Yes, I have seen it expressed that way. I don't think it does more than make an interesting beginning for a theory. Hamlet's version is somewhat different. I've always wondered where it came from - Shakespeare may have thought it up himself, but it is also likely that he read it somewhere.

It's "in the air," especially in England, the birthplace of nominalism, as a sort of extension of theological volanturism. Consider Shakespeare's younger contemporary Milton's great lines:

...What though the field be lost?
All is not lost—the unconquerable will,
And study of revenge, immortal hate,
And courage never to submit or yield:
And what is else not to be overcome?
That glory never shall his wrath or might
Extort from me. To bow and sue for grace
With suppliant knee, and deify his power...

A mind not to be changed by place or time.
The mind is its own place, and in itself
Can make a Heaven of Hell, a Hell of Heaven.
What matter where, if I be still the same,
And what I should be, all but less than he
Whom thunder hath made greater? Here at least
We shall be free; th’ Almighty hath not built
Here for his envy, will not drive us hence:
Here we may reign secure; and, in my choice,
To reign is worth ambition, though in Hell:
Better to reign in Hell than serve in Heaven.

Theological volanturism obviously starts much earlier, but through nominalism and the politics of the Reformation the idea that God makes whatever is good or bad so by a sort of bare act of will gets transferred over to man. There is, strictly speaking, no Good, but what is called "good " God obviously still has the claim the proper authority, and those who opposed him will suffer no doubt, but it is at least not incoherent for Satan to proclaim "evil be thou my good." Whereas on the realist account that comes through the via antiqua, while evil can obviously still be willed, this always involves a certain sort of ignorance, since evil itself is nothing, a privation of perfection and of being.

This reminds me that I have a PM from @boundless I need to respond to, but we were talking about how this volanturism emerges following the Black Death, but also why it seems to come to Islam first and is more successful there.

Ah, I see. You are using "truly" to distinguish a realist concept from an ant-realist concept. In which case we are just talking about two concepts of desirability, and a concept is either useful or not, and never true or not. Yes. I'm dodging the question. That's because I don't know what I think (yet).

Sort of. When there is an appeal to usefulness to ground practical reason, which appears to become groundless in anti-realism, the next obvious question seems to be "what do we mean by useful?" Are there facts about what is useful, or is it just a matter of taste? Is "the mind is its own place, and in itself can make a Heaven of Hell, a Hell of Heaven," and is "nothing good or bad but thinking makes it so?" This would seem to imply than anything can be useful, according to an act of will.

I think most anti-realists allow that some things can be factually more or less useful towards some end, since this seems to be an obvious empirical fact (e.g. you cannot smash rocks with a hammer made from butter). But in denying any 'higher ends' by which proximate ends are ordered they seem to rule out any sort of ordering for "usefulness," which seems to lead towards the idea that "useful" is just whatever we just so happen to consider to be useful at the moment.

But this has problems to. Regret is a ubiquitous experience. Are we to say that those last tequila shots of the night were "useful" when I was feeling no pain and gulping then down, but the self-same event became unuseful when I awoke brutally hung over hours later? The phenomena of regret might suggest that what is "useful" is what we will consider useful at some point in the future, or with more information, but here the issue is that there seems to be facts about this sort of usefulness, and the idea that more information helps ground practical judgement is at odds with the idea that they are afactual.

Well, it often means that, though, I would say, never just means that. See above.

Indeed, because this position has clear difficulties if not moderated. And yet an expansive volanturism seems to imply that it must be so, else the will is constrained in what is considered good or bad, which would seem to suggest the possibility that "what we are" and "what things are" determines their "usefulness," which again, seems very fact-like and less "taste-like." I think the difficulty here is avoiding inconsistency. So, when Rorty debates Eco, he wants to say that what a screwdriver is doesn't necessitate (or even "suggest") how we use it, since we could just as well use it to scratch our ear as turn a screw, and yet in an obvious sense this isn't so. A razor sharp hunting knife is not a good toy to throw into a baby's crib (at the very least, for the baby) because of what both are, and this is true across all cultural boundaries and seems that it must be true.

It all depends on what you mean by rationality. Conventional logic, as I'm sure you know, can't establish good and bad. But we can reason about good and bad, ends and means. Why would anyone want to deny that we desire truth (on the whole) and goodness (so far as we understand it)?

It's the denial of the appetite for them as such. So it doesn't deny that we might desire truth to attain some other means, but it does deny a rational appetite to know truth of itself that is a part of reason. IDK, this seems to be all over modern anthropology. Homo oecononimicus maximizes utility, and desire for truth is rolled into that black box and generally ignored. Rawls' bare abstract agent is invested in procedural reason, not the old intellectual appetites. Hume says quite straightforwardly that reason can never motivate action, full stop. Reason becomes entierly instrumental. Likewise, "the merit of benevolence, arising from its utility, is a proof that the notions of morals are not derived from reason."

Nor can Hume just say, "but people just possess a sentiment for goodness itself," because this would obviously imply that there is something, goodness, to have an appetite for, which is distinct from people's other sentiments, which is at odds with the entire thesis.

Now you have me puzzled. Why would anyone deny that we have a concept of morality, and of ethics?

They don't, and I'm not sure how you read that as a denial of the existence of the field of ethics. Rather, the denial is that ethics has any real subject matter outside opinion and illusory judgement. It is just taste and emotional sentiment. Plenty of users here make this sort of claim, and plenty of famous thinkers.

Yes. Sometimes, however, they do so because they think that position A does not imply position B. So I need details.

This:

Where am I, or what? From what causes do I derive my existence, and to what condition shall I return? ... I am confounded with all these questions, and begin to fancy myself in the most deplorable condition imaginable, environed with the deepest darkness, and utterly deprived of the use of every member and faculty.

Most fortunately it happens, that since Reason is incapable of dispelling these clouds, Nature herself suffices to that purpose, and cures me of this philosophical melancholy and delirium, either by relaxing this bent of mind, or by some avocation, and lively impression of my senses, which obliterate all these chimeras. I dine, I play a game of backgammon, I converse, and am merry with my friends. And when, after three or four hours' amusement, I would return to these speculations, they appear so cold, and strained, and ridiculous, that I cannot find in my heart to enter into them any farther.

...is not a philosophical resolution of skepticism. The anguished skeptic can just say: "well it still bothers me."

Fascinating. Could you let me have the reference so I can look it up?

There are lots of critiques of Hume's attempt to ground morality in a sort of universal sentiment and average utility. MacIntyre's treatment in After Virtue comes to mind. A key point is that it doesn't keep egoism out, see the point above. It does not imply that it is actually better for us not to act like egoists and lie and cheat, etc. just in cases where we know we can get away with it. To the claim: "but people have a tendency to not want to do that sort of thing," the egoist can just reply "but I do want to do it."

Arguably, Hume might not contradict himself, if we take his "grounding in sentiment" to be purely descriptive. But then he hasn't done anything to ground morality either, and hasn't justified a move from moral nihilism the way he claims he has. So it's a sort of damned if you do, damned if you don't.

Good discussion.

