When W says that solipsism is not an opinion, the view is connected to the Tractatus saying it is present but cannot be said. There is something to be overcome but is not like overturning a proposition.

When W says that solipsism is not an opinion, the view is connected to the Tractatus saying it is present but cannot be said. There is something to be overcome but is not like overturning a proposition. — Paine

Yes, of course there must be a connection. That's very tricky. One might have expected W to announce that he had changed his mind, or not, and here's why. But, as usual, there's no explicit reference to the Tractatus. I suppose one question is whether W has overcome the solipsism of the TLP or is just expressing it in a different way. I think the orthodox view is that he has overcome it, in the sense that he does not even pick up the TLP discussion - not would it make much sense, I think, without the framework of logical atomism. To be honest, I don't know what I think. Thank you for that.
A possible preliminary question is whether W stands by solipsism “strictly carried out coincides with pure realism” (5.64). I can't see an analogy with that remark in what he says here. Nor does he even mention the limits of the world.

It is very tricky. I am inclined to think that it is not overcome but I won't try to argue for that as a thesis but just give some impressions on a field of uncertainty.

The solipsism of TLP appears as a natural consequence of the previous statements but accepting that result is not a speaking of it. It sounds like a speaking of it. We need a point of comparison to approach this negative.

The reference to the condition of being "realist" is connected in my mind to 6.431:

So too the world doesn't change when we die, it just ends.

This suggests that Berkeley not "carrying out" the thought allowed him to have opinions about what is objective that is a misunderstanding of his transcendental place, to employ a Kantian term. Wittgenstein insists that we are constrained in this regard. That restraint is also evident in his later work. For example:

240. Disputes do not break out (among mathematicians, say) over the question whether a rule has been obeyed or not. People don't come to blows over it, for example. That is part of the framework on which the working of our language is based (for example, in giving descriptions).

241. "So you are saying that human agreement decides what is true and what is false?"—It is what human beings say that is true and false; and they agree in the language they use. That is no agreement in opinions but in form of life. — Philosophical Investigations

There is also all the emphasis on what is private or not in the context of language. I will leave it there.

The first issue is to get him puzzled, to get him to see that his resolution is not a solution. Or, it is we who feel unhappy with his conclusion. So, in a way, all we are doing - all we can ever do - is to develop an untangling - an alternative view, and then, perhaps, persuade him of it. — Ludwig V

But if you remember on p.6, the solipsist/skeptic were already in a “muddle” that they turned into a problem so that they could have it be something to solve (to find an “answer”). “How do I know you are in pain?” So it is not just untangling the solution, but reversing the framing of it as a problem/puzzle in the first place. I would offer that the “source” of their puzzlement is in a sense themselves. Witt starts by saying they mistakenly picture thoughts as objects, and that they are forced into befuddlement by the analogy, but it’s from a “temptation” to chose “objects” as analogous, and I offer it’s because they want the same things from thoughts that they have with objects, like a direct relationship, something verifiable, measurable, predictable, generalizable, independent, etc., i.e. “object”-tive.

If that is the case, then his method, of showing other senses of the same expressions/propositions, is not to show them they are “wrong” or are being obtuse, but for them to see that their solution simply can’t do what they want it to—to know/or not know the other for certain, objectively (at least not without circumstances like conjoined twins)—it can’t satisfy their desire, their intellectual requirement. And perhaps it’s not just a desire for objectivity, but also a fear, a truth they are unwilling to accept: that you and I just have separate bodies, and we are thus responsible for the work (back and forth) to bridge that gap. The reluctance to give up claiming impossibility is the fear of being known, possibly entirely, because we may not have the depth (or difference) they wanted to hold on to as inherent (as different from you as a bat).

Now I know @Ludwig V might worry the difference between the “psychological” and logical, or others might say I’ve changed the issue to feelings, but Witt talks about the mindset of the skeptic (tempted, dissatisfied, puzzled). I am not attributing motives as necessary, but from the categorical error (anthropomorphizing the logical mistake) because we are not just talking about a “philosophical” issue, but our basic human response to others. The skeptic claims the same dominion, only limiting it to the intellectual, which is (though unaware) by design, and the whole problem.

Why would the solipsist ask that question? — Ludwig V

I think it is similar to getting sucked into asking how we could destroy red (p.31) or what the absence of thought would look like (or maybe a thought about nothing; can’t remember where that was) because we got stuck on a framework with color as a quality and thought as an object (then how: an object of nothing?). But I could barely get there.

To me, this reads as his response to the Oxford ordinary language philosophers. — Ludwig V

Wisdom, yes, and Hume; to say “of course that’s a table, duh”, not trying to understand the “difficulty”, not seeing there is perhaps something to learn from/by the skeptic.

I have no idea what this [negation discussion] is referring to. — Ludwig V

No idea. There is mention of imagining a substantive (object) for time would make it understandable how there might be a deity of negation (p.6). But I know more understand that, then the reference here, nor negation itself really.

The solipsism of TLP appears as a natural consequence of the previous statements but accepting that result is not a speaking of it. It sounds like a speaking of it. We need a point of comparison to approach this negative. — Paine

Not sure I understand the last sentence. There is a very tricky problem, though, in working out how one can state a philosophical thesis without relapsing into nonsense - because, in the standard account - one is working on the borderline between sense and nonsense. The latter is not an assertion and therefore cannot be denied, or contradicted. For example, strictly speaking, it is performatively self-contradictory to assert solipsism as an assertion addressed to someone else.
The stuff about my world vs the real world tracks back to Berkeley's realization that he doesn't have an idea of himself, because his perceiving self is not among the things (ideas) that he perceives. (So he postulates that he has a "notion" of himself instead.) Lichtenberg, I believe, a little later comes up with the objection to Descartes' cogito that it goes further than it should because it includes the doubter in what is immediately known, but the doubter is not an element of the thinking - and indeed is not subject to doubt.
In the TLP, the world is everything that is the case - facts or states of affairs, not objects. The world is described by the totality of states of affairs that can be described in a language., My world, presumably, is all the states of affairs that I am aware of. Common-sensically, then, my world is a subset of the world. But if solipsism is true, the distinction between my world and the real world collapses - my world and the world overlap completely. The list of propositions that describe my world is identical with the list of propositions that describe the world. So where one might describe a state of affairs in the real world with "The cat is on the mat" and in my world as "I know that the cat is on the mat", in a solipsistic world there is no difference between the two states of affairs. "I know ..." adds nothing to the report - and indeed is not meaningful in real-world-speak (because "I" doesn't designate an object in the world). One needs multiple "I"'s to articulate the concept of one's own self.

