I think this explains it pretty well

Here's a sqip: i

If you take any squip, and put an "i" on it's left side, the result is also a squip.

So since i is a squip, so is ii. and since ii is a squip, so is iii.

You get the idea.

Here's a language game about that language game: Is there a largest squip?

Now, where is the problem? — Banno

That's not a language game. That's a scribble game.

What makes a scribble a word?

Good questions and thoughts here. Just to address one thing quickly:

. Do you mean are there any cases where I feel absolutely certain that something I intuit to be true, but which cannot in any way be tested, is really the case? — Janus

No, I think "absolute certainty" as a synonym for "knowledge" is way too high a bar. I have in mind the same criteria for knowledge we'd use in the ordinary cases. "I know the sun is shining." "Are you absolutely certain?" "Not absolutely. Memory and perception can be false at times. But I'm happy to insist that I know this fact nonetheless."

If we ground our logic in self-evidence or in intuition, . . . — Banno

I think we should preserve @Janus' distinction between self-evidence and intuition. The standard logical forms are arguably self-evident in the way you describe: "To understand the operator "⊃", is to understand that if p and p⊃q, then q. Asserting p and p⊃q counts as asserting q." Let's say that this is so, and that "self-evidence" is a good-enough way to describe this. Then we want "intuition" to mean something else, something that is not "contained in the premises" or "understanding a language game."

But this, I would say, is no longer a matter of grounding logic. I agree with everything you say about the necessity of grounding logic in shareable, normative principles. (And this also agrees with your claim that "[Intuitions are] a pretty poor grounding for the whole of rationality.") But this seems very different from saying, "I intuit that so-and-so is a good job candidate" or "I intuit that my interpretation of my dream is correct." "Intuition" may be an awkward stand-in for some other process, but at any rate it's not the same thing as pointing to logical self-evidence or unquestionable first principles of rationality.

So, you [@Tom Storm] have rightly drawn attention to the fact that intuition is not one simple kind of thing at all. — Janus

Right, but how we want to discriminate them and evaluate them is not obvious. The suggestion here seems to draw the line between some ordinary accumulation of experience which is shareable, more or less, with others, versus an esoteric metaphysical/religious insight which isn't produced by any kind of accumulation of experience, but is strictly personal. In short:

Intuitions which are based on accumulated experiences and prior processes of reasoning are different than intuitions about gods or metaphysical ideas. — Janus

Devotees of various religious traditions and practices would certainly find this odd. The whole point about such ways of life is that they are based on accumulated experiences, both personal and collective. But I won't try to argue for that here.

They may even feel that what they intuitively know is an absolute or objective truth, but none of this can be anything more than faith-based, and as such not susceptible of rational justification. This seems to be very hard to accept for those who think this way. — Janus

The key phrase here is "not susceptible of rational justification." That is so. But see above. What allows us to insist that rational justification, based on self-evident principles perhaps, is the only legitimate means to achieve intersubjective agreement? Two things about this: First, it's a preference that is deeply rooted in doing philosophy at all, and one that I share. I like things to be rational and intersubjectively justifiable! Most of what I philosophize about falls into this category. But it is not the entire compass of knowledge. Second, it is surely true that dogmatic folks get annoyed when others don't accept their intuitions, especially if they believe they can give a good rational account of them. So much the worse for dogmatism. But it's equally true that many folks (lo, even on TPF :wink: ) find it very hard to accept the idea that rational justification is not necessarily the only gate to wisdom.

This gets us to the problem of how an intuition, no matter how firmly held by the individual, might be justified intersubjectively. I'll pick a low-voltage example, one that doesn't raise hackles about religion or metaphysics. Last night, let's say, I dreamt about crashing my car, which in the dream was an Aston Martin. I've never owned such a car. Upon awakening, it isn't immediately clear what the dream signifies. I'm aware, though, that I frequently use cars, both waking and dreaming, as a symbol for "my life" or "my life direction." And now I experience a flash of insight, an "intuition." Many years ago, I was married to a British woman and looked forward to moving there with her, and restarting my life there. But the dream, and the marriage, failed, to my great sadness. So the crashing of the Aston Martin was a concise image for the death of this particular hope, which my psyche has yet to fully accept. (Please pardon the dash of autobiography.)

So . . . what is the status of the truth claims involved in this intuition? For my part, I know this interpretation is correct. (I'm not absolutely certain, though, as explained above.). The knowledge relies on the idea that a dream may indeed be interpreted correctly. I think that if someone wanted to challenge my intuition, they'd want to do it at that level, by questioning the idea of interpretation tout court. But if it's granted that dreams have meanings, then my intersubjective audience is likely to also grant me my knowledge of what the dream means to me. So let's call this an example of intuitive knowledge. There is no rational process, no empirical investigation, no analysis of self-evidence -- I simply know.