Again, we'd need to really dig in to his reasons for "inventing" Methodical Doubt, and what he hoped it could accomplish. I'm willing, if you like.
— J
OK. Hit me. — Ludwig V

It occurs to me that maybe the best way to do this is for you to say why Methodical Doubt is a "wrong idea." That way I could try to articulate what I understand as Descartes' reasons so as to address your points specifically, rather than just paraphrase the Discourse and Meditations.

It's that insistence on being absolutely certain now that creates much of the problem. — Ludwig V

Interesting. I don't know that Descartes addresses this question. His "Pure Enquirer" is definitely imagined as a 1st person, present-tense viewpoint.

But Descartes' project is removed from any specific context, and it's target is everything he, and we, think we know. — Ludwig V

We'll get into this, I'm sure, but I believe the project does have a specific context -- that of attempting through 1st person reflection to arrive at a standard of certainty out of which we can build up our knowledge. What you mean, I guess, is that there is no specific context of ordinary doubt, the sort we come upon in daily life. But I'm arguing that it's precisely the genius of the method that this be the case. Can you keep open the possibility that he is simply not "doubting things" in the ordinary way, and that there's method to his madness?

People forget that something can be possible and not the case. — Ludwig V

Not Descartes! He insists on this. As discussed above, he is interested in what is possible, not actual.

it is, in theory, possible that I do not have two hands. But if I consider the idea carefully, it makes no sense; there is not the remotest actual argument for supposing that I do not have two hands. — Ludwig V

Well, you know what Descartes would say to that: The evil demon has done a very good job here. He has convinced you that your senses are completely reliable, and the resulting beliefs incorrigible. Or to leave the demon out of it: Dreams can be very realistic. We rarely doubt what they represent to us. It is possible, then, that I am something quite other than what I appear to myself to be, and only imagining the reality I experience.

Let me stress again, Descartes doesn't believe this. It's the "pre-emptive skepticism" idea again. He's saying, "Let no one ever accuse me of not taking every conceivable skeptical possibility seriously." If you don't think that doubting your hands is a skeptical possibility, no matter. This counts nothing against the method; you're just saying that Descartes is over-scrupulous or too imaginative.

one of the founders of philosophy discovered that he knew nothing and the other unwittingly showed that it is not possible to know anything anyway. No wonder philosophy is a mess. — Ludwig V

That's clever, but I hope you acknowledge that both those characterizations of the founders are highly debatable. If Descartes really "showed that it is not possible to know anything," why has that conclusion not won universal acceptance?

Are there facts about what is useful, or is it just a matter of taste? — Count Timothy von Icarus

I would say that there are facts about what is useful, but that they are contextual, not absolute.

Is "the mind is its own place, and in itself can make a Heaven of Hell, a Hell of Heaven," and is "nothing good or bad but thinking makes it so?" — Count Timothy von Icarus

My answers are "yes" and "needs clarification".

.....more information helps ground practical judgement is at odds with the idea that they are afactual. — Count Timothy von Icarus

That's true. But there is no problem about that. Practical judgement is a combination of values, desires and facts. That's what makes it practical. Values and desires are not facts, because they are neither true nor false.

So, when Rorty debates Eco, he wants to say that what a screwdriver is doesn't necessitate (or even "suggest") how we use it, since we could just as well use it to scratch our ear as turn a screw, and yet in an obvious sense this isn't so. — Count Timothy von Icarus

I don't see a problem. A screwdriver has a standard use, which is what is designed for; but it can be used in many different, non-standard, ways. We could call this improvisation, but Derrida has a splendid term for it - bricolage.

A razor sharp hunting knife is not a good toy to throw into a baby's crib (at the very least, for the baby) because of what both are, and this is true across all cultural boundaries and seems that it must be true. — Count Timothy von Icarus

Yes. But I'm not sure how you interpret that in the terms of the philosophical arguments.

Hume says quite straightforwardly that reason can never motivate action, full stop. — Count Timothy von Icarus

He does indeed. "Reason is, and ought to be, the slave of the passions." One assumes that he is not deducing the "ought" from the "is". But Aristotle said it first, in the Nicomachaean Ethics, I think Bk. VI. Actually, he said "Reason by itself moves nothing." Not quite the same, but close enough to suspect an ancestral relationship with Hume's remark. (Aristotle goes on to construct the practical syllogism to explain the rational basis for action. Nobody has improved on it, but then nobody has explained how it moves us.)

So it doesn't deny that we might desire truth to attain some other means, but it does deny a rational appetite to know truth of itself that is a part of reason. IDK, this seems to be all over modern anthropology. — Count Timothy von Icarus

H'm. I take this as about the distinction between wanting something for the sake of something else "external" to it and wanting that thing for it's own sake. The difference between playing music to entertain people in order to earn money and playing music for it's own sake - no ulterior motive; ("For pleasure would not count as an ulterior (or external) motive).
It's curious that you call the latter ("for its own sake") a rational appetite, when the point is that it has no external ground or purpose, whereas playing music for money does, and therefore has a reason, so is clearly rational. Can you help me?

Nor can Hume just say, "but people just possess a sentiment for goodness itself," because this would obviously imply that there is something, goodness, to have an appetite for, which is distinct from people's other sentiments, which is at odds with the entire thesis. — Count Timothy von Icarus

I don't think that's a problem. What "useful" means depends entirely on the context - it isn't a property in its own right, capable of applying to something independently of other properties; it applies to something in virtue of some other properties or qualities that the something has or doesn't have. Similarly, what's good depends entirely on the context.

They don't, and I'm not sure how you read that as a denial of the existence of the field of ethics. Rather, the denial is that ethics has any real subject matter outside opinion and illusory judgement. It is just taste and emotional sentiment. — Count Timothy von Icarus

Oh, I see. I'm sorry that I misread you. Though, I'm sure you will agree that they would not necessarily describe what they are denying in that way.

"And when, after three or four hours' amusement, I would return to these speculations, they appear so cold, and strained, and ridiculous, that I cannot find in my heart to enter into them any farther." is not a philosophical resolution of skepticism. The anguished skeptic can just say: "well it still bothers me." — Count Timothy von Icarus

No, it is not. But then, Hume's point is that there is no philosophical resolution of scepticism. The reason he is not bothered by that is that he thinks it has no point, no consequences. Life goes on, just as usual. Essentially, that's his point about induction. There is no justification that reason can supply, so we will continue to rely on it, just as we have always done. It's not as if there is a useful alternative. He's not wrong, IMO.

Arguably, Hume might not contradict himself, if we take his "grounding in sentiment" to be purely descriptive. But then he hasn't done anything to ground morality either, and hasn't justified a move from moral nihilism the way he claims he has. So it's a sort of damned if you do, damned if you don't. — Count Timothy von Icarus

I don't remember the texts (not Hume, and not Macintyre, either.) enough to engage with this properly. You are right that if his theory is purely descriptive, then it cannot justify ("ground") morality. Perhaps Hume thinks that the fact that we do value the things that we value is all the ground we need? Or perhaps he is thinking of the issue in the same way as he thinks of the philosophical sceptic. The arguments may be impeccable, but they won't make any difference - we shall continue to value the things that we value. However, while we can comfortably let philosophical sceptics moulder in their prison, it is harder to ignore the moral nihilist who ignores the moral rules.
I did, a little while ago, look at his argument about miracles. There, he uses as his final court of appeal "universal agreement" about various things. That does seem a bit of a broken reed, particular when "universal" means "people like me". That is a real weakness. But philosophers do tend to refer to a "we" that believes or does, this and that. I've never been happy with that, but it is almost impossible not to rely on it without awkward and long-winded circumlocutions.

