method of sceptical doubt taken to such extremes that it undermines the very concept; reality - supposedly being investigated, is the rankest sophistry. — karl stone

I'm not saying that the proposed scenario is true, or even justified. I am simply explaining that your attempt at a refutation begs the question.

If you insist on engaging in such arguments, at least accept their true logical implications, which is solipsism; and inability to know anything beyond the mere fact of your own existence. I think therefore I am, and that's your lot. — karl stone

That is indeed what many skeptics claim. We don't/can't know anything (other than that which is logically necessary).

I'm not saying that the proposed scenario is true, or even justified. I am simply explaining that your attempt at a refutation begs the question. — Michael

I appreciate you don't claim the proposed scenario is true, but you are saying it's justified to some degree - if you claim that the occurrence of pain, and instinctive removal of the hand from the fire can all be dismissed as possibly the work of an evil demon, without offering a scrap of proof for the existence of such a thing.

I say that the instinctive removal of the hand from the fire implies an objective reality, not subject to intellectual doubt because it's prior to cognition.

This is why I asked the questions about will - and whether this supposed demon is forcing you to put your hand in the fire? Because, if now, even your thoughts are the work of an evil demon, you cannot claim I think therefore, I am.

Not even Descartes went that far; he considered the fact he was thinking a fundamentum inconcussum; an unshakable truth, even though his body, the evidence of his senses and the world might be doubted, the very fact that he was thinking was the basis to assert with certainty, his subjective existence. I think therefore I am. But this results in solipsism. He cannot assert anything else, having doubted it all away.

Subjectivism offers no proof of the real. And you might say, objectivism is based in ultimately unjustifiable assertions that the world we experience, actually exists, but I say we cannot doubt our hand is on fire, because it hurts!

I think knowledge obtained via the senses can be justified as providing an accurate picture of reality because we evolved, and could not have survived were we misled by our senses.
— karl stone

On the face of it, there is something wrong here. We are frequently misled by our senses, and yet we have survived - or at least enough of us have survived. — Ludwig V

Perhaps it is the brevity of my remarks on a very complex topic!

You'll get a pushback against "you know it is real because you can see it" from the idealists and solipsists, who will claim that it might be an hallucination or other phantasm. — Banno

That position doesn't make sense to me. If what we see is an hallucination or other phantasm, then our eyes must be, also. Hallucinatory eyes hallucinate the sight of a hallucinatory reality. If reality's nature is not such that eyes can give us valid information about it, then I would expect reality to have evolved some other system to do so.

I tried to get to grips with Wittgenstein and failed. I seem to remember semiotics and algebraic propositional logic. He's a bit much!
I'd have learned more reading about Wittgenstein, but I didn't do that either. It makes it quite difficult to respond to the bulk of your post; the failing being on my part, not yours, nor Wittgenstein's - as far as I know.

I'm not an idealist either. Certainly not of the Plato's cave variety: ideal forms of which the real world is but a shadow. Weird! But maybe that's not what you mean by idealist.

I think of myself as a Galilean objectivist; a follower of an untold philosophical tradition - misrepresented by Rand. Galilean objectivism that ought to have resulted from the Church welcoming Galileo's proof of heliocentrism - and his epistemic method as the means to establish valid knowledge of Creation. Scientific truth should have been afforded moral worth, developed and integrated into society, politics and economics over the past 400 years. But wasn't!

Descartes is the father of philosophy, Galileo is nobody, and science is a mere tool put to subjectively conceived ends. And that's why we're doomed!

That position doesn't make sense to me. If what we see is an hallucination or other phantasm, then our eyes must be, also — Patterner

If you're at the Overlook Hotel and you see people who shouldn't be there, you should question whether you're hallucinating.

I wonder how we make sense of such claims as "if I were you then ...." (or to use proper names, "if Michael were Banno then...") — Michael

But this analytic interpretation of the phrase seems misplaced. It's not how we ordinarily understand it. — Michael

Yes. See the exchange above about "If I were Barack Obama . . . " Taken literally, it can only mean "If I were not I . . . " which can't get off the ground. When we say things like "If I were you . . . " we mean either "Here's what I think you should do/think etc." or "If I (still being me!) were in your situation, here's what I would do; perhaps you should do the same."

I appreciate you don't claim the proposed scenario is true, but you are saying it's justified to some degree — karl stone

I’m not saying that it’s justified. I’m saying that your attempt at a refutation begs the question.

The skeptic claims that that even though it seems that the pain you feel is caused by a fire it’s possible that the fire doesn’t exist and that the pain (and the visual image) is caused by something else (something hidden from us) – or by nothing at all.