Now obviously I wouldn't try to convince you that, if you had this dream, it would mean the same thing to you. But I do want to convince you that you should trust my interpretation of my own dream. But wait -- it isn't intersubjectively verifiable, and my access to the dream itself is privileged. Why, then, am I unlikely to get an argument about this (except, as I said, at the level of interpretation per se)? Because, if I'm perceived as a trustworthy, sensible, and self-reflective person, you'll take my word for it. This is a meager result for a longish argument, but I really do think it gets to the heart of it. We accept the cogency and validity of intuitions to the extent that we trust the person who has them.

This is not the end of the argument, by a long shot, because the stakes involved in dreams versus faith in a god are enormously different. But that's enough out of me for now.

You seem to be trading on an equivocal idea of intuition. Self-evidence obtains when something is true by definition. We don't need intuition to see it, it is obvious by virtue of the meaning of the terms. If you make a statement that contradicts itself, it is clear that you haven't asserted anything because you have asserted two things which cancel each other out.

I'll agree that there are multiple notions of "intuition" and "understanding" that are unhelpfully related but distinct. I was referring to "what is self-evident," which is often attributed to "intuition" because it does not rely on discursive justification, but is rather the starting point for discursive justification (and in some philosophy, also its ending point).

I don't know if I would necessarily identify the self-evident with "what is true by definition." If one takes "definition" in the Aristotlian sense (i.e., things have a proper definition), then definitions are generally not self-evident, whereas if one takes more nominalist accounts, then the definition might be nothing more than stipulation (which must be empirically arrived at, and so is not self-evident either).

Maybe I should have said "intellectus," but I don't think many people are familiar with that term.

We can theorize further and posit noesis, direct knowledge, innate intelligibility and so on, but we have no way of testing those theories.

True, but this is equally the case for the opposite claim that reason is nothing but discursive ratio/computation. And it faces the problem of being wholly unable to explain the phenomenological aspects of understanding and knowledge (hence eliminitive materialism), nor how "something computes so hard it begins to have first person experiences and understanding." So too for the symbol grounding problem, the Chinese Room, etc.

More radical forms of empiricism start from the presupposition that the phenomenological side of cognition is "off limits," but when this has tended to bottom out in either the denial of consciousness (eliminativism) or the denial of truth and almost all forms of knowledge, one might question if empiricism has become self-refuting at this point (or at least proven to be a bad epistemology). At any rate, even empiricists tend to accept that empiricism is not justifiable in the terms of empiricism. But the difficulty here is the tendency for there to be equivocation between "empiricism" as any observation and experiment at all (in which case the Scholastics and even the Neoplatonists are "empiricists) and the more radical tradition coming out of Hume and continuing in logical positivism, etc., which is used to argue that rejecting "empiricism" is tantamount to rejecting "science and the scientific method," even though plenty of famous inventors and scientists have rejected the more radical philosophical school, but not "science."

Such a trivial logic would, by the very fact that no one agrees with it, have the singular misfortune of being quite unless.

Why does no one agree with it? You seem to be saying that trivial logics are useless just because no one accepts them, but then this leaves totally unexplained how the choice of logic is made in the first place. Presumably, the world did not begin populated by people, with certain logics already popular or not popular.

How would it be "useful" to affirm anything and everything that can be expressed just in case other people also agreed to do the same? There seems to be obvious problems with this.

Rather, I'd say that trivial logics are unpopular because they are useless. People's preferences for different logics have to do with how they represent being.

I threw intuition and self-evidence in together simply out of laziness. They both fall to the criticism I set out, that if someone says that they do not see modus ponens as intuitive or self-evident, then there is no recourse left. However on the - what will we call it - status function account? - there is a recourse: you haven't used modus ponens the way we do. You've done it wrong. Notice that this is the same answer we might give a child who adds seven and three and gets eleven.

It might be argued that this still relies on an authority, and that may be so, but it is at least a more distributed authority.

I'll add that intuition is fine in other situations - when judging a personality, or picking a path, or what you will. Notice that it is idiosyncratic even there: if challenged, can you justify picking this individual or that path? And here we have to share criteria; or perhaps conveniently our intuitions coincide.

The piece of autobiography displays laudable self awareness. I might be inclined to call your interpretation an insight rather than an intuition.

Non of this should be taken to detract from the import of intuition, nor to the respect in which it ought be held.

There's an approach to logic - and rationality - that supposes there are foundational propositions from which it is built, that justify everything that follows. Logic is seen here as a hierarchy; the epitome being axiomatic constructions. This fell into disfavour in the eighties, replaced by natural deduction, sequent calculus and such. Gentzen-style. I was taught, and indeed have taught, both approaches. Justification in the newer approach is contextual, dialogical, and structurally horizontal, focusing on rules of inference rather than axioms. Logic became more dynamic — a tool for reasoning, not a blueprint for metaphysical truth.

This lead to a picture of logic not as a hierarchy so much as a network, and to a pictures of justification not in terms of foundations but in terms of coherence.

This directly parallels the differences being played out here. At the risk of taking us back to the topic of the tread, we have those who see a need to find some absolute immovable foundation for what is real, and those who see what is real as grounded in context and action, in what we are doing.