Can you keep open the possibility that he is simply not "doubting things" in the ordinary way, and that there's method to his madness? — J

I can see that he has thought about what he is doing, and is not just doing it for entertainment or on some other impulse. But I can't pretend, to myself or you, that I think there is a sound basis for the project in what he says.
Reviewing one's assumptions is not a bad idea. Copernicus reviewed the assumption that the earth was the centre of the universe. Kepler reviewed the assumption that the planets moved in circles. Newton reviewed the assumption that different physical laws applied to the stars and the earth. In addition Euclid's geometry was a great success. It started from a few definitions and axioms and drew a whole world from it. Descartes is following success and taking it further. But that's where the problems arise. So, to question axioms with theoretical doubts in a theoretical context is a good thing (provided it is not over-done!). But Descartes doesn't set up a theoretical context that gives sense and meaning (and so the possibility of resolving things) to his doubts.
However, there's no problem about agreeing to disagree and moving on to other things. That's a perfectly normal thing to do in conversations like this. Is that what you had in mind?

Not Descartes! He insists on this. As discussed above, he is interested in what is possible, not actual. — J

I get that. But I don't think it defuses very much of what I've been banging on about. If he is prepared to believe in the possibility of the evil demon, his concept of possibility is much more elastic than mine. In the context of a pscychiatric assessment, that could count as evidence of losing touch with reality. But he has invoked "methodical", so I suppose he gets a pass.

It is possible, then, that I am something quite other than what I appear to myself to be, and only imagining the reality I experience. — J

There is a difficult argument here about how "other" you can be and still be yourself. You might have been born in a very different environment and grown up as a very different person - so different that you would not have been the person that you are. Where's that line? Hard to say, but it exists.
Again, if you opened up that discussion in a psychiatric consultation, you would have some explaining to do. But again "methodical" gets you a pass.

It's the "pre-emptive skepticism" idea again. — J

I can understand that. We can assess it, then, by considering how far he set these doubts to rest. Sadly, that was not very far. We might point out that it did provoke a good deal of serious philosophical thought about how to meet the challenge. Which is a success of a sort.

you're just saying that Descartes is over-scrupulous or too imaginative. — J

Perhaps. It is possible to be so scrupulous that you prevent yourself from achieving what you want to achieve. It is also possible to be so imaginative that you lose touch with reality.

It occurs to me that maybe the best way to do this is for you to say why Methodical Doubt is a "wrong idea." That way I could try to articulate what I understand as Descartes' reasons so as to address your points specifically, rather than just paraphrase the Discourse and Meditations. — J

If a quotation from the texts answers my objection, there's nothing wrong with quoting it.
But here is my attempt to rationalize the arguments I've put into a single, possibly coherent statement. But I haven't tried to re-state them. I'm assuming you can remember what they were. There's not an awful lot of text, so you should be able to find the relevant parts of my messages if your memory lets you down:-

What does “methodical” doubt mean (other than as a get-out-of-jail-free card)?
Questioning one’s data, axioms, assumptions in a theoretical context is fine. The context limits the corrosion and ensures that there are ways to distinguish true from false. But without context, one just gets universal corrosion.

Can one choose to doubt (or believe)?
One cannot doubt or believe to order. What gives rise to doubt or belief is evidence. Doubt and belief that is not based on, or at least open to the effects of, evidence is irrational.

The demon
This isn’t really an argument, but more of a way of making it easier to apply radical doubt more widely. In any normal situation it would be a paranoid fantasy, but so it’s as well that it doesn’t really affect the argument.

What can he not doubt at all?
He mentions that he is certain of his own sanity. His expresses concerns about his own memory but believes he has a way of relying on it.
He doesn’t mention reason (law of excluded middle and non-contradiction), his knowledge of language or his pen and paper or the existence of his future readers. Doubting any of these would wreck the project.

The Argument from Experience
He says he has been deceived by his senses, so he will mistrust all sense-experience. He also says he has been deceived in a dream, so he does not know he is not dreaming now.
Doubting some sense-experience makes sense, but not the whole class. It is more accurate to say that our experience (senses or dreams) does not prove that everything is doubtful, but that we can tell true from false.
Wittgenstein’s concept of hinge propositions and Moore's common sense fits here. Hinge propositions are (mostly empirical) propositions that are so deeply embedded in the network of our understanding that they cannot be coherently doubted without demolishing the possibility of ever knowing anything.

Doubt and Possibility.
There seems to be an assumption that if a proposition is contingent, it is possible that it is false, which means that it cannot becertain and can be doubted. This leaves Descartes with an impossibly strict criterion for indubitablity.
But the argument is invalid. It doesn’t follow from the fact that p is possible that p is true. Logical possibility does not amount to doubt or even uncertainty.

That's clever, but I hope you acknowledge that both those characterizations of the founders are highly debatable. If Descartes really "showed that it is not possible to know anything," why has that conclusion not won universal acceptance? — J

It is a serious distortion of what Descartes actually said. I was thinking more of his effect on generations of philosophers after him. Perhaps the failure of his constructive phase is, in a way, not his fault. But it was a serious failure, at least for philosophy. Ordinary life, of course, has muddled on as usual. But that's part of my complaint.
My parents had a phrase "that's clever-clever" which they frequently applied to me in my teens. It meant something like "clever and annoying" or "clever on the surface but pointless when you think about it". It applies to this paragraph. I should have deleted it rather than posting it.

there's no problem about agreeing to disagree and moving on to other things. That's a perfectly normal thing to do in conversations like this. Is that what you had in mind? — Ludwig V

I'd thought we could focus more on why Descartes chose methodical doubt as a way to establish certainty. But given the many objections you raise, and given your honesty that you're not really open to the idea that there could be a sound basis for it, I'm fine with letting it go. Agreeing to disagree about Descartes' project is almost a sure sign of philosophical maturity! :smile:

We can assess it, then, by considering how far he set these doubts to rest. Sadly, that was not very far. — Ludwig V

This is another, separate question, also interesting. I assume you don't think Descartes was successful in raising his methodical doubt, given your objections to the method. But are you saying that he failed to set the doubts to rest on his own terms? -- that is, allowing for the purpose of argument that real doubts were raised, are you saying he failed to allay them in the ways he believed he had?

Questioning one’s data, axioms, assumptions in a theoretical context is fine. The context limits the corrosion and ensures that there are ways to distinguish true from false. But without context, one just gets universal corrosion. — Ludwig V

This is the only one of your objections I'd really want to push back on. I'm having trouble seeing why Descartes doesn't have a legitimate theoretical context. Maybe you can give an example of a theoretical context where "questioning one's data . . ." etc. does make sense?

