I think a lot of people were more interested in shooting down other planes than trying to fly their own. — Leontiskos

It is hardly outside the mainstream to think philosophy's mission might be principally if not exclusively critical. Starts with a guy called 'Socrates' ...

But can you think of anyone other than the OL philosophers whose ideas are not nuanced and subtle? — J

I strongly take issue with OLP not being nuanced. My God, read "A Plea for Excuses." Subtlety, maybe that's a little harder to say. Certainly OLP doesn't usually leave points implicit, or make them only indirectly. But if a subtle point is a small and easily overlooked one, that too is in OLP's wheelhouse.

One funny thing about all this is that you included the word "discourse" in the title. Every time I was writing "philosophical discourse" I wondered whether I couldn't just say "philosophy".

But that's part of the issue here. We want to look at how philosophy *talks* to other disciplines, and how we interrogate that splits: we can look at *how* that works, and @fdrake and I followed your lead there a bit; but we can also look at *why* philosophy talks this way.

The why question also offers two natural courses: this is something philosophy does in reaction to other disciplines; or this kind of interaction is just a natural consequence of philosophy doing what it does, a sort of side effect.

If you want to know what philosophy is, you could just look at philosophy. You would only look at how philosophy interacts with other disciplines if you believed, or hoped, that something about philosophy is clearer in such interactions, maybe something that is hard to see by just examining philosophy directly. (There is a third option, which is the typical sort of comparison, without interaction: philosophy is more abstract, more general, blah blah blah.) And then you look at how philosophy talks to other disciplines to understand how it interacts with them.

You could carry this out without a plan, just to see what you get, but then it's hard to know what you're getting. (Am I looking at a feature specifically of philosophy's interactions with other disciplines, or a feature of philosophy proper? Among other questions.)

I think it might be better to ask first why we might thing the interaction of philosophy and other discipline might be particularly revelatory. What do we expect an examination of those interactions to show?

Heh, more preliminaries!

if he did intend it to be a justificaiton for a state, then it is a rubbish one. — Clearbury

Well, I haven't read him, so I can't fill in the argument, if there is one.

I suppose, though, if you're going to talk about rules at all, then the natural question is whether and how those rules are enforced.

But it doesn't do anything to show the state to be justified. — Clearbury

Does he claim that it does show the state is justified?

Does Rawls call this a "hypothetical contract"? How does he describe it? And how does he use this thought experiment to justify the formation of the state?

I've never read Rawls myself ― was never very interested in political theory.

So I suppose Rawls made certain arguments that you found persuasive until you read Michael Huemer ― is that right? And I expect Huemer addresses Rawls's arguments directly.

Could you give an example of something Rawls says ― especially if it's an argument you used to find persuasive ― that you believe Huemer presents a strong counter-argument to? Like I said, not a field I know much about, so I'm curious.

What were your political views before you encountered Michael Huemer? Were you already interested in politics?

That's the only one I know, so I wasn't sure if he was central to the field. I read that long long ago. He was an OLP guy.

There are two issues here.

One is whether rights are better conceived as natural or positive. You believe natural, but you ought to at least look at the case for treating rights as positive. I don't know whom you should read to understand that view. Maybe someone here knows, or you could Google the usual sources.

The other issue is your central claim about the state. You're familiar with at least one case for anarchism. Another guy to look at would be David Graeber, but there are plenty of others.

And here too, you might consider looking at arguments for the state. There's obviously lots of writing there, but two I can recommend that I find interesting because they're not just theory are Timothy Snyder (whom I quoted on the Holocaust) and Acemoglu and Robinson, Why Nations Fail.

I agree with (almost) all that! @Pierre-Normand had a useful thing about universality and generality that fits here too.

And obviously I have in the back of my mind LW's comments about needing the overview, the birds-eye-view.

What I like is the idea of going up and down @J's ladder. And stepping back doesn't always have to mean going up either. You can also step over to some other part of the garden, and see how things are going there, look for commonalities and differences, but also look for analogies.

I still think there's room to be wary of the intoxication of heights, the seductive power of going up and staying there. Back to the rough ground!

Let's take your first example, the biologist. Here's a simple approach.

You're doing biology, some research, some model building, some reading, etc. You take a step back and reflect on what you're doing and how you're doing it. That's an important step in research and in problem solving. I would be okay with following @Joshs here, I think, in saying this is a "more philosophical" moment, on a spectrum.

But now what? You have a new perspective and some new ideas. Do you get back to work? Step back off the ladder? Or do you take another step up, another step away from research and toward contemplation and reflection? Do you follow up on how that step up can inform and maybe improve your work, or do you find yourself looking out across the landscape, noticing other ladders sticking up here and there, getting interested in them, wanting to get higher so you can see more ladders, because now you're interested in ladders and heights ...

I guess you could call this a different kind of research, so that we don't have to say that philosophy is that form of inquiry that doesn't involve research, but it's a different sort of thing from what people on the ground do, and what you used to do when you were a biologist. And what you're inclined to say about what goes on down there, and about what people are doing who study what's on the ground, it's more and more likely to be bullshit, something that sounds good to you, all alone, a thousand feet above them, when you can no longer see what's down there in any detail.