Why does no one agree with it? — Count Timothy von Icarus

A trivial logic might begin with p^~p, from which everything follows. Formally, it's complete and consistent, but utterly unable to help us in deciding what is the case and what isn't. Go ahead and agree with it, if you like. It won't get you far. In such a trivial logic, everything is the case. That's why we don't use them, and why (almost?) no one agrees with them. But it seems we agree that they are useless. pv~p is much more interesting.

This is an example of how the choice of logics might be made. Pick one that does the job you want done, or that will extend and enhance the conversation.

Still we will continue to ask the question, what is real? With good reason and what is real will continue to slap us in the face, or stare back at us in the mirror.

I might be inclined to call your interpretation an insight rather than an intuition. — Banno

Consistent with recommendations I've made before, I'll say that I'm fine with either "insight" or "intuition" here -- and perhaps everywhere that "intuition" is used. The term is less important than what it's trying to capture. What I notice about the dream example is that it's about meaning -- a very special class of knowledge. Hermeneutics rather than factual truth. Might it be the case that this is how intuitions (or insights) gain their validity? We do want to say that we can know what something means. Is such knowledge intersubjectively valid?

Logic became more dynamic — a tool for reasoning, not a blueprint for metaphysical truth. — Banno

This brings up what seems to me a deep question, raised recently by Kimhi and others: What is the overlap between logic and the world (including, if you don't mind, metaphysics)? If we commit to a certain understanding of normative logic, must we also commit to some parallel truth about the world, whether metaphysical or everyday? Can 'p' equally refer to both a sentence and an object? Must it? In short, can logic really be just a tool rather than a map?

I'm agnostic on this question. But we can see how different answers to it will give rise to important differences in how we view the connection of mind and the world. Oddly, the sea-battle debate taking place over on the "Demonstrating Intelligent Design . . . " thread exemplifies the same question: Should a commitment to semantics, or logic, dictate what we say about the future, understood ontologically?

I'm agnostic on this question. But we can see how different answers to it will give rise to important differences in how we view the connection of mind and the world. — J

Wittgenstein pointed out that we can't know the answer, but he admitted that he couldn't resist being pulled back into questions like that. What's driving us to speculate?

I'm now not sure where you stand. You seem to be defending intuition in other areas - your dream being a case in point. And that's fine. Do you still think that intuition is enough to justify acceptance of logic?

I'll try to put this in as stark a contrast as I can. We all accept modus ponens. Is it, on the one hand, that we accept that if the antecedent and the conditional hold, then we intuit that the consequent also holds? Or is it that the accepted use of antecedent, conditional and consequent is that if the antecedent and conditional hold, then the consequent holds? Is logic to be grounded on private intuition or public practice?

And he argument I gave earlier seem to show that a private intuition cannot serve to ground logic in the way we may want.

Or perhaps you think that your intuitions correspond to the public practice?

What is the overlap between logic and the world — J

If, as I suspect, we hold to modus ponens not becasue it is self-evident or intuitive - although it may be both - but instead becasue it is what we do, then the overlap between logic and the world is that logic is a grammar for our talk about how things are.

So we might have instead chosen a grammar in which both a p and ~p are true, but then while our language would have been coherent, anything could be both true and false. Such a language would not be of much use.

So instead we choose languages in which p is true, or ~p is true, and not both. This gives our conversations quite a bit more traction.

And to this we can add some complexity. That's when we start to study logic.

Now we might be tempted to ask why p v ~p is so much more useful than p ^ ~p. But isn't one answer here just that we can do more with it? That it is more useful becasue it is more useful? That is, if instead we accepted p ^ ~p, we would not be able to have this conversation?

Asking why p v ~p and not p ^ ~p is like asking why the bishop stays on it's own colour, or why putting the ball in the net counts as scoring a goal. It's what we do.

Wittgenstein pointed out that we can't know the answer, but he admitted that he couldn't resist being pulled back into questions like that — frank

Did he? I'm not so sure. Where did he say this?

I've a lot of sympathy for the stickiness of philosophical problems. Seems I keep allowing myself to be drawn into the same issues. But what exactly was it to which he said we cannot know the answer? Was it really "can logic really be just a tool rather than a map?"

Becasue I think I've given a roughly Wittgensteinian answer here, after the spirit of PI §201, and with a bit of Austin, Searle and Davidson thrown in.

Do you still think that intuition is enough to justify acceptance of logic? — Banno

No. Maintaining the distinction between self-evidence and intuition, I think that e.g. modus ponens is self-evident but not intuitive. No further act of interpretation, such as described in the dream example, is needed to arrive at 'q'.

The problem remains about how this connects logic with the world. What is modus ponens self-evident about? Thought, or the world? I think this is still a problem even if you replace self-evidence with "it's what we do." Are we "doing it" with propositions or with objects?

logic is a grammar for our talk about how things are. — Banno

Indeed it is.