And your response is to say that the pain you feel is caused by the fire and so the fire is real?

If you say so. I don't see what choice there is but to assume the existence of an objective reality when on fire, because otherwise, as I've shown - you can't assume anything beyond the solipsistic fact of your own existence.
Evidence for an objective reality can be given prior to any doubtable influences of cognition, via the irrefutable experience of pain.
I don't think I'm begging the question at all. I think this is a 'net down for your serves' argument - where you get to engage in the most ridiculous, unfounded, unproven, unjustifiable sceptical arguments while demanding of me shy high standards of absolute proof.
Sophistry and humbug!

I don't think I'm begging the question at all. I think this is a 'net down for your serves' argument - where you get to engage in the most ridiculous, unfounded, unproven, unjustifiable sceptical arguments while demanding of me shy high standards of absolute proof. — karl stone

I'm not asking you to prove that skeptical claims are false; I'm explaining that you haven't proved that skeptical claims are false.

To perhaps better illustrate the difference: I'm not asking you to cook me dinner; I'm explaining that you haven't cooked me dinner.

You're more than welcome to dismiss skeptical claims as being unworthy of consideration (and to refuse to cook me dinner).

Yes. See the exchange above about "If I were Barack Obama . . . " Taken literally, it can only mean "If I were not I . . . " which can't get off the ground. When we say things like "If I were you . . . " we mean either "Here's what I think you should do/think etc." or "If I (still being me!) were in your situation, here's what I would do; perhaps you should do the same." — J

I think you're insisting that a person who didn't have your history, parents, DNA, can't be you. That's a choice regarding essential properties. It's not a necessary stance, I don't think, by way of the Cogito.

That's fair. I was agreeing with Kripke's view here.

EDIT: and it raises the interesting question of whether the cogito generates a personal identity. I'm inclined to say no, but it's certainly arguable.

I'm not asking you to prove that skeptical claims are false; I'm explaining that you haven't proved that skeptical claims are false. — Michael

Skeptical claims? Isn't that a contradiction in terms? I don't think I'm trying to prove anything about skeptical claims per se. I'm addressing the question: 'How do we know what is real?' And also saying that scepticism is a no standards method of demanding impossible standards of objectivism, empiricism and science - when answering the question: How do we know what is real?

In short, sophistry, humbug and balderdash. It's like on the news, when they get a climate scientist with a stack of papers as high as an elephant's eye, to debate a climate denier employed by the fossil fuel lobby, and treat those two as equally valid opinions. Subjectivists have a lot to answer for!

That's fair. I was agreeing with Kripke's view here. — J

I don't think I'm contradicting Kripke. He would agree that essential properties are chosen in context, right? One could refer to an Obama who has certain parents.

Kripke asks (of Queen Elizabeth):

How could a person originating from different parents, from a totally different sperm and egg, be this very woman? . . . It seems to me that anything coming from a different origin would not be this object. — N&N, 113

And at several other places he's clear that what makes a person that person is being born of certain parents. Whether this equates to an essence is a fraught subject, of course.

Can you say more about the context question? I read Kripke as saying, not that one could refer to an Obama who has certain parents, but that we must -- that's where the "baptism" starts.

And at several other places he's clear that what makes a person that person is being born of certain parents. — J

I take him to be assessing the way a person normally comes up in conversation. He's analyzing the way we think and speak, not revealing necessity in the realm of selfhood.

Whether this equates to an essence is a fraught subject, of course. — J

I was referring to the way Kripke uses the concept of essence in N&N. Is that use fraught in your view?

Can you say more about the context question? I read Kripke as saying, not that one could refer to an Obama who has certain parents, but that we must -- that's where the "baptism" starts. — J

Yes. I'll get some cool quotes together. Maybe we could go over the lectern example.

I take him to be assessing the way a person normally comes up in conversation. He's analyzing the way we think and speak, not revealing necessity in the realm of selfhood. — frank

The informal style of N&N does leave this somewhat open, I agree. Kripke certainly talks as if he means not just how we think, but what is in fact the case. He says, for instance:

The question really should be, let's say, could the Queen -- could this woman herself -- have been born of different parents from the parents from whom she actually came? . . . Let's suppose that the Queen really did come from these parents . . . [etc.] — N&N, 112

But you're wondering whether he means, more precisely, to be asking: "Would we refer to this woman as the Queen if she came from different parents?" Possibly. "Necessity in the realm of selfhood" would be something about this woman that must pick her out from all others, in all possible worlds. So we're asking, Can such a property exist, or inhere, within the woman herself, as opposed to within the process of picking-out? One is tempted to reply, "Yes indeed. The genes, the DNA. They are there regardless of whether we use them for any reference-fixing."

the way Kripke uses the concept of essence in N&N. Is that use fraught in your view? — frank

Well, yes, in the sense that he's availing himself of terminology that has a long fraught history. And I'm not sure he's always consistent about invoking essences. For instance, he says, about gold:

Any world in which we imagine a substance which does not have these properties is a world in which we imagine a substance which is not gold, provided these properties form the basis of what the substance is. — N&N, 125

All well and good, but is "properties that form the basis of what the substance is" the same thing as "essence" or "essential properties"? How does an essence, if that's what we're talking about, form the basis? Again, the conversational character of the book makes me want a bit more precision. A brilliant book nonetheless.

