As with thinking, no, they are not. They may have public exhibition, but they are not themselves public. — Mww

Let's call concepts that people think with privately, according to your or Sellars' Jones' theory. Let's call koncepts what philosophers use to talk and make claims. Then koncepts are public and what actually matters here.

The common mistake of confounding the thing with the use of the thing. — Mww

I suggest that it's not confusion but simply a matter of replacing a broken theory with something better. Instead of what's essentially a theology of mystic Forms, we develop the insight that meaning is use, talking instead of second nature and norms.

From the fact that 'existence' is a public word it does not follow that existence is a public concept. — Janus

I'm not so sure about your logic there, but I don't need that assumption. I hope at least a few people are enjoying their popcorn as you lecture me on the proper way to understand concepts, while insisting that they are private, that they mean whatever they look like to the little ghost in our pineal glands. Once you see it, the self-contradiction will be so glaring that you'll be amazed how cozy you were with it for so many years. Repent in sackcloth and ashes ! For you call black white and one zero. (Kidding.)

We each have our own range of associations, intuitive feelings and idiosyncratic understandings of the meaning of the word. — Janus

No one needs to dispute this. Just as some of us are nearsighted and colorblind and we don't see the world in the same way but do see the same world, there are also varying levels of mastery of using a concept, along with idiosyncratic uses that are sometimes adopted more widely.

I speculate that it's the very background theological bias I'm criticizing that's tempting my opponents to insist that concepts must be crystalline and perfectly definite to be public. That's like thinking the Charleston (the dance) is perfectly definite or that there's one exactly right way to perform a song.

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From birth, I think two. Just another person, but obviously, for ethical reasons no-one's been able to test that.
#After a while though, one is sufficient because we can engage the social imagination and use the public concepts we imagine are available, even if they aren't. — Isaac

This is a good point to stress. Our Robinson Crusoe Cartesians like to take a result as if it were the given itself. I may end up a taciturn Heraclitus too wise for the company of others, but I started as a baby who couldn't lift my neck and (presumably) without even a concept that I was this self as locus of responsibility, tracked for what becomes 'my' promise-keeping and the reliability of 'my' wolf-reporting.

To show that we have a private concept of 'exists' you need to show not only that mental activity is private, but that the grouping of some of that mental activity into a clear concept called 'existence' is also private. — Isaac

Typically, some metaphysical version of 'private' is intended in these cases. I take it to be grammatical, in that it's, by definition, not empirically decidable. The arbitrarily convincing P-Zombie is ( by definition ) all science can ever touch with its scalpels and scanners. What we end up with is a mystified X, with no content save the thereness of the there itself. We are back to building shrines for tautologies.



From Ryle's SEP entry:

Ryle’s criticism of the Official Doctrine begins by pointing out an absurdity in its semantic consequences. If mental conduct verbs pick out “occult” causes then we would not be able to apply those verbs as we do; so something must be wrong with a theory of mental phenomena that renders so inadequate our everyday use of these verbs. For, according to the Official Doctrine

when someone is described as knowing, believing or guessing something, as hoping, dreading, intending or shirking something, as designing this or being amused at that, these verbs are supposed to denote the occurrence of specific modifications in his (to us) occult stream of consciousness. (1945, 17)

Ryle’s criticism of the view is that if it were correct, only privileged access to this stream of consciousness could provide authentic testimony that these mental-conduct verbs were correctly or incorrectly applied. “The onlooker, be he teacher, critic, biographer or friend, can never assure himself that his comments have any vestige of truth.” And yet,

it was just because we do in fact all know how to make such comments, make them with general correctness and correct them when they turn out to be confused or mistaken, that philosophers found it necessary to construct their theories of the nature and place of minds. Finding mental-conduct concepts being regularly and effectively used, they properly sought to fix their logical geography. But the account officially recommended would entail that there could be no regular or effective use of these mental-conduct concepts in our descriptions of, and prescriptions for, other people’s minds. (1949a, 17)

There seems to be this sense that because we can imagine a horse, the concept of a horse must be private (I needn't tell anyone what colour it is...shhh!)