I hope that makes some sense. The relevant point I'm after is that one cannot give a clear sense to solipsism in an ordinary language.

This suggests that Berkeley not "carrying out" the thought allowed him to have opinions about what is objective that is a misunderstanding of his transcendental place, to employ a Kantian term. Wittgenstein insists that we are constrained in this regard. That restraint is also evident in his later work. — Paine

Well, I can see that Berkeley did not understand the point he was making when he introduced the concept of the perceiver as essential to the perception but additional to it. It is true, I think, that the connection between the TLP and the Blue Book is the continuing struggle to clarify just what it is that the solipsist is trying to assert.

Disputes do not break out (among mathematicians, say) over the question whether a rule has been obeyed or not. People don't come to blows over it, for example. That is part of the framework on which the working of our language is based (for example, in giving descriptions). — Philosophical Investigations 240

Few people would quarrel with that. I am, let us say, a bit queasy about the first sentence. Disputes like that break out quite often - his own argument with (about) Godel is an example. But that doctrine is indeed a lynch-pin in orthodox philosophy. Yet, later on, the distinction between grammatical statements and others gets serious eroded and transformed into different uses of particular grammatical (linguistic) forms.

"So you are saying that human agreement decides what is true and what is false?" —It is what human beings say that is true and false; and they agree in the language they use. That is no agreement in opinions but in form of life. — Philosophical Investigations 241

An excellent quotation. People make that mistake a lot. I must remember that for future use.

Privacy is indeed another issue.

Your summary of Berkeley and his reception is helpful and germane.

I would only add that the "world ending" in 6.431 is a recognition of the solitary that reveals the Berkeleyan move to be a giving oneself a world before retreating from it. When not permitted the move, one cannot judge objectivity from a separate space. That is an echo of PI 251:

These words are a defence against something whose form makes it look like an empirical proposition but which is really a grammatical one.

When not permitted the move, one cannot judge objectivity from a separate space. — Paine

That's complicated. This argument is not like others - the length of a rod, say. It's about the limits of language. We have to explore them in devious ways. I can envisage an argument that solipsism might provide opportunities for understanding those limits that are not available without playing with nonsense.

Wisdom, yes, and Hume; to say “of course that’s a table, duh”, not trying to understand the “difficulty”, not seeing there is perhaps something to learn from/by the skeptic. — Antony Nickles

Hume is very explicit about the difference between radical scepticism, which he identifies as Pyrrhonism or academic scepticism. That, he thinks, cannot be refuted, but must be cured by immersion in real life. On the other hand, he thinks that "judicious" scepticism and "necessary for the conduct of affairs".

So it is not just untangling the solution, but reversing the framing of it as a problem/puzzle in the first place. — Antony Nickles

It's very hard to produce a concise statement of exactly what is going on. Seeing the puzzle as a puzzle is an interpretation. Seeing it as not a puzzle is another. The duck-rabbit again.

Witt starts by saying they mistakenly picture thoughts as objects, and that they are forced into befuddlement by the analogy, but it’s from a “temptation” to chose “objects” as analogous, and I offer it’s because they want the same things from thoughts that they have with objects, like a direct relationship, something verifiable, measurable, predictable, generalizable, independent, etc., i.e. “object”-tive. — Antony Nickles

I agree that reification is endemic in philosophy and likely the commonest example of the mistake of applying one's model in inappropriate circumstances. Here's another example of what I consider to be the same thought.

It is the mark of an educated man to look for precision in each class of things just so far as the nature of the subject admits; it is evidently equally foolish to accept probable reasoning from a mathematician and to demand from a rhetorician scientific proofs. — Nicomachean Ethics Book I, 1094b.24

we are not just talking about a “philosophical” issue, but our basic human response to others. The skeptic claims the same dominion, only limiting it to the intellectual, which is (though unaware) by design, and the whole problem. — Antony Nickles

On the other hand, the field of philosophy is often described as logic - and that makes sense to me in the extended sense of logic that applies to Wittgenstein's work. Basic human responses does not exclude logic, I suppose, but does call up a field that is, perhaps, more closely related to psychology or even biology - instincts, for example, could count as basic human responses. I don't want to be caught out trying to imprison philosophy within any very specific boundaries. But there's a certain vagueness here that, as you put it, I'm uneasy with.
I do agree that one effect of W's work is to make us aware of the limitations, for philosophy, of a purely theoretical perspective - especially when it becomes dogmatic about what it and isn't philosophy.

When not permitted the move, one cannot judge objectivity from a separate space. — Paine

I can envisage an argument that solipsism might provide opportunities for understanding those limits that are not available without playing with nonsense. — Ludwig V

I was giving a reading of what the "ending of the world" might mean in Wittgenstein's argument. not arguing for it on my own behalf.