"clever on the surface but pointless when you think about it". It applies to this paragraph. I should have deleted it rather than posting it. — Ludwig V

Oh no worries. Just checking to make sure you didn't really believe it was that simple! :wink:

Agreeing to disagree about Descartes' project is almost a sure sign of philosophical maturity! :smile: — J

I hope, at my age, I can at least claim to something like philosophical maturity!

I'd thought we could focus more on why Descartes chose methodical doubt as a way to establish certainty. But given the many objections you raise, and given your honesty that you're not really open to the idea that there could be a sound basis for it, I'm fine with letting it go. — J

I'm not saying I couldn't be convinced. The core of the problem is that, so far as I can see, Descartes has little or nothing to tell us about what he means by "methodical doubt", so it looks as if he thought it was obvious. His astonishment that people took the idea of doubting everything more seriously than he intended shows, I would say, that he hadn't thought it through very much.

This is the only one of your objections I'd really want to push back on. I'm having trouble seeing why Descartes doesn't have a legitimate theoretical context. Maybe you can give an example of a theoretical context where "questioning one's data . . ." etc. does make sense? — J

That's fair enough. I have elaborated, or even qualified, my objection in my previous message. Here it is again:-

Reviewing one's assumptions is not a bad idea. Copernicus reviewed the assumption that the earth was the centre of the universe. Kepler reviewed the assumption that the planets moved in circles. Newton reviewed the assumption that different physical laws applied to the stars and the earth. In addition Euclid's geometry was a great success. It started from a few definitions and axioms and drew a whole world from it. Descartes is following success and taking it further. But that's where the problems arise. So, to question axioms with theoretical doubts in a theoretical context is a good thing (provided it is not over-done!). But Descartes doesn't set up a theoretical context that gives sense and meaning (and so the possibility of resolving things) to his doubts. — Ludwig V

If you consider these cases, you can see that the theoretical context includes ways of questioning axioms, replacing them with others and methods of working through the consequences and proving the results. (Essentially, mathematical workings to draw out the implications of the data and prove that the new model made better predications that the orthodox ideas.) You could argue that in following the mathematical format, that is what he is trying to do. But the format does not work in the context of this project. One obvious problem is that the data is not systematically organized or in a format that allows mathematical methods to be applied. The other is that the assumption that all knowledge can be turned into a single comprehensive logical structure is, to put it politely, a massive task with no guarantee of success. (Bear in mind, here, that the new science (with Descartes' help) decided to exclude anything that could not be handled mathematically, such as colours and sounds, not to mention emotions and values. But those are part of what he is now taking on.)
Perhaps looking at his constructive phase - the cogito and what follows will make this clearer.

This is another, separate question, also interesting. I assume you don't think Descartes was successful in raising his methodical doubt, given your objections to the method. But are you saying that he failed to set the doubts to rest on his own terms? -- that is, allowing for the purpose of argument that real doubts were raised, are you saying he failed to allay them in the ways he believed he had? — J

That's not just my opinion, There is a raft of issues about the cogito. I think we may be about to move on. I'll need to remind myself about all that, so it may take a little while.

Oh no worries. Just checking to make sure you didn't really believe it was that simple! :wink: — J

I'm glad of that. This medium is not kind to subtleties that can easily be conveyed in actual conversation. There was no way that I could inflect my voice or face to say - don't take this too seriously. I'm not adept with smileys.

Apologies, I somehow missed both of your replies.

Hmm. Is the cogito meant to be an example of metaphysical certainty? Many philosophers do disagree that the cogito does what Descartes wanted it to, but to say it's been "amply demonstrated" is an exaggeration, wouldn't you say? Or perhaps you have some other level of metaphysical certainty in mind. — J

I'm not sure what you are referring to. Perhaps I didn't articulate my thoughts well there―I meant to say that it has been amply demonstrated that metaphysical certainty in the traditional "absolutist" sense is impossible to attain. Would you not agree that Descartes was attempting to discover what he (and by extension, we) could be certain of vis à vis what necessarily exists?

I think you know from past discussions that I would be the last to indulge in human exceptionalism and conclude that we are somehow more than mere animals. We are only exceptional inasmuch as we are very unusual animals. That said, there are also many other very unusual animals.
— Janus
Sorry. That remark was intended in general, not in particular. I write quite quickly when I finally get to the keyboard. Sometimes I don't put things precisely enough. But I've found that if I write too slowly, I end up not writing at all. — Ludwig V

just in case there has been a misunderstanding I was not thinking you were accusing me of human exceptionalism, so no apology needed.

It seems to me to be a question of what we can logically doubt, and I think the answer is 'anything that can be imagined to be false without logical contradiction'. It seems we cannot doubt the LNC itself without falling into incoherence.
— Janus
There's a good point there. If Descartes does try to doubt the LNC, the project will fall apart. Same thing if he doubts his memory. He makes quite a fuss about that at the end of the first meditation.

As I think Ludwig is suggesting my point was that any discourse which purported to deny the LNC must necessarily be involved in an incoherent performative contradiction because to do so would undermine discourse itself.

The obverse is what we can absolutely certain of; and I think that would be only what is true by definition or according to some rule or set of rules we have accepted; i.e. tautologies and mathematics and they really tell us nothing outside of their contexts.
— Janus
Yes. That's a trap. The price of absolutely certainty is paralysis in the empirical world. But perhaps we don't live in the empirical world? If we want to return to normal life (a dubious prospect, but still..) we need to re-cast this conceptual space. That's what Wittgenstein is trying to do - and, in his way, Moore.

I don't see people as living wholly within the empirical world. As Sellars pointed out we live with both the scientific images and the manifest images of the world, or within the space of causes and the space of reasons. The latter cannot be understood (parsimoniously at least) solely in terms of causes.

Indeed, he says that the evil demon could make us wrong even about "2+2 = 4". Would he agree, then, that his methodical doubt should exempt logical truths? Evidently not. "I think," for Descartes, has a certainty and an incorrigibility that "LNC" does not. — J

I have only just discovered this message of yours. It certainly changes things a lot. It shows how easy it is to get things wrong if you don't read the text again from time to time.
I think we need to remember that in Descartes's time, the idea that logic was the foundation of mathematics was far in the future. He would have seen the LNC and the cogito as a different category from mathematical truths. I really don't know what the ideas were at the time.

As I think Ludwig is suggesting my point was that any discourse which purported to deny the LNC must necessarily be involved in an incoherent performative contradiction because to do so would undermine discourse itself. — Janus

If we see the LNC and the Law of Excluded Middle as both undermining the possibility of making an assertion, then the cogito will fit beside them, because it is validated in the act of asserting it. I don't recall any commentary that takes on board his inclusion of mathematical truths in his methodical doubt.
Perhaps @J could check Williams' book and see what he says?