But we cannot simply derive the concept of a horse. All we're doing in imagining one is rehearsing the various mental events which took place when we had a horse pointed out to us, and then experimentally changing abstracted properties (which we also had pointed out to us) like the colour or the shape.

But the point is, to paraphrase Wittgenstein, if we kept on, in isolation, repeating that rehearsal, making small errors each time, until our imagined horse looks remarkably like a hippopotamus, then we'd all agree that we'd got the concept wrong. What we're imagining is not a horse, it's a hippopotamus. So my imagination cannot be the concept 'horse', otherwise it couldn't be wrong. Something else has to actually be the concept. My imagination seeks to practice it, correcting its errors by reference to the actual concept in all its dynamic, ever-changing, public, glory.

There seems to be this sense that because we can imagine a horse, the concept of a horse must be private (I needn't tell anyone what colour it is...shhh!) — Isaac

Precisely. The trivial possibility of keeping a secret (which isn't always so easy, by the way) is radicalized into an quasi-mathematically NSA-proof beetle-box (infinitely encrypted, robust against the high-tech prying of the Neptunian secret police circa 4059.

What we're imagining is not a horse, it's a hippopotamus. So my imagination cannot be the concept 'horse', otherwise it couldn't be wrong. — Isaac

Exactly. The OP is about our minimal rational epistemic commitment. If words mean whatever we think they mean, we can't even begin to settle beliefs rationally.

Just as keeping a secret is radicalized into an inaccessible ghost as that alone which is given, so is the fact that mastery of a concept varies radicalized into an absurd essential privacy of concepts.




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I understand your dukkha - something's wrong, I second that motion. — Agent Smith

Perhaps elaborate ?

Trying to argue against the coherency of solipsism is just wrong. — Michael

Wrong within the dream of the solipsism or wrong for any rational agent ? If the concepts he discusses do not transcend the epistemological solipsist (play the role of something external), then his claims seem to lose their status as genuinely philosophical.

I do not deny that madmen can fear they are caught in a dream. I dispute that the philosopher as such (willingly subject to the force of the [non-subjectively ] better reason) could coherently impugn the 'externality' of their own concepts, essentially asserting, if an epistemological solipsist, that it's wrong to assume we could be wrong.

if an epistemological solipsist, that it's wrong to assume we could be wrong — Pie

If you're going to continue to argue against this strawman then there's no point in me continuing. The epistemological solipsist doesn't claim that no claim is truth-apt. How many times do I have to explain this?

What can truth-apt mean for a philosophical solipsist ? ( But we can drop if if you want.)

In philosophy, to say that a statement is truth-apt is to say that it could be uttered in some context (without its meaning being altered) and would then express a true or false proposition.

How can I make a statement that's true or false without something I can be right or wrong about ?

How can I make a statement that's true or false without something I can be right or wrong about ? — Pie

I can be wrong about things that don't exist. If I claim that God exists then my claim is false if God doesn't exist. If I claim that you have private thoughts and sensations then my claim is false if you don't have private thoughts and sensations. If I claim that mind-independent objects exist then my claim is false if mind-independent objects don't exist.

Solipsism is a skeptical position, and skepticism is the position that we could be wrong. That you are somehow turning it into the position that we can't be wrong should show you how mistaken you are.

skepticism is the position that we could be wrong. — Michael

What is it that we could be wrong about, according to the skeptic (in this case the epistemological solipsist), who makes an assertion about us ?

What is it that we could be wrong about, according to the skeptic, who makes an assertion about us ? — Pie

Any thinking thing, whether there be just one thinking thing or two thinking things or seven billion thinking things.

Any thinking thing, whether there be just one thinking thing or two thinking things or seven billion thinking things. — Michael

Is this just the solipsist's conception of a thinking thing (a 'private concept,' if that makes sense) ? Or do his claims aim at truths about a concept that binds all rational agents ?