@Ludwig V @Paine

Section 18 - the unidentifiable individual (p.61-65)

At first, I take his “considering the criteria for the identity of a person” (p.61) as more about ‘essence’ and grammar (criteria). He says that we could and might identify someone entirely differently if circumstances changed making certain characteristics more prevalent or useful, implying there is not an underlying, determinate identity. “We can say whichever we like [that Jekyll and Hyde are one or two people]. We are not forced to talk of a double personality.” (p.62) He even throws away that there is a “right” or “wrong” about identity. The “inheritance” and “preservation” of what is meaningful is “at liberty” and without one “legitimacy”, as, by analogy, circumstances shift under our (say, math) terms over time, becoming meaningful for entirely different reasons.

I take the point as: how society ended up with the criteria for judgments that we have is not only contingent on how our world rolls (our history of circumstances). The fact that we do, or could, have multiple ways of judging something shows that we also have an interest (or multiple) in doing it the way we do. The “usage” is connected to those (cultural) interests in something, reflected in the criteria to identify that use.

He next considers the idea that ‘seeing’ is a continuous part of who ‘we’ are; that it is essential and ever-present (as people take Descartes to want from thinking). Logically, this would mean that every instance of seeing would have something in common, which he narrows down to “the experience of seeing itself” (p.63), which I read as distinguishing nothing (“pointing… not at anything in [ the visual field ]” (p.64)), and thus wishful rather than meaningful to point out.

The difference between a physical object and what we ‘see’ are not different types of objects, as a railroad law is not a railroad track (one is an idea). I take this to mean that what we are trying to do, in ‘seeing’ something, is not in the same category (“kind”) as our relationship with physical objects (equated with knowledge). Our interests differ for each. Some examples would be that we are pointing something out to you when we ‘see’ something; or we are evaluating it, say, seeing it’s potential; or interpreting it as… (PI #74), say, a box to step on or a container.

So he finally gets to our interest in only wanting what I see to be ‘real’, which is to keep part of me for myself, in reserve, impossible to be fully known or limited, read, characterized, labeled. To hold “what I mean” (p.65) as unable to be fully understood is to wish for the implications and connotations of our expressions to be ultimately under my control, judged as met or meant by me, to always allow me the last word, as if there was an essence of what I say that is “information” that the other lacks because it is mysterious, hidden, private… me.

I would only add that the "world ending" in 6.431 is a recognition of the solitary that reveals the Berkeleyan move to be a giving oneself a world before retreating from it. When not permitted the move, one cannot judge objectivity from a separate space. That is an echo of PI 251: — Paine

I don't really understand 6.431. I can see that death is the limit (end) of life and consequently not an even in life (he says that somewhere in the book, doesn't he?). Consequently death is not the destruction of my world because that destruction would be part of my life. But he seems to be saying that my death is the end of the world. That would be true of the solipsist's world, But not of anybody else's.
But what is the Berkeleyan move, exactly? The move that insists that it is only our own minds that we perceive and that consequently exists? in what way does he retreat from that? Or do you mean that he posits the world as the ideas of God, but allows God to remain hidden behind those ideas? (I could make sense of the idea that Kant does this, by giving himself the phenomena, but then positing the hidden reality of the noumena or being-in-itself.)

a “temptation” to chose “objects” as analogous, and I offer it’s because they want the same things from thoughts that they have with objects, like a direct relationship, something verifiable, measurable, predictable, generalizable, independent, etc., i.e. “object”-tive. — Antony Nickles

Yes, I notice that you are also suggesting quite a wide range of possible needs in the next paragraph as well. All good grist for the mill of reflection. Thanks.
A small contribution from me. Scepticism is often explained as a desire for certainty, but if certainty is an unattainable ideal, perhaps we should think of it as being, not the desire for certainty, but the fear of it, as some inflexible that hems us in.

I'll come back later when I've read your latest carefully and the relevant extract.

A small contribution from me. Scepticism is often explained as a desire for certainty, but if certainty is an unattainable ideal, perhaps we should think of it as being, not the desire for certainty, but the fear of it, as some inflexible that hems us in. — Ludwig V

If we may equate skepticism with doubt, then…

“A doubt that doubted everything would not be a doubt” “The game of doubting itself presupposes certainty.”
(On Certainty)

@Paine

Scepticism is often explained as a desire for certainty, but if certainty is an unattainable ideal, perhaps we should think of it as being, not the desire for certainty, but the fear of it, as some inflexible that hems us in. — Ludwig V

Obviously I’d like to stay on topic (understanding this text), or at least until we get to the end (only 10 pages left), after which we will of course open it up to discuss these themes in larger contexts. But I think we can address this in the ballpark of the topics of the book. In understanding ‘certainty’ as a term we could apply here, it would be the framework imposed by the analogy of our relation to objects. In the PI it is the ideal of a pure logic, like math, and On Certainty is its own beast, but @Ludwig V has a point, which is the flip-side of what Witt takes up in the last section (being unknowable). If we have/are something ‘certain’, we keep something, but if language is ‘certain’, like equating ‘meaning’, as an object, with the world as something static (meaning as only labels), then we might object (fear) that I am trapped by my ‘self’, not only for me, but that I am completely ‘knowable’ to others in my entirety, as unguarded myself and through what I say—not just wedded to it, but only to it, constrained within it. Thank you for your patience with the reading.

Are you asking me to not comment with references to earlier and later work by W until you finish going through the text?

My focus has been on the discussion of solipsism in the Blue Book and why W says it is not an opinion. I don't see the issue of certainty as germane to my observations.

But I will refrain if that is your preference.

Thank you for your patience with the reading. — Antony Nickles

It's a question of balance. I didn't think that my observation would be a distraction in the sense of getting in the way of the reading.

If we may equate skepticism with doubt, then… — Joshs

Yes, that's a good reply. One might want to argue about whether it is conclusive on its own. But that wasn't quite what I was talking about. It was, rather, Wittgenstein's comments about "our real need" or the what motivates, for example, the sceptic. Why would anyone say that they were the only person in existence? I think we need to tease out what, exactly, that means.

