Consider though : their claim is about other minds. Other minds can't know whether there are other minds. The keyword is we. — Pie

Yes. What's wrong with that? Just as there can be an agnostic theist there can be an epistemological solipsist who isn't an ontological solipsist. They just accept that we cannot know that there are other minds, but nonetheless believe that there are.

es. What's wrong with that? — Michael

"Other minds cannot know there are other minds." They are describing an essential feature of the thing they simultaneously doubt.

We can try to repair this: "If there are other minds, then those minds can't know there are other minds." But this is a statement about the very minds that might not exist. At the very least it's a claim about shared conceptual space. The public concept of mind is in play, even if there's purported doubt about its appropriate application.

We can try to repair this: "If there are other minds, then those minds can't know there are other minds." But this is a statement about the very minds that might not exist. — Pie

And? If there is the Christian God then he is a dick. The statement is about the very God that might not exist. What's the problem? The existence of something is not entailed by there being some true claim about it.

Edit: In fact, I think it can be correct to say that the Christian God is a dick even if he doesn't exist, and so it can be correct to say that others minds cannot know that there are other minds even if they don't exist.

And? If there is the Christian God then he is a dick. The statement is about the very God that might not exist. What's the problem? The existence of something is entailed by there being some true claim about it. — Michael

To me that's a misleading analogy. If I claim there is a God, I'm saying that for both us there is a God. It's a fact about our world in common that there's a God in it. Maybe I'm wrong. The world is there, and maybe God isn't in it, despite my claim.

If I say, on the other hand, that it's a fact about our world together that we might not have a world together, that's different. I'm not making sense. Let's try this : It's a fact about our world that there might not be facts about our world. Still doesn't work.

Simpler: it's a fact that there are no facts. Or it's fact that there might not be facts.

To me that's a misleading analogy. If I claim there is a God, I'm saying that for both us there is a God. It's a fact about our world in common that there's a God in it.

If I say, on the other hand, that it's a fact about our world together that we might not have a world together, that's different. — Pie

You seem to be saying that if p → q is true then p is true, but that's an invalid inference. p → q is true even if p is false. In this case, p is "there are other minds" and q is "these other minds cannot know that there are other minds".

There are two issues here:

1) Modern skepticism. The problem of judgment, based on a theory of ideas or mental representation.

2) Descartes' doubt, which serves both an epistemological as well as protective rhetorical function.

1) The things we see are not present in the mind. What we see are representations. The problem of judgment arises because we cannot compare these representations to the things themselves in order to determine whether the representation is true to what it represents.

2) Under the guise of finding something indubitable, by doubting everything, Descartes could indirectly call into doubt the authority of the Church. He usurps of the authority of the Church with the authority of the thinking self.

He does not doubt because of some existential crises. It is deliberate and methodical:

To-day, then, since I have opportunely freed my mind from all cares and am happily disturbed by no passions, and since I am in the secure possession of leisure in a peaceable retirement, I will at length apply myself earnestly and freely to the general overthrow of all my former opinions. [Meditations, 1.1]

Descartes did not doubt that the Church was a threat. It is worth mentioning that he took Ovid's motto as his own:

He who lived well hid himself well.

If we are to understand Descartes we must discover what he is hiding in his apparent agreement with the Church on matters of the soul and God. The 4th Meditation, "Of Truth and Error", is a good place to start. In short, the Cartesian enterprise is about the perfection of man.

I’ll make another argument. It is possible that the number of minds is finite and it is possible that every mind is mortal. It is possible that every mind except one dies. Therefore it is possible that only one mind exists. Nothing about this scenario is incoherent, therefore the solipsist’s claim that only one mind exists is coherent. The coherency of the conclusion doesn’t depend on any of the premises being (or having been) true.

Funny you mention that. I was thinking about the edge case of the last survivor of a nuclear war. But then it's just a contingent fact that other minds don't exist. We're not in the original situation of worrying about apparent minds that might be p-zombie or fantasies.

Another point: I'm guessing that some people imagine the solipsist as living in a world like ours that 'may' be just his fantasy, and they imagine him (problematically, in my view ) being able to make claims that are wrong or right about this fantasy world.