I don't see people as living wholly within the empirical world. As Sellars pointed out we live with both the scientific images and the manifest images of the world, or within the space of causes and the space of reasons. The latter cannot be understood (parsimoniously at least) solely in terms of causes. — Janus

I wouldn't say that people live wholly in the empirical world. That thought was badly expressed. I wouldn't disagree with Sellars.

There is a raft of issues about the cogito. — Ludwig V

Oh, indeed. Descartes himself dealt with a number of objections from people who pointed out that the "I" in "I think" could use a lot more specification. And there is the so-called "impersonal cogito," which considers whether it should more properly be phrased as "there is thinking going on" rather than "I think". (Williams analyzes this one at some length and believes it is an incoherent objection.)

I meant to say that it has been amply demonstrated that metaphysical certainty in the traditional "absolutist" sense is impossible to attain. Would you not agree that Descartes was attempting to discover what he (and by extension, we) could be certain of vis à vis what necessarily exists? — Janus

Yes, I would (and of course we understand that "necessarily exists" doesn't mean "must exist". It means, given the fact of thinking, then necessarily I must exist.) And given the continuing lively debate about Descartes' project, and much else in metaphysics, I say again that "amply demonstrated" and "impossible" are too strong. I'm agnostic, leaning toward skeptic, about metaphysical certainty, but the debate is hardly over.

As I think Ludwig is suggesting my point was that any discourse which purported to deny the LNC must necessarily be involved in an incoherent performative contradiction because to do so would undermine discourse itself. — Janus

Yes, with a few qualifications about the type of discourse. I appreciate the reminder from Ludwig that logical truths and their role in reasoning was a different animal, back in Descartes' time. It is part of Descartes' interesting "flavor" that his approach is so subjective, so first-personal, attempting to find certainty in experience rather than what we would call analyticity.

the space of causes and the space of reasons. The latter cannot be understood (parsimoniously at least) solely in terms of causes. — Janus

I agree. In the current context, though, Ludwig probably meant "empirical" to cover both. Oh yes, I now see he agrees with Sellars. But the problem being raised is whether:

The price of absolutely certainty is paralysis in the empirical world.

which would remain a problem however you choose to construe "empirical." My view is that there's no reason to restrict one's actions to what can be based on certainty. It's a good question whether Descartes would have viewed lack of certainty as a reason for inaction. Maybe it's somewhere in his writings.

Perhaps J could check Williams' book and see what he says? (about mathematical truths) — Ludwig V

I will. The book is so good that I'm reading it slowly, lots of notes, and have only gotten to God! Williams is quite hard on D here, as are most philosophers I've read.

attempting to find certainty in experience rather than what we would call analyticity. — J

Yes. Though I don't think he would have thought of it that way. Most likely, he would have thought of reason as the primary source of knowledge.

My view is that there's no reason to restrict one's actions to what can be based on certainty. — J

There's a bit of an ongoing issue about that. I prefer to insist on certainty, but alter the definition to something we can achieve - i.e. not simply the logical possibility of being wrong. People like you prefer to insist that it is not irrational to act on high probabilities. It's pretty much six of one and half a dozen of the other.

The book is so good that I'm reading it slowly, lots of notes, and have only gotten to God! Williams is quite hard on D here, as are most philosophers I've read. — J

It's wonderful to find a philosophy book that one just wants to read it slowly. Most philosophers are hard on someone who believes in God. Some people, though, suspect that he was just paying lip service.

Descartes himself dealt with a number of objections from people who pointed out that the "I" in "I think" could use a lot more specification. And there is the so-called "impersonal cogito," which considers whether it should more properly be phrased as "there is thinking going on" rather than "I think". (Williams analyzes this one at some length and believes it is an incoherent objection.) — J

I think the point is that D will be aware of his thought, but not of himself thinking it. The observing self is never part of what is observed, so it's existence is a deduction. So even on the impersonal view, D's own existence will be proved as the first next step. D's view of it is "he does not deduce existence from thought by means of a syllogism, but recognizes it as something self-evident by a simple intuition of the mind". The concepts of self-evidence and intuition are not popular in modern philosophy, mainly because they are unreliable guides to truth. (I'm sure you see the irony!).

Not that I think he is wrong. His argument is "If I convinced myself of something [or thought anything at all], then I certainly existed. But there is a deceiver of supreme power and cunning who deliberately and constantly deceives me. In that case, I, too, undoubtedly exist, if he deceives me; and let him deceive me as much as he can, he will never bring it about that I am nothing, so long as I think that I am something." So, the doubter can doubt everything, but the act of doubting reveals his own existence. To put it in modern terms, asserting "I am thinking" itself proves that he exists. It is a self-confirming assertion. Compare, for example "I am here". Stanford Encyclopedia - Descartes' Epistemology (See section 4.1) attributes this view to Hintikka and discusses it more detail

However, the idea that the cogito is an inference still has supporters, who argue that D's rejection of proof by syllogism does not exclude an inference. I think this is not a strong answer - a bit like a lawyer wriggling. However, you can find a detailed discussion in the SEP article above.

I think the two most discussed views nowadays are these two - inference and performance. There are others, including Williams' own critique. Wikipedia - cogito ergo sum has objections from Kierkegaard, Heidegger, Macmurray, and Whitehead. I hope you don't mind if I refer you to Wikipedia for those.

It is possible to get lost for quite a while in this. But, however it is interpreted, what matters most is what he does with it. So I suggest you at least look at the rest of Meditation II and consider whether his process does what he needs it to do. I'll be interested to know what Williams says about this.

PS - a last point.

I appreciate the reminder from Ludwig that logical truths and their role in reasoning was a different animal, back in Descartes' time. — J

I found it hard to find the answer to the question what philosophy of mathematics Descartes might have espoused. So far as I can see, the existing orthodox philosophy centred on the idea of mathematical objects - all variants of platonism, in a way. But mathematics was in the throes of a major upheaval at the time - to which Descartes contributed. So anything is possible. But I don't see how he could align mathematics and logic without modern logic.

So, the doubter can doubt everything, but the act of doubting reveals his own existence. — Ludwig V

Just a quick response for now: Yes, this is what Descartes says too, and Williams tells us that both "je pense" and "cogito" were much broader than the English "I think". Descartes would have meant something closer to "I have mental experiences" or "I am conscious". The cogito does not imply a consciously formed thought, as we might say in English, "I thought of that" or "I had that thought." And this becomes important in understanding exactly what Descartes believes we can infer from the cogito: You don't have to form the thought "I think" in order to be thinking, on his usage. Self-awareness is not part of existence.

You don't have to form the thought "I think" in order to be thinking, on his usage. — J

I've not heard that before, that I remember. It cuts out a lot of messing about, so it is a very interesting idea.
So we can paraphrase it as "Whenever I think something, I exist", or "If I think, I exist" which certainly makes it not performative and supports the inference (provided we hold D. to a narrow interpretation of syllogism. It also cuts out Gassendi's argument about "I" and makes sense of the way that he derives the illumination by reflecting on what the demon has been doing to him, rather than what the demon is doing now. Does he need to trust his memory?

However, it is a subtle aspect of the meaning. I checked the classical Latin cogito and the entry did not clarify the point one way or the other. I don't know enough to argue about the finer points of 17th century French or Latin usage in 17th century France. Does he back his claim up?