In understanding ‘certainty’ as a term we could apply here, it would be the framework imposed by the analogy of our relation to objects. — Antony Nickles

Yes, that's the context. I was just a bit concerned that sometimes people seem to think that the only problem is reification, and I think that could become a source of cramp.

we might object (fear) that I am trapped by my ‘self’, — Antony Nickles

I have seen people refer to being caged in the self, in the context of solipsism.

If we may equate skepticism with doubt, then…
— Joshs
Yes, that's a good reply. One might want to argue about whether it is conclusive on its own. But that wasn't quite what I was talking about. It was, rather, Wittgenstein's comments about "our real need" or the what motivates, for example, the sceptic. Why would anyone say that they were the only person in existence? I think we need to tease out what, exactly, that means? — Ludwig V

You were right to point out that in the context of the reading, the kind of certainty that scepticism is a response to is that associated with knowledge of a picture. And yet the sceptic isnt able to dissolve the confusion arising from the separation of meaning from expression. For the sceptic , the idealist cant know what they claim to know. But an examination of the grammar of a solipsist statement like ‘it is only I who see’ reveals not whether something can or cannot be meant, but HOW it is meant, thereby avoiding both idealist certainty and scepticism.

Logically, this would mean that every instance of seeing would have something in common, which he narrows down to “the experience of seeing itself” (p.63), which I read as distinguishing nothing (“pointing… not at anything in [ the visual field ]” (p.64)), and thus wishful rather than meaningful to point out. — Antony Nickles

Well, he is quite right. There is a territory that, so far as I know, he does not explore. I point at a bus, and say (in grammatical mode) “That’s a bus”. The self-same gesture, in a different context could count as a definition of “red”. It’s not really a question of my intention being different. It’s that my audience needs to understand what kind of object a bus or a colour is, before they can interpret my definition.
In one way, one cannot point to one’s visual field – only to objects in it. To understand the gesture that W is talking about, we have to think about how we realize that we have a visual field, that is, we have to understand what kind of thing a visual field is. Whether that understanding would coincide with what the solipsist is trying to say is another question.

To hold “what I mean” (p.65) as unable to be fully understood is to wish for the implications and connotations of our expressions to be ultimately under my control, judged as met or meant by me, — Antony Nickles

Yes. But it could also be that I do not wish to be caged in the implicatons and connotations of our expressions.
I would be happy to say that we never “fully understand” things, even if we can understand them sufficiently for the purposes in hand. That is, that the phrase “fully understand” (which, presumably, contrasts with “partly understand) has not been given a coherent meaning.

What he said really recommended his notation, in the sense in which a notation can be recommended. — p.60

I can think of cases where a notation might recommend itself - for the most part on pragmatic grounds. Whether they are relevant to philosophy is not clear to me. I think we think that because any notation must conform to the same logic, the difference between notations will not be significant.

We are inclined to use personal names in the way we do, only as a consequence of these facts. — p.61

This, of course, radically changes how we need to think of analytic vs synthetic. The consequences are not at all clear to me. I think we need some distinction along those lines. (My next quotation suggests that W agrees).

But I wish it to be logically impossible that he should understand me, that is to say, it should be meaningless, not false, to say that he understands me. Thus my expression is one of the many which is used on various occasions by philosophers and supposed to convey something to the person who says it, though essentially incapable of conveying anything to anyone else. — p.65

But when W talks of understanding the solipsist, rather than merely refuting him, he suggests that we should be asking what they are trying to convey. His discussion in these pages illustrates how that might go, and be reduced to a difference of notation.

It would be wrong to say that when someone points to the sun with his hand, he is pointing both to the sun and himself because it is he who points; on the other hand, he may by pointing attract attention both to the sun and to himself. — p.66

This goes back to the question how we can point to a visual field.

But an examination of the grammar of a solipsist statement like ‘it is only I who see’ reveals not whether something can or cannot be meant, but HOW it is meant, thereby avoiding both idealist certainty and scepticism. — Joshs

But doesn't he also claim that what the solipsist want to say, or mean, is incoherent or perhaps just a question of notation. You make me realize that I'm actually quite confused about exactly what is going on here.

@Ludwig V

My focus has been on the discussion of solipsism in the Blue Book and why W says it is not an opinion. I don't see the issue of certainty as germane to my observations. — Paine

Ah, my mistake; I lost the trail (from p.60). The “opinion” reference is obviously germane. I take it up here (though, of course, there is no obligation to address that). And to answer your question on the discussion: yes, we are pointing to/contrasting, etc. any corresponding mention of terms/discussions in other texts. I only mentioned it as we are of course primarily trying to understand how this text considers them. All that is just to say that I’m having a hard time understanding even what this text is saying (internally).

The solipsist who says ‘only I feel real pain’, ‘only I really see (or hear)’ is not stating an opinion; and that's why he is so sure of what he says. — (p.60)

For example, the text of the quote and its place in the surrounding train of thought seems to beg some questions (all of which I state rhetorically, simply to show the depth of his esotericism, and not to dismiss anyone else’s interests in the matter). Foremost, if not an “opinion”, what? or is it that the solipsist is not “stating” an opinion? (Or both) and then what is the alternative act? and form? Does their “being so sure” have anything to do with their being “irresistibly tempted”? (just below) or, if “so sure” is not being ‘certain’—like knowledge of a fact as if a math-like equation—what constitutes this surety? i.e., why/how “so” sure?

In that vein, the act they are doing (besides “stating an opinion”) is described by negation (in the paragraph above) in that “[ in not stating an opinion, they do ] not thereby disagree with us about any practical question of fact” i.e., we agree on the facts, so their claim is not that what they are saying is actually the correct fact of the matter. Thus, logically, what they are saying is not a factual claim in opposition to: ‘I am not the only one to feel (real) pain’; or, ‘others feel pain, and theirs is as “real” as mine’. If what they are saying is not opinion nor fact, then what are they doing (in what they are saying)? and how is not being a claim to knowledge “why” they are “so sure”? (a compulsion? a conviction?)