1) The things we see are not present in the mind. What we see are representations. The problem of judgment arises because we cannot compare these representations to the things themselves in order to determine whether the representation is true to what it represents. — Fooloso4

This is the 'veil of ideas' I had in mind. It only becomes plausible in the first place from because one person can sees the eyes of another point at an object, weaving both into a single explanatory/causal nexus. Then the trick happens. The sense organs are implicitly made their own product as we pretend we can start intelligibly behind this veil.

It's not 'I think' but 'we think.' — Pie

You stipulated Descartes’ cogito, so it follows from the original French (1637) Discourse on Method, Pt 4.....

“... je pense, donc je suis....”

.......and subsequently in First Principles 1. 7., 1644.....

“....So this item of knowledge—I’m thinking, so I exist—is the first and most certain thing to occur to anyone who philosophizes in an orderly way....”

....that ol’ Rene intended it to be understood cogito relates to individuals, even if speaking in general regarding all individuals. So...it is “I think”, not “we think”. You know.....philosophizing in an orderly way.
———-

Unless of course it's not just babble...and you appeal to a reason or logic that binds us both... — Pie

I do so appeal, but only insofar as it is at least counterproductive, and at most utterly absurd, to suppose we are not of the same intellectual character. In whatever form that character manifests, does nothing to detract from the fact that there is one, and it is common to all of us. Otherwise, one relinquishes his claim to being human.

That being said, philosophizing in an orderly way completely destroys.....

....the assumption that the external world, the one beyond 'my' experience, is merely a more or less reasonable hypothesis. — Pie

.....insofar as the external world in toto is the ground of my experience, which makes explicit the external world beyond my experience, is no less the external world, but only of my possible experience. What the external world beyond my experience, and thereby the possible experience of it, can be....is a reasonable hypothesis. Conditioned by changes in time, not the permanence in reality.

Philosophizing in an orderly way reduces our minimal epistemic commitment to.....granting that for which the negation is impossible. Which, ironically enough, gets us right back to Descartes’ philosophy that everybody hates.

But then, “in an orderly way” is a subjective judgement, so, there is that.......(sigh)

.

I do so appeal, but only insofar as it is at least counterproductive, and at most utterly absurd, to suppose we are not of the same intellectual character. — Mww

That's one the main points I've been making, friend ! Reason is one and universal or we are just babbling here.

....that ol’ Rene intended it to be understood cogito relates to individuals, even if speaking in general regarding all individuals. So...it is “I think”, not “we think”. You know.....philosophizing in an orderly way.
———- — Mww

This is what needs 'fixing.' We rational ones ought not care at all what lil' Rene smarty pants figures out just for himself.

I persist, sir. It's 'we think' or you and I babble.

Philosophizing in an orderly way reduces our minimal epistemic commitment to.....granting that for which the negation is impossible. Which, ironically enough, gets us right back to Descartes’ philosophy that everybody hates. — Mww

Your view is so close to mine. Do you not see that ?

I'm bothering to fix Descartes because I think he was almost saying the right thing. He didn't emphasize what was implicit...that reason and language (norms for applying concepts) transcend his little ghost driving his little machine from up in its pineal gland. They must. Or the whole thing's ghost babble.

My states of mind, my thoughts and sensations, are phosphorescently present for me, infinitely intimate. I can no more be wrong about what I mean by a word or how I see a patch of color than 2 + 2 can equal 5. And so on. — Pie

I hope this is relevant.

I once started a thread called "You don't need to read philosophy to be a philosopher." Turns out I was at least partly wrong. You may not need to read books, but you at least need to watch videos.

Philosopher Fredrick Copleston was interviewed by Brian Magee on Schopenhauer's philosophy. He said that Schopenhauer carried on Kant's examination of the unknowable thing-in-itself, nomena. Schopenhauer wrote that there is no way we can directly experience noumena. He qualified that somewhat by saying that the only place we can approach such an experience, though partially and imperfectly, is through our personal experience of ourselves - each of our "phosphorescently present," "infinitely intimate" personal experience of ourselves.

He said that Schopenhauer carried on Kant's examination of the unknowable thing-in-itself, nomena. — T Clark

Yes, indeed. I think Schop called it an X and decided it was Will (if memory serves.) I liked Schop for lots of his scaffolding, not so much for this particular theory, except as poetry or myth perhaps.