Now we might be tempted to ask why p v ~p is so much more useful than p ^ ~p. But isn't one answer here just that we can do more with it? That it is more useful because it is more useful? — Banno

I'm not sure that qualifies as an answer, even generously. Unless usefulness is an unanalyzable bedrock?

Asking why p v ~p and not p ^ ~p is like asking why the bishop stays on it's own colour, or why putting the ball in the net counts as scoring a goal. It's what we do. — Banno

This separates the Witts from the NitWitts. :wink: A NitWitt like me (on this particular topic) will deny that bishops and goals are good analogies for what p v ~p is. But as you know that's a long and intermittently fascinating discussion -- probably not for here.

I'm not sure that qualifies as an answer, even generously. — J

It's not so much an answer as an attempt to show how the question misfires.

You seem to be in the position of someone who asks how it is that their key just happens to fit their front door and no one else's.

Good one! And in a funny way, that is what I'm asking. It seems too good to be true -- not that the key fits, but that I find myself with that particular key to hand. End of story? Hmmm (frowns suspiciously).

I'll pick this up again tomorrow (USA).

I'm not sure that qualifies as an answer, even generously. Unless usefulness is an unanalyzable bedrock?

I've asked this question to @Banno many times and never received anything but deflection. His notion of use seems to bottom out in a sheer voluntarist will. The need to speak to any causes of this "usefulness" is some sort of pseudoproblem, for vague reasons. Apparently, any logic or notion of truth is "useful" just because others are "playing the same game." Yet this doesn't seem true. If everyone told you that commonly accepted logic proved that jumping off the Brooklyn Bridge would make you immortal, and you saw them jumping off the Brooklyn Bridge, you'd still be stupid for following them.

For instance :

Now we might be tempted to ask why p v ~p is so much more useful than p ^ ~p. But isn't one answer here just that we can do more with it?

"We decide" if a frog can be both living and not living at the same time based on how useful this is to us? How this position would not result in an all encompassing relativism is beyond me. Nothing grounds logic or truth except the bare assertion of "usefulness" and a sort of appeal to democratization. How the bishop moves is somewhat arbitrary. You can make a chess variant where it moves differently. Can you make a frog be alive and not alive by having a language community agree to speak of it in certain ways? No doubt it would be useful to have one's cake, to not eat it, and to eat it to. It's just that this is impossible regardless of how useful it would be.

Nor does it make much sense that a frog could be both alive and not alive just in case we find it useful for the frog to be such. Seems to me it'll either be dead or alive without much regard for our uses.

I've asked this question to Banno many times and never received anything but deflection. — Count Timothy von Icarus

I answered the question quite directly. appears to see this. You insist on misrepresenting that answer. "We decide if a frog can be both living and not living at the same time based on how useful this is to us" has nothing in common with what was suggested.

If I'm misrepresenting you, surely you can lay out what determines usefulness then.

This:

This is an example of how the choice of logics might be made. Pick one that does the job you want done, or that will extend and enhance the conversation.

Leaves "use" as an unanalyzable primitive. And a trivial logic absolutely can be "used" to do all sorts of things. It can be used, for instance, to prove that if a frog is alive it is also not-alive. That's a use. Some people don't want to "enhance conversation." They find domination and power most useful. Does logic and truth conform to this use as well?

What I'd maintain a trivial logic cannot do, is conform to what is actually true, which is the point of logic, not some amorphous "usefulness." If usefulness instead of truth grounds logic, what you have is relativism based on whatever is felt to be useful (more Nietzschean then where Wittgenstein was going if you ask me).

If I'm misrepresenting you, surely you can lay out what determines usefulness then. — Count Timothy von Icarus

Usefulness isn't determined by some rule. That's kinda the point.

Pick one that does the job you want done, or that will extend and enhance the conversation.

If we do not accept that the frog can be both alive and dead, then a logic that allows this is not suitable.

No, I think "absolute certainty" as a synonym for "knowledge" is way too high a bar. I have in mind the same criteria for knowledge we'd use in the ordinary cases. "I know the sun is shining." "Are you absolutely certain?" "Not absolutely. Memory and perception can be false at times. But I'm happy to insist that I know this fact nonetheless." — J

I've always liked to draw a distinction between being able to be absolutely certain and feeling absolutely certain. I think it's possible that people can feel absolutely certain about something they cannot be justified in being absolutely certain about. So, I was referring to feeling absolutely certain in the bit you responded to above. Given the possibility of radical (if not global) skepticism, it can be said that we cannot be 100% justified in being absolutely certain about anything at all.

Right, but how we want to discriminate them and evaluate them is not obvious. The suggestion here seems to draw the line between some ordinary accumulation of experience which is shareable, more or less, with others, versus an esoteric metaphysical/religious insight which isn't produced by any kind of accumulation of experience, but is strictly personal. In short:

Intuitions which are based on accumulated experiences and prior processes of reasoning are different than intuitions about gods or metaphysical ideas.
— Janus

Devotees of various religious traditions and practices would certainly find this odd. The whole point about such ways of life is that they are based on accumulated experiences, both personal and collective. But I won't try to argue for that here. — J

The problem is that my "ordinary accumulations of experience cannot be obvious to anyone else, so I think my intuitions about something like choosing intuitively who to hire as @Tom Storm gave as an example does not seem to offer any cogent justification for my believing his choice was correct unless I had my own accumulated experience that showed a substantial history of his good judgement of character.