Another part any answers I would think have to include is that, even though “not stating an opinion”, they still want to “restrict” what is referred to as “‘real’” (and so how, if not restricted factually?). Methodologically Witt would take the fact to which he claims we both agree—about only my pain being “real”—and give examples of usages of “real” other than what gives the solipsist what they want (what I read, in Sec 18, as the desire to be unknowable). As I said in my reading of this quote above, these could be “real” as in: not possibly manufactured; not (necessarily) over-exaggerated as someone could; contained, in feeling the pain but not having to be responded to, as another’s are by me.

When W says that solipsism is not an opinion, the view is connected to the Tractatus saying it is present but cannot be said. There is something to be overcome but it is not like overturning a proposition. — Paine

I do think [ responding to the quote, that ] Wittgenstein is looking for a way to help the solipsist find an answer to a problem — Paine

Not an opinion: present, not proposed; problematic though not to be overturned, but answered by overcoming. I would guess this is referring to the “irresistible temptation”, but I am not familiar enough with the Tractatus to be sure in relation to the reference to that and the subsequent discussion. Any chance any of what I said is close? or at least the text here is related in some way?

We want to understand “the source of his puzzlement”(p.59), in order to “have answered his difficulty” (p.58). — Antony Nickles

In considering the solipsist, I think it is important to keep the "realist" and
"idealist" within shooting range.

Does a realist pity me more than an idealist or a solipsist? – In fact the solipsist asks: “How can we believe that the other has pain; what does it mean to believe this? How can the expression of such a supposition make sense? — Blue Book, page 74, internet edition

They each are found to "draw some misleading analogy" of the kind discussed on page 73. The discussion down through page 75 has the realists lacking what solipsist does not have. They hold up opposite ends of the same "grammatical difficulty."

The same group is assembled again a few pages later:

I shall try to elucidate the problem discussed by realists, idealists, and solipsists by showing you a problem closely related to it. — ibid 86

The point of the example is to demonstrate:

To say that a word is used in two (or more) different ways does in itself not yet give us any idea about its use. It only specifies a way of looking at this usage. — ibid 87

A condensed version of the above can be found at PI 402.

The problems of talking about "the world as resting upon personal experience" at page 73 began this comparison of theories, but the problems go back to the beginning of how to understand thinking as being in a location. The solipsist "not stating an opinion" goes back to different ways a reason is given:

Let us go back to the statement that thinking essentially consists in operating with signs. My point was that it is liable to mislead us if we say thinking is a mental activity. The question what kind of an activity thinking is is analogous to this: “Where does thinking take place?” We can answer: on paper, in our head, in the mind. None of these statements of locality gives the locality of thinking. The use of all these specifications is correct but we must not be misled by the similarity of their linguistic forms into a false conception of their grammar. As, e.g., when you say: “Surely, the real place of thought is in our head”. The same applies to the idea of thinking as an activity. It is correct to say that thinking is an activity of our writing hand, of our larynx, of our head, and of our mind, so long as we understand the grammar of these statements. And it is, furthermore, extremely important to realize how by misunderstanding the grammar of our expressions, we are led to think of one in particular of these statements as giving the real seat of the activity of thinking. — ibid. page 26

If the solipsist was stating an opinion, the other views would be conceivable, which he denies.

I will make my comments about TLP in a reply to

@Antony Nickles

In considering the solipsist, I think it is important to keep the "realist" and
"idealist" within shooting range. — Paine

I agree with that. They can all be seen as alternative views of the same issues - temptations.
Given that we (sort of) understand the difference between solispsist and realist, what are we to make of the distinction between solipsist and idealist?
Berkeley is clear that he believes in the existence of people other than himself. He believes that on the grounds of their effects - presumable on his ideas, the objects of immediate perception - where there is no such thing as mediated perception. He needs this premiss because he wants to argue that the world as we perceive it is caused by God. I can't see that there is any hope of consistency here, except in solipsism. So I think that idealism collapses into solipsism.

The distinctive contribution of Wittgenstein is the question of limits of the world.

And it is, furthermore, extremely important to realize how by misunderstanding the grammar of our expressions, we are led to think of one in particular of these statements as giving the real seat of the activity of thinking. — ibid. page 26

If the solipist was stating an opinion, the other views would be conceivable, which he denies. — Paine

We don't necessarily have to agree with him. Ryle has a good deal to say about thinking; in the end, as I remember it, he seems to give up. He slaps a label ("polymorphous") on it and leaves it at that. But I'm led to think that the range and confusion of the possible seats of thinking may be meant to get us to see that the debate about experience simply can't be tidied up into a structure of alternatives. (As well as understanding that the question where thinking is, or (better) what it consists of is not sufficiently articulated to be answerable.) Then we might be able to talk about holding one view (opinion) or another. But the solipsist's view of experience is part of the range of thinking and the solipsist's view is not special, except that we are tempted to hang on to it because it seems to be somehow above the fray.

Does any of that make sense?

I don't want to lose the momentum of making progress through the text. In any case, it seems to me that these last pages are germane to our discussion. Am I right to think that we have got to p. 65?

I didn't think that my observation would be a distraction — Ludwig V

I think I just didn’t see the original connection @Paine was making to the “opinion” issue, so I took the rest as just an unrelated discussion of the TLP.

that destruction would be part of my life — Ludwig V

Perhaps in claiming that only what the solipsist sees/feels, etc. is real (as if “alive”), they are thus “destroying” the world (by cutting it off/“killing” it), before it disappoints them.

the Berkeleyan move… [of] giving oneself a world before retreating from it. — Paine

Where @Ludwig V’s mind goes to the world we create in lieu of the thing-in-itself, my thought went to the related but opposite side where we imagine (“give” ourselves, as I take @Paine to put it) a ‘real’ world, but then we manufacture the idea of a (“peculiar” Witt says) mechanism, say, of ‘perception’, that only allows us an ‘appearance’ of that world, letting us “retreat” to arms length behind knowledge (or a lack of it), to avoid risking our hands getting dirty (to account for the mistakes we would make in a way that gives us a feeling of control).