This 'veil of ideas' has proved to be a seductive metaphor indeed.

Ideas are among the most important items in Descartes’ philosophy. They serve to unify his ontology and epistemology. As he says in a letter to Guillaume Gibieuf (1583–1650), dated 19 January 1642, “I am certain that I can have no knowledge of what is outside me except by means of the ideas I have within me.”

I take the metaphor to be that we look through lens, never at reality directly. Taken in a limited sense, this is not problematic. The nearsighted person sees the tree differently than the eagle. But taken absolutely, we cast an unspeakable void behind the lens...and then find ourselves debating if we can be sure that other people aren't p-zombies or illusions...

I seem to see other people, but I can't be sure, because what I mean by person is roughly what I mean by 'I,' this existence I know 'directly.' My states of mind, my thoughts and sensations, are phosphorescently present for me, infinitely intimate. — Pie

I think a good understanding of the Philosophical Investigations and especially On Certainty should dispel one of the notion that our internal “states of mind, [our] thoughts and sensations” are things which we “know directly.” We simply have these experiences. In other words, we don’t learn that we have these experiences, as if we discover them through some investigation.

To know means to have an understanding of what it means to know, and what it means to not know in a given context. Otherwise, we could infer that someone knows based on their claim that they know. So, how would a doubt arise in this context? The very act of doubting shows a particular state of mind (shows that it exists). If you can’t doubt someone’s claim to knowledge, then you can’t know that it is knowledge. It’s not a matter of knowing at all, no more than I know I’m having a pain in my foot, as I scream out holding my foot, which is bleeding profusely.

The act of knowing is not a private matter, which is what this quote implies. I know based on my direct experience with my inner self. As if knowing is directly connected with some inner thing. This is an easy mistake to make. It’s a confusion between my subjective certainty and objective certainty (knowledge). It’s as if we equate feeling certain with being objectively certain, or knowing. They are not the same, but they are often confused.

The act of knowing is not a private matter, which is what this quote implies. — Sam26

Yes. I tried to present a version of a picture that holds many philosophers captive even now. I understand Sellars to have shown that even sensation words, used often in noninferential reports, still get their meaning from claims linked to those reports inferentially. For instance, I might explain running the red light in terms of thinking the light was green. I might explain Joe's reports of flashes of white light by the pressure he's putting on his eyes with his finger.

I also agree that knowing involves understanding how 'know' ought to be applied. A thermometer can reliably 'answer' a simple question, but it's not making a claim in the space of reasons.

But then it's just a contingent fact that other minds don't exist. We're not in the original situation of worrying about apparent minds that might be p-zombie or fantasies. — Pie

Regardless of what brings about the situation where only one mind exists (it could be that there were other minds but they died, or it could be that only one mind ever came into being), the claim that just one mind exists (or that only one mind can be known to exist) is coherent, contrary to your objection.

I'm guessing that some people imagine the solipsist as living in a world like ours that 'may' be just his fantasy... — Pie

I don't know why you think it would be a fantasy. Experiences are real, not made up.

... and they imagine him (problematically, in my view ) being able to make claims that are wrong or right about this fantasy world.

I think this may be part of where you're going wrong. I can talk about things that don't exist. Even if atheism is true I can talk about God, and if I claim that God exists then my claim is false. Even if solipsism is true I can talk about an external material world, and if I claim that such an external material world exists then my claim is false. Even if solipsism is true I can talk about other minds, and if I claim that other minds exist then my claim is false.

I can also make true or false claims about my experiences. I can feel pain and yet claim not to feel pain. So even claims about my "fantasy" world are truth-apt.

:fire:

It is possible that the number of minds is finite and it is possible that every mind is mortal. It is possible that every mind except one dies. Therefore it is possible that only one mind exists. — Michael

As a categorical statement, the conclusion does not follow from the antecedent hypotheticals.

Nothing about this scenario is incoherent, therefore the solipsist’s claim that only one mind exists is coherent.

Circular fiat. :roll:

The coherency of the conclusion doesn’t depend on any of the premises being (or having been) true.