I claim that that concept itself is either external or not worth talking about. His statements about the concept are either truth-apt (and can thus be wrong) or not. If truth-apt, then external.

I claim that that concept itself is either external or not worth talking about. — Pie

I have no idea what it means to say that a concept is external. Is the concept of a horse something that I can encounter and pick up?

FWIW, I don't think there's a perfectly 'right' answer here. We are clarifying concepts as we debate an edge case.

I have no idea what it means to say that a concept is external. Is the concept of a horse something that I can encounter and pick up? — Michael

Why do you assume that the external is an object? It's just a spatial metaphor.

I've already suggested a 'safer' more neutral understanding of this metaphor.

Why do you assume that the external is an object? — Pie

Because that's the kind of external thing that the solipsist says cannot be known to exist. If you mean something else then you're not addressing the solipsist's claim.

It's just a spatial metaphor. — Pie

Could you explain it without using a spatial metaphor?

Is the concept of a horse something that I can encounter and pick up? — Michael

Is it something you can be right or wrong about ? Can one be wrong about the square root of 2 ? Or whether a promise was made ? If not, why not ?

You could explain it without using a spatial metaphor? — Michael

I've suggested that we look to the appearance/reality distinction that probably informs this issue in the first place. Reality plays the role of the 'external.' Appearance (the given, the internal) can deceive me, so I can mistake (have incorrect beliefs about) the external.

The skeptic seems to need this picture, this distinction, to get off the ground.

Can one be wrong about the square root of 2 ? — Pie

Yes. And one can be wrong about the square root of two even if one cannot know that other minds and mind-independent objects exist. Which is precisely why it is wrong to say that epistemological solipsism entails that no claim is truth-apt.

But note that I'm accusing the solipsist of conceptual incoherence, which is to say wrong in terms of the universal rational norms that bind the philosopher as such. The very notion of philosophy binds its participants to something self-transcending.

If I can't be wrong about the concept of knowledge, it's not external to me. If I can be wrong about the concept of knowledge, it is external to me. If I assert, in the name of reason, in its authority, that knowledge of the external is necessarily uncertain, I present knowledge that's intended to transcend me toward the very concepts that secure my role as philosopher. The madman can say it, but the philosopher cannot.

I can't prevent you from softening the meaning of 'external' to make your case. I just think that you simultaneously diminish the significance of the claim, as if the solipsist is merely denying a particular metaphysics of the external world (such as Epicurean atomism, or the 'reality' of everyday objects) --- as opposed to the external world itself.

And one can be wrong about the square root of two even if one cannot know that other minds and mind-independent objects exist. — Michael

I believe the square root of four is one. But it isn't, it's really two.

The belief is in my mind.

Where's the real fact?

I can't prevent you from softening the meaning of 'external' to make your case. I just think that you simultaneously diminish the significance of the claim, as if the solipsist is merely denying a particular metaphysics of the external world (such as Epicurean atomism, or the 'reality' of everyday objects) --- as opposed to the external world itself. — Pie

But that “soft” externality is the kind of externality that the solipsist denies can be known. They don’t deny knowledge of the metaphorical externality that you apply to such things as maths. The solipsist accepts that we can get maths wrong.

I believe the square root of four is one. But it isn't, it's really two.

The belief is in my mind.

Where's the real fact? — Isaac

It’s not anywhere. I reject mathematical Platonism.

It’s not anywhere. I reject mathematical Platonism. — Michael

So against what measure am I comparing my belief that the square root of four is one, in order that it is wrong?

But that “soft” externality is the kind of externality that the solipsist denies can be known. They don’t deny knowledge of the metaphorical externality that you apply to such things as maths. The solipsist accepts that we can get maths wrong. — Michael

To me the tricky part is that the solipsist is making claims about any rational agent, existence or not. Your counter might be that 'If X exists, then X has nature N,' but this is still a claim about what is possible and impossible in the world. It can be framed like this : It is this case that it's impossible that a rational agent both exists and is legitimately certain that ...