These words [ ‘I can't imagine the opposite’ ] are a defence against something whose form makes it look like an empirical proposition but which is really a grammatical one. PI #251

Not to try to sort all of this out, but, for our purposes, it is interesting that he is claiming that the grammatical sense is ‘real’, and that the same proposition just looks like an empirical one. There is something to that in trying to persuade the skeptic, like: revealing the illusion of its empirical sense, but we know it can’t be a factual dispute, as the skeptic already acknowledges that their “fact”, say, of “me” as an object, is unverifiable, and the rest they grant as common sense, which they then just demote in its entirety as not in the class (of certainty) that philosophy sees or provides. Perhaps it is the logical impossibility (the “can’t”). Here, of not being able to imagine an opposite, or some other exercise, that defends against the temptation to see a claim as empirical.

@Paine

But I'm led to think that the range and confusion of the possible seats of thinking may be meant to get us to see that the debate about experience simply can't be tidied up into a structure of alternatives. — Ludwig V

In saying that thinking can be in all those “locations” I take it just to say there is associated logic to thinking in each case. The confusion is from imagining thinking as a mechanism and not an activity (conducted by the hand, our speech, our ‘mind’). If we aren’t fixated on a mechanism of thought, then there is no ‘seat” or ‘location” of thinking (nor where a thought as an object would be). It dawned on me the other day that thought does not consist of a substance, but a judgment. “They are thinking (it through)”, “They are not thinking (but just reacting impulsively), “See that squirrel thinking about how to get the seeds out of that bird feeder.” It consists of acts (writing, speaking, internal monologue, problem solving, brain storming, just mulling it over) that meet certain criteria (not about the result, but compared to parroting, expressing, performing, etc.).

And if we are not picturing ‘experience’ also as a mechanism or “structure”, but, logically, I would offer that it is the description of a distinction, an event out of the ordinary, and not in some sense of: everything all the time that is “my experience”. As I may have said, sometimes going to the grocery store is not an experience.

And yes, p. 65, paragraph starting: “The meaning of a phrase for us is characterized…”

Perhaps in claiming that only what the solipsist sees/feels, etc. is real (as if “alive”), they are thus “destroying” the world (by cutting it off/“killing” it), before it disappoints them.

the Berkeleyan move… [of] giving oneself a world before retreating from it.
— Paine

Where Ludwig V’s mind goes to the world we create in lieu of the thing-in-itself, my thought went to the related but opposite side where we imagine (“give” ourselves, as I take @Paine to put it) a ‘real’ world, but then we manufacture the idea of a (“peculiar” Witt says) mechanism, say, of ‘perception’, that only allows us an ‘appearance’ of that world, letting us “retreat” to arms length behind knowledge (or a lack of it), to avoid risking our hands getting dirty (to account for the mistakes we would make in a way that gives us a feeling of control). — Antony Nickles

When I ask myself how Wittgenstein understands the motivation associated with seeing the world as a solipsist, realist or idealist, I’m led to the terms he often uses; being ‘captivated’or ‘tempted’ by a picture. The impression I get is that it is the bewitching grammar of language itself that motivates our confusions, not something that could be misread as an inner psychological motive, like a desire to avoid disappointment, a desire for control or to avoid getting our hands dirty. Solipsism is the result of an intellectual cramp, not a psychological flaw

I can't see that there is any hope of consistency here, except in solipsism. So I think that idealism collapses into solipsism. — Ludwig V

I think W is looking at Kant as the champion of idealism rather than Berkeley. The erosion of Kant's foundation is the work of the Blue Book from its beginning. While introducing the life of signs as use, the following mistake is made:

The mistake we are liable to make could be expressed thus: We are looking for the use of a sign, but we look for it as though it were an object co-existing with the sign. (One of the reasons for this mistake is again that we are looking for a “thing corresponding to a substantive.”) — BB, 9, internet edition

That establishes how W uses "occult" but also points to how objects co-exist with their representations in Kant.

While seeking how the rules for signs emerge, two scenarios are depicted:

In so far as the teaching brings about the association, feeling of recognition, etc. etc., it is the cause of the phenomena of understanding, obeying, etc.; and it is a hypothesis that the process of teaching should be needed in order to bring about these effects. It is conceivable, in this sense, that all the processes of understanding, obeying, etc. should have happened without the person ever having been taught the language. (This, just now, seems extremely paradoxical).

B. The teaching may have supplied us with a rule which is itself involved in the processes of understanding, obeying, etc.; “involved”, however, meaning that the expression of this rule forms
part of these processes.
We must distinguish between what one might call a “process being in accordance with a rule”, and, “a process involving a rule” (in the above sense). — ibid. page 21

The language of "possibility of experience" cannot be cleanly divided between sensibility and understanding in this scenario. The way we speak of reason as our capacity is a model rather than an experience itself.

The proposition, that your action has such-and-such a cause, is a hypothesis. The hypothesis is well-founded if one has had a number of experiences which, roughly speaking, agree in showing that your action is the regular sequel of certain conditions which we then call causes of the action. In order to know the reason which you had for making a certain statement, for acting in a particular way, etc., no number of agreeing experiences is necessary, and the statement of your reason is not a hypothesis. The difference between the grammars of “reason” and “cause” is quite similar to that between the grammars of “motive” and “cause”. Of the cause one can say that one can’t know it but one can only conjecture it. On the other hand one often says: “Surely I must know why I did it” talking of the motive. When I say: “we can only conjecture the cause but we know the motive” this statement will be seen later on to be a grammatical one. The “can” refers to a logical possibility.