I don't understand metaphysical ideas and religious beliefs to themselves be accumulated experiences, even though they may be believed to be supported by experiences, and also to give rise to experiences. So, in other words the belief in the existence of God or that some metaphysical thesis is the true one are not experiences, but may be held on account of experiences, and in turn give rise to experiences.

I'll agree that there are multiple notions of "intuition" and "understanding" that are unhelpfully related but distinct. I was referring to "what is self-evident," which is often attributed to "intuition" because it does not rely on discursive justification, but is rather the starting point for discursive justification (and in some philosophy, also its ending point).

I don't know if I would necessarily identify the self-evident with "what is true by definition." — Count Timothy von Icarus

What is logically self-evident is that, for example, if you say something that contradicts itself, that is made contradictory assertions, then you have not really made an assertion. As I said earlier, it's like saying 'yes' and 'no' at the same time. If you say to me, do you want to go for a coffee, and I say " yes I want to go for a coffee, no I don't want to go for a coffee" how will you know whether I want to go for a coffee? We don't need intuition to see that.

We don't need intuition to know that something cannot be all white and all black all over; nothing we have ever perceived has been like that, and what something like that would look like is unimaginable; it obviously could not look all white or all black or both.

That 2+2=4 is self-evident on account of the meaning of the words and the fact that we can hold up two fingers, and then two more fingers, and see four fingers.

Maybe I should have said "intellectus," but I don't think many people are familiar with that term. — Count Timothy von Icarus

'Intellectus' is a more equivocal term that 'intuition' so I don't think that well help.

True, but this is equally the case for the opposite claim that reason is nothing but discursive ratio/computation. And it faces the problem of being wholly unable to explain the phenomenological aspects of understanding and knowledge (hence eliminitive materialism), nor how "something computes so hard it begins to have first person experiences and understanding." So too for the symbol grounding problem, the Chinese Room, etc. — Count Timothy von Icarus

Reason is simply consistent thinking. You start with premises, and then work out what they entail. Intuitions are not generally based on this kind of reasoning, but are more "gut feelings". I think attempts to explain things like the quality of personal experience are misguided; seeking to do that involves a category error. Our explanations are given in terms of causes and conditions, or personal reasons, and it seems impossible to explain qualities in either of those ways. Think, for example, about trying to explain beauty in terms of causality or personal reasons.

More radical forms of empiricism start from the presupposition that the phenomenological side of cognition is "off limits," but when this has tended to bottom out in either the denial of consciousness (eliminativism) or the denial of truth and almost all forms of knowledge, one might question if empiricism has become self-refuting at this point (or at least proven to be a bad epistemology). At any rate, even empiricists tend to accept that empiricism is not justifiable in the terms of empiricism. — Count Timothy von Icarus

It's not surprising that empirical reasoning cannot be explained in terms of empirical reasoning, because empirical reasoning is about predicting from observed patterns and regularities as to what will be observed and/ or inferring what must be the case. It relies on the whole accumulated body of practical knowledge and wisdom and science. Why would we need to explain it if it works? Why should we seek to explain it if the desire for an explanation is misguided?

So if you were to disagree with someone's intuition, not to share their intuition, they have no comeback. It's difficult to see how not having an intuition is something you can be wrong or mistaken about. i think we agree on this. It's a pretty poor grounding for the whole of rationality. — Banno

But couldn't we say that intuition and self-evidence are signs of, or of a piece with, our practices? It just doesn't seem all that far from saying "they would not be participating in the same activity" to saying they would not have the intuitions—the experience of the agreement of logic with what we do—that people have when they successfully do x and y.

Granted that to say intuition is the ground is too strong, but isn't it also too strong to say that intuition as ground is entirely off the mark?

Usefulness isn't determined by some rule. That's kinda the point.

Or apparently by anything more distinct than "what I currently desire." But logic involves what is true, so this makes truth simply a consequence of whatever one desires.

If we do not accept that the frog can be both alive and dead, then a logic that allows this is not suitable.

Conversely, if we do accept it, then such a logic would be suitable? So logic has to do with our current beliefs, and whatever we feel. But then discursive reason isn't about truth; it comes down to desire, feeling, and thus ultimately to power.

Everyone agrees about the often contradictory truths announced by the state in 1984. They all play the same language game. To not play is made not useful; it's double-plus ungood. But that doesn't make the game's truth claims true.

Reason is simply consistent thinking. You start with premises, and then work out what they entail.

This is just a restatement of "reason is nothing but discursive ratio" without addressing any of the problems it entails (mentioned in the post you are responding to).

For one, you note that we must "start with premises" to have reason at all. So, are our initial premises about entailment itself irrational because we must begin with them? Are they outside reason? Is all of reason based on unjustified (and unjustifiable) starting points then?