Without all of the premises being true, your argument is not a sound one, sir. And, as pointed out, even (your) reliance on logic – normative rationality – presupposes selves-other-than-yourself (i.e. discursive community), which shows that your apologia, like "the solipsist's claim" itself (as well as Descartes' "Cogito"), is a performative contradiction.

Without all of the premises being true, your argument is not a sound one, sir. — 180 Proof

It's not supposed to be a sound argument. It's supposed to show that the claim "only one mind exists" is coherent.

And, as pointed out, even (your) reliance on logic – normative rationality – presupposes selves-other-than-yourself — 180 Proof

I don't understand this. Classical logic (and others) doesn't depend on there being other people. Even if I'm the last (or first) man alive, the various axioms and rules of inference hold. The law of noncontradiction doesn't just fade away in a nuclear holocaust where I'm the only survivor.

It's not supposed to be a sound argument. It's supposed to show that the claim "only one mind exists" is coherent. — Michael

As I've pointed out, your argument doesn't even do that.

Classical logic (and others) doesn't depend on there being other people.

Non sequitur; I neither claimed nor implied as much. Your / solipsist's reliance on logic, however, presupposes others. Read what I actually wrote again.

I claim that the minimum rational intelligible epistemic situation is a plurality of persons subject to the same logic and together in a world that they can be right or wrong about. — Pie

Your view is so close to mine. Do you not see that ? — Pie

I can be right or wrong about the world all by myself, thank you very much. So, no, I don't see it, sorry.

It is possible... — Michael

If...

the claim that just one mind exists (or that only one mind can be known to exist) is coherent, contrary to your objection. — Michael

I guess I'll grant you this edge case (that there can be a last rational agent in the universe), but this is a mere crumb.

My primary point is that epistemological solipsism is incoherent as a claim about other minds in general, namely that they ought not just assume that such other minds exist.

I take this as a claim about the norms that apply to all rational agents, a claim about a world that transcends the claimant, one he could be wrong about. 'One ought not assume that there are others.'

Or, put it this way, 'one ought not assume there are norms.' Do norms make sense without a world in the most general sense to govern, potential/general agents to which they apply ?

I don't know why you think it would be a fantasy. Experiences are real, not made up. — Michael

I refer just to the usual, practical distinction of what seemed to be the case and what is the case. 'I thought I paid the rent, but that was just a dream.'

I don't see what grip we can give 'real' or 'experience' is there is just one blob of world-truth-experience-dream-reality-self. I can of course imagine a sole survivor. So the issue is the status of rationality, whether it makes sense for an inside without an outside to proclaim and justify norms.

I can talk about things that don't exist. Even if atheism is true I can talk about God, and if I claim that God exists then my claim is false. — Michael

Yes, granted. That's not the issue.

even (your) reliance on logic – normative rationality – presupposes selves-other-than-yourself (i.e. discursive community) — 180 Proof

:up:

I can be right or wrong about the world all by myself, thank you very much. — Mww

I don't dispute that rational agents can make true or false claims. Much of what we do (so runs the theory) is keep score on the noninferential claims and inferences of others. But I don't think the notion of a private language makes sense, so you are running pirated software, sir. Do we not bark and hiss in these inherited norm-governed, sound patterns known as English ?

ven if I'm the last (or first) man alive, the various axioms and rules of inference hold. The law of noncontradiction doesn't just fade away in a nuclear holocaust where I'm the only survivor. — Michael

I think this leans on psychologism, as if logic were mere facts about human cognition and not normative, a thesis that can only be established if it is false.

We've found where the boot pinches. The essence of my position is that rationality is normative, implicitly about a world beyond the philosopher. "One (in general, as a rational agent) ought not to assume that there is a world one can be wrong about...or a world beyond one to which norms apply."

My primary point is that epistemological solipsism is incoherent as a claim about other minds in general, namely that they ought not just assume that such other minds exist. — Pie

The epistemological solipsist says that one cannot know that there are other minds, he doesn't say anything about what one should or should not assume.

I can't know that I won't die tomorrow, but I'm going to assume and live as if I won't.

In fact, assumptions entail skepticism. If I knew something then it wouldn't be an assumption.