If we see the LNC and the Law of Excluded Middle as both undermining the possibility of making an assertion, then the cogito will fit beside them, because it is validated in the act of asserting it. — Ludwig V

I think you meant to say the rejection of the LNC and the LEM? In a purely semantic or logical sense saying "I think" or "I do X" ( where "X" could be anything at all) means or entails that "I" exists, to be sure.

And there is the so-called "impersonal cogito," which considers whether it should more properly be phrased as "there is thinking going on" rather than "I think". (Williams analyzes this one at some length and believes it is an incoherent objection.) — J

The question, beyond the purely semantic or logical entailment of "I" in "I think" is as to in what sense the I exists, or in other words, just what is the I. Changing it to "there is thinking going on" seems reasonable, although it begs the question as to what thinking is, beyond the logical entailment that any assertion is an example of thought.

I am not well-read in Descartes, but I have the impression that he is looking for substantive or metaphysical proofs of existence, not merely stipulative semantic ones.

I say again that "amply demonstrated" and "impossible" are too strong. I'm agnostic, leaning toward skeptic, about metaphysical certainty, but the debate is hardly over. — J

Perhaps I am more skeptical than you in thinking that it is not possible that the debate could ever be over. I mean the situation seems quite different than in the sciences where new information can always come to light―in the context of purely rational thought, wherein it seems to be writ that empirical findings have no demonstrable metaphysical implications, where is any new information going to come from?

I don't know enough to argue about the finer points of 17th century French or Latin usage in 17th century France. Does he back his claim up? — Ludwig V

He quotes this, from the Principles:

"All forms of consciousness (modi cogitandi) that we experience can be brought down to two general kinds: one is cognition (perceptio), or the operation of the intellect; the other is volition, the operation of the will. Sensation, imagination, and pure intellection are just various forms of cognition; desire, aversion, assertion, denial, doubt, are various forms of volition."

and concludes that

For Descartes, a cogitatio or a pensee is any sort of conscious state or activity whatsoever; it can as well be a sensation (at least in its purely psychological aspect) or an act of will, as a judgment or a belief or intellectual questioning. — Williams, 78

To give the most charitable hearing to Descartes' project, I think we ought to agree that this is what he meant. Consider a memory -- say, of the Brooklyn Bridge. When it comes to mind, do we say that I have "thought" the Brooklyn Bridge? Not really; in English, that's awkward. But such an example would surely serve for Descartes' point -- if I can have such an experience, I must exist. Whether we call it an English "thought" or a French "pensee" or simply a mental event doesn't really affect the point.

I say again that "amply demonstrated" and "impossible" are too strong. I'm agnostic, leaning toward skeptic, about metaphysical certainty, but the debate is hardly over. — J

I'm afraid that I have never understood exactly what metaphysical certainty is, so I'm not going to express an opinion.

Perhaps I am more skeptical than you in thinking that it is not possible that the debate could ever be over. I mean the situation seems quite different than in the sciences where new information can always come to light―in the context of purely rational thought, wherein it seems to be writ that empirical findings have no demonstrable metaphysical implications, where is any new information going to come from? — Janus

I agree that it's not a question of new information. But that doesn't mean that new ways of thinking about the problem, especially new ways of interpreting what we already know, are ever entirely impossible. I tend to see what are labelled metaphysical questions as questions of interpretation. So the developments that started the analytic tradition bring a new perspective to old questions and enable debates to radically change. Questions of interpretation don't have closure in the way that questions of information or even rationality sometimes do.

To give the most charitable hearing to Descartes' project, I think we ought to agree that this is what he meant. Consider a memory -- say, of the Brooklyn Bridge. When it comes to mind, do we say that I have "thought" the Brooklyn Bridge? Not really; in English, that's awkward. But such an example would surely serve for Descartes' point -- if I can have such an experience, I must exist. Whether we call it an English "thought" or a French "pensee" or simply a mental event doesn't really affect the point. — J

The quotation from the Principles does confirm Williams' reading. That reading is also at least compatible with the Meditations. I'm convinced. I've never been keen on the dancing around with Descartes' self. It all seems a bit gossamer, even subjective.

As others have pointed out in this discussion, you begin from a concept of the real as something that is presumed to have an absolute status in itself, such that our failures at grasping or modeling or holding onto it constitute illusions, falsehoods, mirages. One wouldn’t speak this way about a the real unless we believed it were the kind of thing that an unquestionable and absolute status. But if we can never directly attain the real through our representations and models, what allows us to think about it at all?

Our concept of the real in terms of what it is we are failing to attain must hold some kernel of the real within itself, no? For instance, what is it that allows the real to slip from our grasp? The enemy of the real would seem to be change, impermanence, transformation, unpredictability. The real
must be that which can reliably be returned to over and over again as the exact same. And where do we find the basis of this capacity in our concepts? We find it in the pure repetition of number. We might be then be inclined to say that mathematics is only possible because there are real things in the world.

But what if we instead say that the pure self-identical repetition that mathematics describes is not modeled after the real world, but invents the very notion of the real as pure self-identity. In that case, when we find ourselves lamenting the failure of human thought to attain the real, we are confusing our own invention (the real as pure, persisting self-identity) with the actual world. This, the reason the real is unattainable is because we can only achieve it by turning away from the actually experienced world in order to create the empty abstractions of mathematics. We have a choice. We can have the real in its purity if we abstract from experience all contextual meaning and relevance and calculate emptily. Or we can experience the world meaningfully in its rich contextually changing unfolding, and use the mathematical concept of the purely , self-identically real as a tool of convenience.

I am not well-read in Descartes, but I have the impression that he is looking for substantive or metaphysical proofs of existence, not merely stipulative semantic ones. — Janus

I agree. So the question is whether the "I" in "I think" can survive the change to "there is thinking going on," not semantically, but in terms of a demonstration of some actual entity called "the self" or "I". As I mentioned, Williams goes into a lot of detail on this and I don't have it all under my belt, but his main point boils down to claiming that "thinking is going on" can't be given content without some indexical, and that it would be perverse not to accept the most likely candidate, namely "I". He acknowledges that this doesn't provide much knowledge about the self -- but so does Descartes. In fact, Williams says:

The question whether there could be a replacement which fell short of 'A thinks' [that is, something impersonal we could use to replace 'cogito'] is not one that I shall pursue further. The point is that some concrete relativization [indexical] is needed, and even if it could fall short of requiring a subject who has the thoughts, it has to exist in the form of something outside pure thought itself. — Williams, 100

So that's possibly equivocal. I read him as mainly wanting to defeat the idea of an "impersonal formulation," not necessarily concluding that the Cartesian "I" is our only alternative.

Questions of interpretation don't have closure in the way that questions of information or even rationality sometimes do. — Ludwig V

Something like this would be part of my reply to @Janus as well. But as both of you have noted, we can construe "metaphysics" in a number of ways, any one of which will be more or less conducive to the "closure" question. So perhaps not a fruitful line of inquiry.