I'll get some cool quotes together. — frank

Excellent.

But you're wondering whether he means, more precisely, to be asking: "Would we refer to this woman as the Queen if she came from different parents?" Possibly. "Necessity in the realm of selfhood" would be something about this woman that must pick her out from all others, in all possible worlds. So we're asking, Can such a property exist, or inhere, within the woman herself, as opposed to within the process of picking-out? One is tempted to reply, "Yes indeed. The genes, the DNA. They are there regardless of whether we use them for any reference-fixing." — J

I guess the wildcard is how you pick yourself out in (or at) possible worlds. If you identify yourself as the person with particular parents, then you can't be Obama. If you get existentialist about it and you're 'that quality of being that comes to rest in the sanctuary of the form' as Kierkegaard put it, then the door would be open to a plot like Being John Malkovich. I think the point I'm making is pretty obscure and wouldn't come up very often.

Well, yes, in the sense that he's availing himself of terminology that has a long fraught history. — J

Sometimes you need a little fraught in your life. Do you want to examine the lectern example in this thread? Or a different one?

This makes the issue much more precise, thanks. I agree that my question may be, in part, a question about syntax and semantics, about what can be said pre- and post-interpretation.

My question was:

". . . whether "how a reference is fixed for X" is part of the list of X's potential properties; or whether we're mixing discourses by thinking of it that way." - J

I'll switch back to "a" rather than "X", to fit your usage.

So reference-fixing is giving an interpretation, yes? We're agreeing what "a" will stand for. Now a will also have a number of properties. Let's say a is the Eiffel Tower. We can list some of them: tall, made of metal, speaks French :wink: etc. And you're pointing out that, if I additionally ask about how "a" comes to stand for the Eiffel Tower, we can't answer that in terms of the interpretation of "a" -- that is, the various properties that can now be predicated of a based upon our interpretation. We have to move to a different level and talk about how or why "a" has the reference it has, which is not a feature or property of a, any more than my name is a property of me.

If I've got this right, then my only question is: Is "syntax" the right name for this second level? Doesn't all the syntax get specified before any a or b or c can be referred to? A question about reference-fixing doesn't seem syntactical so much as stipulative. As you say:

Notice the difference between saying that a is f, f(a), which happens within the interpretation, and saying that "a" stand for a, which is giving (stipulating) the interpretation? — Banno

I guess my question is why giving the interpretation qualifies as syntactic. I would have said that both kinds of statements are semantic, it's just that one happens within the interpretation and the other does not. Does that make it syntactic by default? So that the best way to think about "'a' stand for a" is as a syntactical premise?

Do you want to examine the lectern example in this thread? Or a different one? — frank

Not surprisingly for a thread called "What is real?" this one has taken a lot of detours. How about a new thread?

I'm pleased to see so much analytic work going on. Working through the issues is the only way to work out how to fit all these pieces together - if that is possible.

This is core analytic philosophy - looking closely at how the terms involved are being used, comparing them with formal systems we know are consistent, seeing what works and what does not. Bread and butter stuff. It's hard conceptual work.

I wonder how we make sense of such claims as "if I were you then ...." — Michael

@J gave a pretty clear account of this, don't you think? Together with @frank's account of how we identify an individual with their origin, which is the approach Kripke is arguing for in Naming and Necesity.

Seems to me you are correct that @karl stone hasn't succeeded in casting aside the sceptic.

If reality's nature is not such that eyes can give us valid information about it, then I would expect reality to have evolved some other system to do so. — Patterner

There's something deeply problematic about using evolution to explain away ontological problems. Evolution assumes a degree of realism in assuming that there is a deep past in which there are things that could evolve, so of course it is consistent with realism. But it would be a mistake to think that evolution demonstrates realism.

None of which is to say that evolution didn't occur. It's just not methodologically a good way to try to dispose of solipsism or idealism.