Again, give me a discursive argument while assuming absolutely no inference rules. You can't, by definition. Without assuming that some things follow from other things there is nothing to link one assertion with another, and all you have is a bare posit. If reason is just discursive rule following, then such starting points aren't rationally justifiable and you get something like the appeal to bare "usefulness" above.

"Logics" without LNC exist. Trivial logics that allow us to both affirm and deny anything expressible exist. Explosion exists. If reason is just rule-following, then there is nothing unique about LNC, it's just another rule that can be asserted or not asserted, with consequences for the structure of whatever "game" we are playing.

I'd allow that LNC is self-evident. But for something to be self-evident requires that there be a non-discursive grasp on truth. Your justification for denials of LNC not making sense above are straightforwardly circular for instance. They have to assume what they set out to prove.

Either not all justification is discursive (some things are self-evident, and known non-discursively, e.g. what has often been meant by intellectus in this context), or all justification ultimately rests on unjustifiable and unknowable assertions.

The problem is that my "ordinary accumulations of experience cannot be obvious to anyone else, so I think my intuitions about something like choosing intuitively who to hire as Tom Storm gave as an example does not seem to offer any cogent justification for my believing his choice was correct unless I had my own accumulated experience that showed a substantial history of his good judgement of character. — Janus

I meant to suggest something similar, when I wrote about the trustworthiness of people's intuitions. Your intuition about the job candidate is private and, in an extreme case, unjustifiable to anyone but yourself. But my choice to trust your intuition can be justified fairly easily -- again, not with any absolute certainty.

the belief in the existence of God or that some metaphysical thesis is the true one are not experiences, but may be held on account of experiences, and in turn give rise to experiences. — Janus

Yes. This takes us to the question of meaning, of interpretation. My sense is that those who are firmly opposed to the idea of religious or mystical experiences believe that no conceivable interpretation of experience that include references to godlike entities could be correct. That, I'm sure we both agree, needs independent argumentation.

If we do not accept that the frog can be both alive and dead, then a logic that allows this is not suitable. — Banno

Conversely, if we do accept it, then such a logic would be suitable? — Count Timothy von Icarus

I think you two are trying to formulate an answer to the question I keep posing: What is the LNC about? What is it a law of? What domain does it govern? What can fill in 'p'?

I don't want to interrupt your conversation, which perhaps you find fruitful, but you might take a stab at answering -- or dissolving -- that question, tentatively. I'll expand this in a subsequent reply to @Banno about the suspicious key that fits my lock.

What is the LNC about? What is it a law of? What domain does it govern? — J

I'd suggest it is a law about use of language which is truth preserving.

I'd also suggest that there are patterns to language which preserves truth; the neural networks in our brains recognize such patterns, resulting in our intuitive recognition of the LNC as truth preserving.

PNC can be formulated as a metaphysical, epistemic, or semantic principle. Ultimately, the latter will tie back to the former if the former is affirmed because being (existence) is prior to being experienced and being spoken about.

As a purely logical principle, it might be considered normative, in that it would not be rational to affirm what is necessarily impossible, though no doubt people can affirm all sorts of things (whether they can actually believe them is another matter).

As a metaphysical principle, it might boil down to the idea that being and not-being, existence and non-existence (in any determinant form we might signify or think about anything) are exclusive. They are exclusive because if being and non-being could be the same, things could both have and not have determinant existence, be both something and nothing, collapsing the most basic of all distinctions that allow anything to be any particular thing at all.

The metaphysical principle is not primarily about truth then, nor affirmation and negation. Truth has to do with the relationship between the intellect and being. We do not say of a rock or tree that it is "true." Rather, things said or thought about rocks or trees are true. The metaphysical principle is about being (which obviously has a close relationship to truth since anything that is truly is).

I'd suggest it is a law about use of language which is truth preserving.

If nothing truly is and is-not, then this is necessarily so. One cannot preserve truth while affirming something that is never true. But it is never true that something is also nothing, that existence is non-existence, that being is non-being, etc.

The difficulty here is that it is absolutely true that we might think we have identified contradictions where there are none. There might be qualifications and distinctions that dissolve apparent contradiction. But no qualification or distinction can dissolve "something is also nothing" and "existence is also non-existence." This is basic.

Now we might be tempted to ask why p v ~p is so much more useful than p ^ ~p. But isn't one answer here just that we can do more with it? That it is more useful because it is more useful? — Banno

I'm not sure that qualifies as an answer, even generously.
— J

It's not so much an answer as an attempt to show how the question misfires.

You seem to be in the position of someone who asks how it is that their key just happens to fit their front door and no one else's. — Banno

In a funny way, that is what I'm asking. It seems too good to be true -- not that the key fits, but that I find myself with that particular key to hand. — J

OK. Deep breath. No, I don't think your response is a deflection, as @Count Timothy von Icarus is suggesting. When a philosopher believes that a question is a not a good one -- that there is no answer that can be meaningfully given, because it doesn't discriminate between two genuine alternatives -- it's often hard to show this. Telling a little analogical story can help. Witt of course was the master of this.