I agree that it's not a question of new information. But that doesn't mean that new ways of thinking about the problem, especially new ways of interpreting what we already know, are ever entirely impossible. I tend to see what are labelled metaphysical questions as questions of interpretation. So the developments that started the analytic tradition bring a new perspective to old questions and enable debates to radically change. Questions of interpretation don't have closure in the way that questions of information or even rationality sometimes do. — Ludwig V

Right, not new information, but new perspectives based on new interpretations. I agree that metaphysical questions are questions of interpretation. Just as with poetry there can be no closure, and that is not a bug, but a feature. It is the impossibility of closure that leads me to say there can be no certainty in relation to metaphysical speculations.

It is the impossibility of closure that leads me to say there can be no certainty in relation to metaphysical speculations. — Janus

Well, yes. In a way. But in case like this, you may find that people will infer that metaphysical speculations are always uncertain. But that's misleading. Better to say that metaphysical speculations are neither certain nor uncertain. But that doesn't mean that it's an open house. Interpretations do have to meet standards before they are acceptable. You can't interpret the duck-rabbit as a picture of a lion. That's why one talks of interpretations as valid or invalid, (or plausible or not, etc.) rather than true or false.

I don't recall any commentary that takes on board his inclusion of mathematical truths in his methodical doubt.
Perhaps J could check Williams' book and see what he says? — Ludwig V

I think I have Williams' answer here.

He says that Descartes used the term "eternal truths" for what we might call the truths of mathematics, logic, or analyticity. Such truths have the characteristic of "irresistibility" -- once understood, they are seen as necessarily true. When Descartes begins his journey back from doubt, he finds that these eternal (analytic) truths are indeed clearly and distinctly seen to be true. So, Williams asks, how did Descartes overlook this fact previously? How was he able to apply methodical doubt to a series of propositions he now finds irresistible? I think this was your question as well.

Williams writes:

The Doubt got as far as it did only by a measure of inattention. Descartes suspended in the Doubt, managed not to believe, a number of propositions which he now acknowledges to be irresistible; so he cannot have been, at the time of doubting them, properly thinking of them. Descartes accepts this [Williams provides several references]. This gives us another sense in which the Doubt is a 'fiction', besides the now familiar point that it is the procedure of a Pure Enquirer: it also has to proceed by not totally attending, in some cases, to what it is doubting. So a proposition can be really irresistible, and yet there be times at which I can doubt it, namely if I do not think clearly enough about it. — Williams, 186-7

Hmm. What to make of this? It sounds like a flaw in the process of methodical doubt, though Williams doesn't go that far. Also, while he provides the references for Descartes' agreement to this construal, he doesn't quote from them. I think I will chase them down and find out what Descartes actually said. Presumably D himself didn't think this was a flaw, and I'd like to know why.

To be continued.

What is real?" is a metaphysical question. It doesn't have a correct answer

Would you say the question ''what is real?" Doesn't have a correct answer because it is a metaphysical question?

As in for all x if x is a metaphysical question then the answer to that question can't be true or false?

If so why?

Would you say the question ''what is real?" Doesn't have a correct answer because it is a metaphysical question?

As in for all x if x is a metaphysical question then the answer to that question can't be true or false? — Jack2848

If so why? — Jack2848

A statement that can’t be verified or falsified, even in theory, does not have a truth value. Metaphysical statements can’t be verified or falsified.

…in a case like this, you may find that people will infer that metaphysical speculations are always uncertain. But that's misleading. Better to say that metaphysical speculations are neither certain nor uncertain. But that doesn't mean that it's an open house. Interpretations do have to meet standards before they are acceptable. You can't interpret the duck-rabbit as a picture of a lion. That's why one talks of interpretations as valid or invalid, (or plausible or not, etc.) rather than true or false. — Ludwig V

These are standards of correctness, no? It is incorrect to interpret the duck-rabbit as a picture of a lion. Why? Because we are applying a pre-existing standard that says the image must be a duck-rabbit and nothing other than a duck-rabbit. This is the role of a metaphysics. It lays down criteria and standards of correctness. But since such standards apply only WITHIN that metaphysical system, it has nothing to say about an alternative metaphysical stance within which it makes sense to say that a duck-rabbit may also be a lion.

Hmm. What to make of this? It sounds like a flaw in the process of methodical doubt, though Williams doesn't go that far. — J

Fascinating. It looks like a flaw to me. Inattention is feeble. But it is possible to make mistakes in calculations and draw incorrect inferences, though philosophers seem curiously reluctant to mention the fact. No doubt any evil demons around will be only too happy to help that tendency along. So Descartes can maintain his usual premiss and sustain his methodical doubt. But then he faces another challenge, to explain how come those truths that he doubted a little while ago are now seen as are irresistible. There's a possible answer. I guess one could argue that seeing something clearly and distinctly requres that one pay attention to it.

But since such standards apply only WITHIN that metaphysical system, it has nothing to say about an alternative metaphysical stance within which it makes sense to say that a duck-rabbit may also be a lion. — Joshs

My remark that the duck-rabbit can't be a lion was not, so far as I'm aware, a metaphysical claim. It's simply true. The idea that it could be a lion really passes my imagination. What do you mean here by a metaphysical system? Kant versus Berkeley, vs Aquinas etc? Can you elaborate?

My remark that the duck-rabbit can't be a lion was not, so far as I'm aware, a metaphysical claim. It's simply true. The idea that it could be a lion really passes my imagination What do you mean here by a metaphysical system? Kant versus Berkeley, vs Aquinas etc? Can you elaborate? — Ludwig V

I’m equating metaphysical system with paradigm , worldview or Wittgensteinian form of life. Is the duck-rabbit’s not being a lion is simply true, is it simply true in the same way as Moore’s declaration that ‘this is a hand’?

Well, yes. In a way. But in case like this, you may find that people will infer that metaphysical speculations are always uncertain. But that's misleading. Better to say that metaphysical speculations are neither certain nor uncertain. But that doesn't mean that it's an open house. Interpretations do have to meet standards before they are acceptable. You can't interpret the duck-rabbit as a picture of a lion. That's why one talks of interpretations as valid or invalid, (or plausible or not, etc.) rather than true or false. — Ludwig V

What you are saying seems to me to boil down to an assertion that metaphysical speculations must be coherent and make intuitive sense in order to be judged valid and plausible. If so, I agree.

So, it seems reasonable to me to think the Presocratic speculations about cosmic constitution made sense to them in terms of what were thought to be the basic elements and the everyday experience of finding things to be made of different materials.

I’m equating metaphysical system with paradigm , worldview or Wittgensteinian form of life. — Joshs

Poor old W - he must be spinning in his grave. I can see that, in some ways, metaphysical systems may play a part in our lives similar to the part he attributes to "forms of life". But insofar as they are theoretical, in the sense that physics is theoretical, they can't be forms of life.