Now it seems to me that despite his protestations against Cartesianism, @karl stone is buying in to many of the assumptions that Descartes made. He wants to find firm foundations and build a system from those foundations, a very Cartesian method. Sure, instead of the cogito he wants to use perception as that foundation, but it isn't going all that well.

Of course I agree with @Sam26 that a response is found in a treatment of what it is to doubt, along the lines of Wittgenstein's discussion of hinge propositions, but unlike Sam I reject idealism, along with certain sorts of realism, as a false juxtaposition.

But the devil is in the detail, and the way forward is to keep struggling with the analysis.

Not surprisingly for a thread called "What is real?" this one has taken a lot of detours. How about a new thread? — J

While looking for an online copy of N&N I can copy from, I came across this paragraph from lecture 3. It touches on the question of whether Kripke was doing analysis or building a metaphysical picture:

Descartes, and others following him, argued that a person or mind is distinct from his
body, since the mind could exist without the body. He might equally well have argued the
same conclusion from the premise that the body could have existed without the mind.
Now the one response which I regard as plainly inadmissible is the response which
cheerfully accepts the Cartesian premise while denying the Cartesian conclusion. Let
'Descartes' be a name, or rigid designator, of a certain person, and let 'B' be a rigid
designator of his body. Then if Descartes were indeed identical to B, the supposed
identity, being an identity between two rigid designators, would be necessary, and
Descartes could not exist without B and B could not exist without Descartes. The case is
not at all comparable to the alleged analogue, the identity of the first Postmaster General
with the inventor of bifocals. True, this identity obtains despite the fact that there could
have been a first Postmaster General even though bifocals had never been invented. The
reason is that 'the inventor of bifocals' is not a rigid designator; a world in which no one
invented bifocals is not ipso facto a world in which Franklin did not exist. The alleged
analogy therefore collapses; a philosopher who wishes to refute the Cartesian conclusion
must refute the Cartesian premise, and the latter task is not trivial — Naming and Necessity, Lecture 3

Notice that Kripke isn't here worried about whether Descartes was right or wrong. He's exploring what happens from various starting points. If we start with accepting that the mind could be distinct from the body, we can't subsequently assert that there's a necessary connection between the two. We can gather evidence of that in some way, but that's it.

Now it seems to me that despite his protestations against Cartesianism, karl stone is buying in to many of the assumptions that Descartes made. He wants to find firm foundations and build a system from those foundations, a very Cartesian method. Sure, instead of the cogito he wants to use perception as that foundation, but it isn't going all that well. — Banno

It's fine from my end. I don't think I've bought into Cartesian assumptions; indeed, wasn't Descartes purpose to establish certainty, to avoid assumptions? I don't think he was particularly successful. Indeed, I don't believe he believed what he claimed to believe. I think he saw what happened to Galileo, and wrote an alternate epistemology more consistent with doctrine to cover his own backside.
Here we are addressing a question that's not central to my philosophy. How do we know what is real? - is a subjectivist question.
As a Galilean objectivist it's not a question I would ask; and requires drawing from various areas to answer. I do not base Galilean objectivism in the pain/pleasure principle of evolving life; I might resort to empiricism - which is to say, reconciling observations in terms of an hypothesis, and having independent confirmation of my observations.
I'm not wondering if what I observed even exists, or if I hallucinated the existence of an objective reality. That's a subjectivist concern.

I'm pleased to see so much analytic work going on. Working through the issues is the only way to work out how to fit all these pieces together - if that is possible.

This is core analytic philosophy - looking closely at how the terms involved are being used, comparing them with formal systems we know are consistent, seeing what works and what does not. Bread and butter stuff. It's hard conceptual work. — Banno

Same.

wasn't Descartes purpose to establish certainty, to avoid assumptions? I don't think he was particularly successful. Indeed, I don't believe he believed what he claimed to believe. I think he saw what happened to Galileo, and wrote an alternate epistemology more consistent with doctrine. — karl stone

He didn't establish certainty to avoid assumptions. He did not believe what he claimed to believe with respect to radical skepticism -- he explicitly says it's a methodical doubt rather than a doubt about the world.

I think he withheld his publication of The World after seeing how Galileo was treated, but his philosophy differs from that.

No. Descartes withdrew the work on physics first, and wrote Meditations afterward. While Galileo was on trial. I don't think Descartes believed subjectivism was a valid epistemology. He was scared of doing science, and covering himself against the threat of being declared a heretic.

This makes the issue much more precise, thanks. — J

Cheers.

The difference between syntax and semantics is very clear in formal logic. Less so in natural languages. The following is probably familiar.