The double use of the word “why”, asking for the cause and asking for the motive, together with the idea that we can know, and not only conjecture, our motives, gives rise to the confusion that a motive is a cause of which we are immediately aware, a cause “seen from the inside”, or a cause experienced. Giving a reason is like giving a calculation by which you have arrived at a certain result. — ibid. 25

This is a real thumb in the eye to Kant's Refutation of Idealism:

The mere, but empirically determined, consciousness of my own existence proves the existence of objects in space outside me. — CPR, B275

The difference between private experience and shared experience is not a demarcation of outer and inner. Since the Refutation is an argument against solipsism, it maintains its status as a particular model adjacent to the others.

Whoops

@Ludwig V @Paine

The impression I get is that it is the tricky grammar of language itself that motivates our confusions, not something that could be misread as an inner psychological motive, — Joshs

I’ve seen the term “psychological” used a few times now, and, since it does not appear to be used in reference to actual subconscious psychological forces (reenactment or displacement of trauma, insecurity, etc.), I can only assume it is being used as Witt does elsewhere, but I think that technical use is not appropriate to apply here. In this case, I’ll have to piece together the situation that is imagined and the implications that are imagined should follow, that it is not relevant.

One confusion I’ve seen is that it is seen as just personal, or just a belief only able to be defended by strong feelings, unable to be considered intellectually, logically. Related is the claim that philosophy does not or should not involve the “emotional”, but not actual feelings, because it’s just as a catch-all denigration to dismiss everything that does not meet a certain, predetermined requirement of rationality or logic.

But that flies in the face of Witt’s broadening the variable types of criteria we recognize for judgment which shows us that our human interests are reflected in (and part of) the logic of our practices. It is finding out why we predetermine and/or limit what criteria (interests) are valid and important that we have realized is at the heart of what we are investigating here. Also, as I mentioned to @Ludwig V here, I see the motivations and responses as also creating actual logical errors leading to philosophical misunderstandings, able to be resolved through philosophy.

And, yes!, the confusion inherent in the structure of language—not realizing that the things we say have multiple usages, partly because of the fact that words do have individual definitions outside of any context—and the leverage of analogy is how we impose and can get fixated on a certain picture. But that is the mechanism. Basically, we have still not answered (and I'd think you'd have to provide a reading different of) this: “He is irresistibly tempted to use a certain form of expression; but we must yet find why he is.”

It might help to acknowledge that, in their being a “why”, logically, there is a reason or motive, as: we chose our relation to objects as the analogy to impose, and there are reasons why we picked that--perhaps not all of them are intellectual, not all are apart from reasons of interest, even originating in instinctive responses to the basic logic of our situation to each other and the world.

You might say I’m projecting this, but there is evidence and references throughout the text. He does discuss disappointment (well actually, “dissatisfaction”**, but same enough) on p.58-59 (in my book, starting with “Now when the solipsist says that only his own experiences are real”). And he refers to what the skeptic “wants” (desires) “Thinking, one wants to say, is part of our 'private experience'.” (p.16) Or wishes for: “…describing the experience which we wish to call "observing thought in our brain"” (p.8) or “when we wish to give meaning to substantives to which no material objects correspond.” (p.36)

**I discuss the dissatisfaction with notation here in the 3rd paragraph.

t our human interests are reflected in (and part of) the logic of our practices. It is finding out why we predetermine and/or limit what criteria (interests) are valid and important that we have realized is at the heart of what we are investigating here. Also, as I mentioned to Ludwig V here, I see the motivations and responses as also creating actual logical errors leading to philosophical misunderstandings, able to be resolved through philosophy. — Antony Nickles

I think Witt understands motives as he understands meaning in general, as neither emanating from the subjective nor from the objective side , but as arising out of the interaction. Our interests are enacted in situations, out of which things strike us as funny , sad, boring or interesting in any unlimited variety of ways . When Wittgenstein uses terms like "dissatisfaction," "wants," and "wishes’ with respect to grammatical illusions, the want or wish is an expression of the intellectual disquiet caused by the grammatical picture. The picture's power is what causes the desire, rather than a pre-existing desire creating or contributing to the tendency to create grammatical illusions. In this sense, Wittgenstein treats motive similarly to the way Heidegger understands motivation.

One cannot construct being-in-the-world from willing, wishing, urge, and propensity as psychical acts. The desire for this conversation is determined by the task I have before me. This is the motive, the "for the sake of which". The determining factor is not an urge or a drive, driving and urging me from behind, but something standing before me, a task I am involved in, something I am charged with.”(Heidegger, Zollikon)

He proposes that one source is “when a notation dissatisfies us”. (p.59) .....We might want our (culture’s) interest in a thing to loosen, adjust, perhaps respond to general changes in the associated circumstances, perhaps for the recognition of a different “position” (“attitude” he says in the PI). — Antony Nickles

Yes, I think that's right. When it comes to notations, we're inclined to think that one notation should take care of every position/attitude or perspective. But actually, horses for courses suits us, in the world in which we live, will suit us better. But if the solipsist's doctrine is just another perspective (or interpretation), all we can do is to point out that it is inconvenient in some way. What we want (!) is a wy to dismiss, set aside, reject the doctrine - isn't it?

Perhaps in claiming that only what the solipsist sees/feels, etc. is real (as if “alive”), they are thus “destroying” the world (by cutting it off/“killing” it), before it disappoints them. — Antony Nickles

I've come to the conclusion that the solipsist has a point, but is making far too much of it. We should not just brush the whole thing under the philosphical carpet. For example, I like "alive" as a description of the difference between my experience and yours - from my perspective, and allowing that from your perspective, it is vice versa.

it is interesting that he is claiming that the grammatical sense is ‘real’, and that the same proposition just looks like an empirical one. — Antony Nickles

Well, a distinction between appearance and reality is one way of acknowledging something that the solipsist has got right, which enables us to focus on what they have got wrong.