Is the duck-rabbit’s not being a lion is simply true, is it simply true in the same way as Moore’s declaration that ‘this is a hand’? — Joshs

I think the duck-rabbit's not beiing a lion is simply true. I'm not sure what to say about a picture that has, or at least appears to have just one interpretation - like my picture of my mother. We have to say, I think, that the puzzle pictures are a special case. But seeing my mother in the picture must also be an interpretation. I'm really not sure what to say about this.
I'm not sure what to say about the comparison with Moore's hand. However, one of the points about Moore's hand is that we would not know what to say to someone who insisted on doubting that he himself did not have a hand. We would have to work out what he meant. In that way, I think the two statements are comparable.

So, it seems reasonable to me to think the Presocratic speculations about cosmic constitution made sense to them in terms of what were thought to be the basic elements and the everyday experience of finding things to be made of different materials. — Janus

Certainly they made sense to them. But they don't make sense to us. Now, are we going to worry about whether they made sense simpiciter or in a non-relative sense of making sense. I hope not.

It's easy to dismiss their theories. But some of their questions survive to this day, in the form of logical paradoxes. (It's just that we don't draw the same conclusions from them.) They weren't idiots.

Poor old W - he must be spinning in his grave. I can see that, in some ways, metaphysical systems may play a part in our lives similar to the part he attributes to "forms of life". But insofar as they are theoretical, in the sense that physics is theoretical, they can't be forms of life. — Ludwig V

One can generate a theory in physics , such as the Newtonian or the Quantum model. It can then be revealed how one’s theory is guided by certain metaphysical presuppositions. The presuppositions can tie together a family of theories, just as a form of life can do. The metaphysics may be something one has not explicitly constructed as a formal position; it may instead have been ‘inherited’ from one’s community. I’m getting this concept of metaphysics from contemporary Continental authors, who apparently treat the term in a less technical and more encompassing way than the writers you are drawing from.

But then he faces another challenge, to explain how come those truths that he doubted a little while ago are now seen as are irresistible. — Ludwig V

That challenge, he can handle, in the same way he restores certainty to all the items formerly doubted. More troubling is the "appeal to inattention," a curious defense. Does D have to say that he should not have doubted the "eternal truths"? Or that he should not have been inattentive to them? Does this amount to the same thing, if they're irresistible?

Is the duck-rabbit’s not being a lion is simply true, is it simply true in the same way as Moore’s declaration that ‘this is a hand’?
— @Joshs
I think the duck-rabbit's not being a lion is simply true. — Ludwig V

May I rephrase? Neither of you is debating some point of identity. The claim boils down to, "When I look at the duck-rabbit, it is not possible for me to see a lion." That, at any rate, would be the first-personal version. Should we expand it?: "It is not possible for anyone to see a lion." This all seems to depend on what sense of "possibility" you want to invoke. I guess we should ask Joshs, "Do you mean that we should acknowledge that someone, somewhere, could be taught to see a lion in the duck-rabbit?" If that's the idea, I agree; it is not strictly impossible. But I agree with Ludwig that this has little to do with metaphysics, unless the sort of "Continental-style" use of the word that Josh mentions is needed in order to imagine these uncanny lion-seers. That is, perhaps you need a whole different "inheritance from a community," not just an odd fact about what can be seen in the duck-rabbit.

What about "this is a/my hand"? (If we say "my," we arguably up the certainty factor.) There are two possible rephrasings here, I think: "1) It is not possible for me to not see this as my hand" and "2) It is not possible that this is not my hand." I think Ludwig, and maybe Moore, mean the first; my hand, when seen, has the property of self-evidence. Again, though, is it possible to imagine a tribe or culture in which "being a hand" was not an important thing to notice? In such a case, I suppose I could see my hand but not be sure that "this is a hand," because I don't know the concept.

As for the 2nd rephrasing, we enter semantical issues. Could what I believe is "my hand" be something else? Depends on what we want "my hand" to mean. If I include in "my hand" the idea of "flesh and blood part of my body, which is also flesh and blood, and to which I am related in the ways I believe I am," then sure, doubt is possible. Brains in vats, Matrix, et al. But if we simply mean (as Descartes does, when speaking about "thought" or "doubt") "this apparent experience of an object that I am having," then it's hard to see how this could be doubted by some other metaphysic or belief system. (allowing "object" as a neutral noun, for lack of a better one)

So, is there a difference between "not being able to see the lion" and "not being able to not-see my hand"? Does either one equal "simply true"? I'll keep mum.

Neither of you is debating some point of identity. The claim boils down to, "When I look at the duck-rabbit, it is not possible for me to see a lion." That, at any rate, would be the first-personal version. Should we expand it?: "It is not possible for anyone to see a lion." This all seems to depend on what sense of "possibility" you want to invoke. I guess we should ask Joshs, "Do you mean that we should acknowledge that someone, somewhere, could be taught to see a lion in the duck-rabbit?" If that's the idea, I agree; it is not strictly impossible. But I agree with Ludwig that this has little to do with metaphysics, unless the sort of "Continental-style" use of the word that Josh mentions is needed in order to imagine these uncanny lion-seers. That is, perhaps you need a whole different "inheritance from a community," not just an odd fact about what can be seen in the duck-rabbit — J

Don’t discount odd facts, because what makes them odd connects them to the functioning of a metaphysics. Let me explain. In another thread, Banno pointed out that the difference between a language game and a form of life is that the latter ties together a multitude of language on the basis of family resemblances. I would say the difference is a matter of breadth or scope. The form of life, like a metaphysical stance, has a relative stability about such that it functions as a dependable anchor or hinge. Moore’s certainty concerning his hand relies on his faith that he can repeat the same assertion multiple times, over multiple days or weeks or months, and it will still have the same sense.

But it is important to appreciate that it will never be the exact same sense, because the form of life or hinge making Moore’s assertion intelligible in the way that he means it is slowly morphing over time , but much more slowly than the empirical assertions and language games that it authorizes. Let’s say that a form of life or metaphysical system undergirds the duck-rabbit puzzle. Whatever it consists of, it anchors a much wider range of situations than just the one in which one identifies a figure in a drawing. In the very restrictive situation of the drawing , there is already a lot of background normative criteria that people have in common in order to play the duck-rabbit game. They are agreeing that it is a drawing, that their task is to identify what it resembles, that the figure within it can be interpreted in different ways, they see enough detail in the image to recognize a duck or a rabbit.

It belongs to that language game that a failure to correctly identity the figure as either duck or rabbit is a near impossibility. Why? Because it may be assumed that the image’s structure provides rules for its correct recognition as either duck or rabbit. But the lesson Wittgenstein wants to teach us about the duck-rabbit is that ‘seeing-as’ doesn’t ground itself in the consulting of a picture theory, that is, a set of rules to be followed. ‘Seeing as’ can never rely on a pre-existing rule, fact or criterion, which is why ‘odd facts’ belong to the very nature of ‘seeing something as something, For Witt the ‘near impossibility of seeing the image as a lion results of a confusion arising out of our use of language. ‘Seeing as’ shares with forms of life and metaphysical stances its normative impetus (showing up not what something. is but how it is), a certain stability over time of such normative certainty, and that the consulting of criteria, rules and grounds is. or enough to produce the ‘odd fact’ of actually seeing something as something.