Let's look briefly at propositional logic. It includes just letters, p,q, and so on, as many as you want, and a couple of symbols, usually v and ~. To this we add formation rules that tell us what we are allowed to write. First, we can write any letter by itself. So we can write "p", or we can write "q". Then, we are allowed to put a "~" in front of anything else we are allowed to write; so we can write "~p" and "~q" and so on. Then, for two things we can write, we can join them with a "v". So we can now write "~pvq". From this, we can set out a system that shows how some strings of letters are well-formed - they follow the formation rules - while others are not... if we follow those rules we can never write down "pvvq~", for example. (I've left out brackets just to keep things simple. Also, ^ and ⊃ can both be defined in terms of v and ~, so they are not needed here)

All we have here is a system of syntax. It is purely a set of rules for stringing letters together in a specific way. In particular, it tells us nothing of what "p" and "q" stand for, and so nothing of which of our strings of letters might be true or false.

We add an interpretation to this syntactic system by ascribing "T" or "F" to each of the letters, together with a rule for the truth functionality of "v" and "~". A string beginning with "~" will be T if and only if the stuff after the "~" is F, and a string joined by a "v" will be T if and only if the stuff on either side of the "v" is also T.

A useful way to understand this is that p,q, and so on denote either T or F. We've moved from syntax to semantics.

We can expand our syntactic system by allowing ourselves to write not just p's and q's, but also "f(a)" and 'g(b)" and so on, in the place of those p's and q's. We can add rules for using ∃(x), but still at the syntactic level - just setting out what is well-formed and what isn't. This gives us a bigger system.

And to that we add more interpretation, were the letters "a","b" and so on stand for a and b, respectively, and "f" stands for some group of such letters, perhaps "f" stands for {a,c,e} while "g" stands for {b,c} or whatever. We then get that f(a) is true - "a" is in the set {a,c,e}, while f(b) is false - "b" is not in the set {a,c,e}. Similar rules apply for interpreting the quantifiers. And this gives us predicate calculus.

We can then expand the system once more, adding the operator "☐" outside of all of the stuff in the syntax for predicate logic, together with a few rules for how we can write these. This gives us the systems S1 through S5. These are just ways of writing down strings of letters, with ever more complicated permutations.

In order to give a coherent interpretation to these systems, Kripke taught us to use possible world semantics. In a way all this amounts to is a process to group the predicates used previously. So we said earlier that "f" stands for {a,c,e}, and to this we now add that in different worlds, f can stand for different sets of individuals. So in w₀ "f" stands for {a,c,e}, while in w₁ f stands for {a,b}, and so on in whatever way we stipulate - w₀ being world zero, w₁ being world one, and so on. Now we have added a semantics to the syntax of S4 and S5.

So reference-fixing is giving an interpretation, yes? — J

Exactly.

We have two levels, if you like, for each system. At one level we just set out how the letters can be written out, what sequence is acceptable. That's the syntax. At the next level, we add an interpretation, what the letters stand for. That's the semantics. So for propositional logic, the letters stand for T or F, and for predicate logic, we add individuals a,b,c... and for modal logic we add worlds, w₁, w₂ and so on, in order to get out interpretation, our semantics.

And to this we might add a third level, where we seek to understand what we are doing in a natural language by applying these formal systems. So for propositional logic, we understand the p's and q's as standing for the sentences of our natural language, and T and F as True and False. For predicate logic, we understand a,b,c as standing for Fred Bloggs, the Eiffel tower and consumerism, or whatever. And in modal logic, we get Naming and Necessity, where we try to understand our talk of modal contexts in natural languages in terms of the formal system we have developed.


I left out brackets, truth tables, domains, and accessibility, amongst other things, and only scratched the surface of extensionality. But I hope I've made clear how clean the distinction is between syntax and semantics in formal systems.

Cool, I don't have that deep a knowledge of the sequence of events in his life so I'll go with it.

But I know Descartes was not scared of doing science; covering himself from the ignorant, sure. And I agree he didn't think "subjectivism" is a valid epistemology -- that's not his thing. It's methodical, and not metaphysical, doubt.

He wrote the meditations afterwards -- but it's still a methodical doubt, but like you noted: People often like the question but reject the answer.

I don't think I've bought into Cartesian assumptions — karl stone

I'll try to explain the assumption again. It's ubiquitous, and so can be difficult to see.

Descartes supposes that we have on the one hand, mind, and on the other, the stuff of the world; roughly the presumption is that of dualism, of a divide between what is subjective and what is objective. Immediately on making this supposition he, and we, are faced with the problem of how the stuff of the mind interacts with the stuff of the world. Descartes solution was god, your solution is observation.

But what if that supposition, that schism between thought and thing, were a mistake?

I'll leave that hanging. Thoughts?