So, faced with a question that you think is defective, you ask me to imagine myself puzzled about why my housekey fits my door, and only my door. Very well. Imagining this, what might puzzle me? It could be two things: I might ask, "Why does this key uniquely fit my door?" or I might ask "Why do I happen to have this key?"

Now I think what I'm supposed to imagine next is that both questions get an explanation or a deconstructive answer that can resolve my puzzlement. To the first question, the reply is, "Because that's what 'your housekey' means. You can't have 'your housekey' without it having both those attributes: it fits your lock, and only your lock. So if you understand 'your housekey', there is no further question to be asked about it." To the second question, the reply is, "Because that's how an object comes to be yours: you possess it, it's been made for you and given to you. Also, since it's an important object in your life, you'll have it to hand, and shouldn't be surprised that this is the case. Are you still puzzled about why you live in a world in which all people fortunate enough to be housed have keys? You just do; that is your world; there's nothing special about you."

Being a philosopher, I can make trouble for both these replies, but I don't really want to. On the whole, they're reasonable, as an account of the keys-and-locks "game." But I challenge whether the story is analogical to my questions about logical primitives.

(p v ~p) appears to fit -- to "be the key" -- to two types of phenomena. It appears to be a law of thought, perhaps normative, perhaps transcendentally descriptive, perhaps psychological, depending on how we rate Frege. It also appears to describe necessary facts about objects in the world, all things being equal. My puzzle is: How is it that these are two phenomena, which resemble each other so closely yet have such different objects? Or am I wrong about that? Must I simply accept that the "key" of logic fits the "lock" of the world? Is it the case that, just as you can't have "my housekey" without understanding "my uniquely fitting key", you can't have (p v ~p) without understanding "our description of the world" or perhaps "what we do, talking about the world"?

It's interesting that both the time-honored view of mind as reflecting the structure of reality -- a "unique fit" if there ever was one -- and the contemporary Witt-based view that questions about the relation of mind and reality are defective, aim at resolving the same question, the question I'm posing. I don't find either view persuasive on the merits. Both attempt to dismiss the question at a bedrock level. Each finds its "spade turned" at the idea that this just is how it is, though I think most earlier versions would postulate God as the reason.

I don't think what I've just written is a satisfactory rebuttal to the analogy of the locks and keys. I would need to say more about what makes logical items like (p v ~p) hold up under the deconstructive dismissal I've described. But for now, I just want to give a picture of how I see the question. If you want to correct my versions of how the question might be said to misfire, please do; I don't want to waste anyone's time with straw-persons.

Now I think what I'm supposed to imagine next is that both questions get an explanation or a deconstructive answer that can resolve my puzzlement. To the first question, the reply is, "Because that's what 'your housekey' means. You can't have 'your housekey' without it having both those attributes: it fits your lock, and only your lock. So if you understand 'your housekey', there is no further question to be asked about it." To the second question, the reply is, "Because that's how an object comes to be yours: you possess it, it's been made for you and given to you. Also, since it's an important object in your life, you'll have it to hand, and shouldn't be surprised that this is the case. Are you still puzzled about why you live in a world in which all people fortunate enough to be housed have keys? You just do; that is your world; there's nothing special about you."

But that isn't what "your house key" means. If someone changes the locks on my door while I'm out, my key doesn't cease to be mine. And if I bend the key, it won't turn the lock, even though it is still the same key and the same lock. Nor do we possess keys "because we just do." The fact that you have a key in your pocket and whether or not it fits your door has intelligible causes. If we allow "why does my key turn my lock?" to become an aporia, then what won't be?

This is, IMO, simply a bad analogy. Chess is not a good analogy for logic and truth. House keys aren't either. Not all analogies are appropriate. This is all I mean by "deflecting," the move into seemingly only tangentially related and wholly unjustified analogies.

They resemble each other so closely yet have such different objects? Or am I wrong about that? Must I simply accept that the "key" of logic fits the "lock" of the world? Is it the case that, just as you can't have "my housekey" without understanding "my uniquely fitting key", you can't have (p v ~p) without understanding "our description of the world" or perhaps "what we do, talking about the world"?

What would it mean for them to have different objects? It would mean that thought is arbitrarily related to reality as far as I can tell. How could anyone, ever, justify such a claim? A reality versus appearance distinction can only have content if there is something more than appearances. If there are only appearances (thought), then appearances are reality. Whereas, if reality is arbitrarily, randomly related to appearances then you don't really have one sort of being that encompasses both sides of the reality/appearance distinction, but two sui generis, unrelated "types of being." Appearances would be their own, discrete sort of being.

Now let me ask, why should we posit any sort of unique, sui generis being that is unrelated to any thought or experience anyone has ever had, or could ever have?

If reality, the actuality of things, does not determinantly affect thought, it isn't worthy of the name. It's just some irrelevant, arguably incoherent bare posit.