If we aren’t fixated on a mechanism of thought, then there is no ‘seat” or ‘location” of thinking (nor where a thought as an object would be). It dawned on me the other day that thought does not consist of a substance, but a judgment. — Antony Nickles

Yes. The "what is...." question pushes us in the direction of looking for something that things consist of. But there isn't always anything. (Not just judgment, though, but a whole range of intellectual activities.) W doesn't note that there are some activities that count as thinking, such as calculating or writing or planning and preparing and other cases where the thinking is actually a construction to rationalize activities that do not count as thinking, but which only make sense if there is thought behind it, so to speak. I think we have to treat these as different, but related, language games.

And if we are not picturing ‘experience’ also as a mechanism or “structure”, but, logically, I would offer that it is the description of a distinction, an event out of the ordinary, and not in some sense of: everything all the time that is “my experience”. — Antony Nickles

Well, yes. But I'm not sure that those mundane activities which we barely notice could not be picked out as experiences under some circumstances. Do I notice picking up my keys as I leave the house or putting one foot in front of the other as I walk to the shops? Usually, I don't notice, but I can bring them to my attention if I need to. Sometimes, of course, the experience "forces" itself on us, as when I reach for my keys in my pocket and they are not there.

One confusion I’ve seen is that it is seen as just personal, or just a belief only able to be defended by strong feelings, unable to be considered intellectually, logically. Related is the claim that philosophy does not or should not involve the “emotional”, but not actual feelings, because it’s just as a catch-all denigration to dismiss everything that does not meet a certain, predetermined requirement of rationality or logic. — Antony Nickles

Yes. It's an illusion that philosophy is without passion.

But that flies in the face of Witt’s broadening the variable types of criteria we recognize for judgment which shows us that our human interests are reflected in (and part of) the logic of our practices. ...... I see the motivations and responses as also creating actual logical errors leading to philosophical misunderstandings, able to be resolved through philosophy. — Antony Nickles

"Finding out" sounds like something empirical. I think "making sense of" is more appropriate to philosophy. There's no problem about motivations and responses creating logical errors.

Basically, we have still not answered (and I'd think you'd have to provide a reading different of) this: “He is irresistibly tempted to use a certain form of expression; but we must yet find why he is.” — Antony Nickles

Yes. But this finding out is not the kind of finding out you are doing when you ask people why they are adopting a philosophical position. In philosophy, we are looking for arguments, not expressions of personal preference.

we chose our relation to objects as the analogy to impose, and there are reasons why we picked that--perhaps not all of them are intellectual, not all are apart from reasons of interest, even originating in instinctive responses — Antony Nickles

"Chose" may not be quite the right word in some cases.

I think W is looking at Kant as the champion of idealism rather than Berkeley. The erosion of Kant's foundation is the work of the Blue Book from its beginning. While introducing the life of signs as use, the following mistake is made:
"The mistake we are liable to make could be expressed thus: We are looking for the use of a sign, but we look for it as though it were an object co-existing with the sign. (One of the reasons for this mistake is again that we are looking for a “thing corresponding to a substantive.”) — BB, 9, internet edition
That establishes how W uses "occult" but also points to how objects co-exist with their representations in Kant. — Paine

Forgive me, I'm a bit confused. Is the mistake that you say is made in the following quotation. That is, do you agree with W that it is a mistake to look for the use of a sign as though it were an object co-existing with the sign. Again, since the word "occult" doesn't occur in the quoted passage, I'm not clear how it establishes how W uses it.
Again, I don't know enough to see how W is eroding Kant's foundation. A bit more explanation would help.

This is a real thumb in the eye to Kant's Refutation of Idealism:
The mere, but empirically determined, consciousness of my own existence proves the existence of objects in space outside me.
— CPR, B275
The difference between private experience and shared experience is not a demarcation of outer and inner. Since the Refutation is an argument against solipsism, it maintains its status as a particular model adjacent to the others. — Paine

There must be something wrong with me. Is the thumb in the eye in the previous quotation from BB? That quotation is all very well, but I don't see the relevance to the refutation of idealism. I take your point about outer and inner (which are pretty clearly metaphorical anyway. I can see an argument that my recognition of my own transcendental, geometrical POV proves the existence of space and time, since a POV (in our world) necessarily implies a viewer to view the view.

Solipsism is the result of an intellectual cramp, not a psychological flaw — Joshs

I wouldn't deny that psychological flaws might be part of the explanation why people make some intellectual choices. What I'm fishing for is a distinction between what explanations we can expect from philosophy and what belongs to a different, less intellectual, mode of explanation. If I say that Descartes' demon is a paranoid fantasy, is that a philosophical explanation or something else - and there's a danger here of straying into something perilously close to personal abuse. One distinction I'm looking at is precisely that difference between something we can attribute to anyone who holds that view and something that may vary from one person to another. I once got myself called a psychopath by someone in a debate about ethics. It was "only philosophy", not a serious rejection of ordinary morality. But my interlocutor seemed unable to make the distinction - or perhaps had just rung out of arguments. The point is, the distinction matters.

I think Witt understands motives as he understands meaning in general, as neither emanating from the subjective nor from the objective side , but as arising out of the interaction. Our interests are enacted in situations, out of which things strike us as funny , sad, boring or interesting in any unlimited variety of ways . When Wittgenstein uses terms like "dissatisfaction," "wants," and "wishes’ with respect to grammatical illusions, the want or wish is an expression of the intellectual disquiet caused by the grammatical picture. The picture's power is what causes the desire, rather than a pre-existing desire creating or contributing to the tendency to create grammatical illusions. — Joshs

Yes. This is very helpful - especially the emphasis on interaction and the picture as itselt a factor in what goes on.