PNC can be formulated as a metaphysical, epistemic, or semantic principle. — Count Timothy von Icarus

OK. So you're saying that, as it happens, it applies to three areas or types of phenomena. Or would "types of activity" be better? I don't want to put words in your mouth.

Ultimately, the latter will tie back to the former if the former is affirmed because being (existence) is prior to being experienced and being spoken about. — Count Timothy von Icarus

"Tie back" raises the problem once again. Why does it do so? In what way? The priority of existence to human experience wouldn't guarantee the fidelity of our descriptions of that existence. Why does the key fit?

I think what you're saying is that PNC is a principle both of thinking and of being, full stop. It (and its cousins in the P family :smile: ) is what we mean by "truth", mean by "exist". But if that is all that can be said, then shouldn't you agree with @Banno and Witt? Further questions about how or why this is the case would be ill-formed.

In other words, your classification of the ways we perceive and use PNC may be quite accurate, but it leaves untouched my question about why, about what grounds what. See my reply to @Banno above: How is it the case that the world, and our experience of it, is so structured? Does the PNC and its cousins represent spade-turning principles about both thinking and being, in the same way, and for the same reasons?

But that isn't what "your house key" means. If someone changes the locks on my door while I'm out, my key doesn't cease to be mine. And if I bend the key, it won't turn the lock, even though it is still the same key and the same lock. — Count Timothy von Icarus

Hmm, I dunno. In the first case, it's no longer my house key, though it is still mine. And in the second, calling it "the same key" is equivocal; it isn't really isn't a key any more at all.

If we allow "why does my key turn my lock?" to become an aporia, then what won't be? — Count Timothy von Icarus

Oh, I agree. I don't want it to be aporetic at all. It's just a hard question to answer, when the analogy is extended to logical primitives.

What would it mean for them to have different objects? It would mean that thought is arbitrarily related to reality. — Count Timothy von Icarus

I don't see why. Why must the difference be arbitrary? If anything, my puzzlement postulates the opposite: that it isn't arbitrary, that there ought to be some explanation. But you can't deny that a rock and a proposition are extremely different items.

If reality is arbitrarily, randomly related to appearances . . . — Count Timothy von Icarus

Again, you're reading way more into my position than I intended. Arbitrariness and randomness are not the only alternatives.

. . . unrelated to any thought or experience anyone has ever had, or could ever have? — Count Timothy von Icarus

And again. Why puff it up in this way? No one, least of all me, is saying anything like this.

There are hierarchies of distinctions. Distinctions like act/potency or part/whole are more general than any particular science (e.g. physics, logic, mathematics, etc.). It seems to me that nothing could be more general than being/existence.

What is true for the higher level must be true for the lower. What is true of parts and wholes in mathematics cannot be distinct from physics, or physics from biology. If it were, we wouldn't have "science" but a great multitude of unrelated sciences, and no rational way to demarcate different sciences.

"Tie back" raises the problem once again. Why does it do so? In what way? The priority of existence to human experience wouldn't guarantee the fidelity of our descriptions of that existence. Why does the key fit?

See the post above. Just think through what it means to say that thought is not determined by being in any determinant way. You would be posting a distinction between thought and "objective reality," but then be saying "but maybe objective reality has no determinant effect on thought." This undercuts the distinction itself, rendering it contentless.

A realm of thought alone with random causes would be identical to a realm of thought influenced randomly and indeterminately by some extrinsic "realm of reality." Nothing would connect the two.

How is it the case that the world, and our experience of it, is so structured? Does the PNC and its cousins represent spade-turning principles about both thinking and being, in the same way, and for the same reasons?

I don't think there is any spade turning at all. All that is required is to affirm the priority of actuality over potency. Something actual (determinant) must move the mind from potency to actuality—must move it so that thought is one way and not any other. To deny this would be to say that thought occurs "for no determinant reason at all." This severes any real connection to a "being prior to thought," while also rendering the world unintelligible and philosophy ultimately pointless.

But the world doesn't seem unintelligible. At any rate, at the end of the day being is either intelligible, and things do happen for reasons (act is prior to potency) or it isn't. If it isn't, all philosophy is wrong. Things can be any way at all.

.

A bent key is no longer a key? And if you can bend it back it becomes a key again I suppose? Come on, the analogy doesn't make any sense.

Oh, I agree. I don't want it to be aporetic at all. It's just a hard question to answer, when the analogy is extended to logical primitives.

It's hard because it isn't a good analogy.

Why does my key turn my lock? Because it fits in, lifts the pins, and gives me leverage to turn the deadbolt.

And again. Why puff it up in this way? No one, least of all me, is saying anything like this.

Because this is what the denial of the primacy of actuality (the priority of determinant being) to potency entails. It means that potency moves itself to actuality "for no reason at all," due to no prior actuality. This means things do not have causes or reasons.

Either the mind is moved to actuality by prior actuality (by determinant properties of being) or it isn't. If it isn't, then it is moved by "nothing at all" (by nothing actual). Epistemic PNC follows from metaphysical PNC.