Lots here. I'll have to do this piecemeal — J

Don't bother. I'm doing some rereading and may have yet another take on all this at some point.

In the meantime, have you considered that you might be misconstruing what you've discovered?

What you describe could also be taken as showing that philosophy is a trap: inquiry is in danger of getting stuck there, no longer producing knowledge. (Which, let's be honest ...)

"Philosophy" may be what we call inquiry that has run off the rails, or gotten stuck in the doldrums, or reached a high point it's unable (or unwilling) to climb down from.

Instead of asking if philosophy is in danger of being dislodged from its perch by any other discipline, maybe the right question is whether any other discipline can come to philosophy's rescue. Are there disciplines that can help you get down, or do you have to jump?

But there is a question of fact about whether the Freudian psychologist is making use of what J would call "philosophical" thinking on order to deflate the philosopher's claim. I think it should be recognized that what the Freudian psychologist sees himself as refuting and what @J sees as "philosophy" are probably two different things. — Leontiskos

Let's say this: the philosopher believes questions of justification are always legitimate and appropriate; the psychologist believes questions of "motivation," say, are always legitimate and appropriate.

If the philosopher believes he's on firm ground demanding to know how the psychologist knows what he claims to know, the psychologist believes himself to be on ground just as firm in examining the philosopher's motives for demanding justification.

Of course each side sees the other as dodging a legitimate question. I do not see philosophy doing anything unique here, just treating everything as a nail, as every other domain does.

And of course there will be philosophical justifications for treating questions of justification as special and uniquely important, but that's just a restating of philosophy's initial position.

The natural move would actually be to engage in internal critique of psychology, to attempt to explain the study of psychology with reference to the motivations of psychologists. The problem is, that's no help if it actually works; you have to hope that psychology is unable to account for itself.

(And suddenly I recall as a teenager snickering at the phrase "inorganic chemists".)

Here's my problem. I'm pretty interested in what I intuit as the substantive issue in this thread. I would like to get to discussing that, and I don't know what I would say ― which for me is a big reason to have that conversation.

But I keep getting stuck on what, in my mind, I'm still treating as "preliminaries," just trying to clear up your framing of the issue. That framing keeps failing to make any sense at all, so I keep putting off getting to the supposed substance, and I feel dragged into this sort of Wittgensteinian suspicion that there is no substance on the other side of the preliminaries, because the issue can't actually be framed cogently.

So here

What I was imagining, and trying to describe, was a refereed situation, so to speak, where each of the interlocutors agrees to the rules of rational philosophical discourse. Playing by these rules, the philosopher always trumps, and always wins. — J

What on earth are you doing? I'm not going to quote the OP, but the initial pitch was for philosophy as the ultimate backstop or bedrock, because philosophy can force any discipline ― or even any claim ― into a philosophical discussion, but once there, any further probing and questioning is just more philosophy. Among the many overlapping ideas in this setup was that philosophical ideas are simply impervious to any but philosophical counters.

If the bearded Viennese tries his "Interesting. Do you always . . . " response, the referee steps in and says, "Out of bounds. Please answer the question." — J

Only now it turns out you don't intend to show that this is so, but enforce it, by fiat. You just define the discussion as philosophical from the start. No effort or super-power needed from philosophy, and if you try to respond to my philosophical questioning with economics, say, I'll just rule you out of bounds.

What the hell?

This is like brothers fighting about a game ― one finds something easier than the other, so the other keeps complaining, "No! You're not doing it right!" It's hard for me, so it has to hard for you, or you're cheating.

You may recall that I wondered who even bothers to challenge philosophy. Here's one reason. Philosophers decide that they get to make the rules, interpret them, and enforce them. Yay! Can I play too? ― Most people are just gonna say, "Go run your little world." (( Counting on you to get that one, @J. Fuller version, from memory anyway: "I do the job; I get paid. Go run your little world." ))

we know what the rules are for rationality — J

Does the Freudian get to claim that his path is rational, that we are wrong about knowing the rules? — J

In short, the Freudian may be right, but what he can't do is justify a claim to being right, without engaging in more philosophy — J

So this was indeed the key word in the original post:

And what is your justification for asserting that such an explanation is true? — J

and this word is the private property of philosophy.

I keep having the feeling what you really had in mind was just epistemology. You mentioned somewhere an ascent biology → science → philosophy, which makes sense in terms of more and more general or abstract questions about knowledge. And thus justification of claims to knowledge. And justifying ― or being able to, or accepting the requirement to ― your claims to knowledge taken as a cornerstone of rationality.

I was hoping this thread was not about epistemology, so help me out here.

Arthur Koestler's definition of philosophy: "the systematic abuse of a terminology specially invented for that purpose." — Fooloso4

That's even better than my old favorite:

One might almost say that over-generalization is the occupational hazard of philosophy, if it were not the occupation. — Austin

@J

One more quick note, but then I'm occupied for the next few hours.

There is one quite well-known form of resisting being pulled into philosophy.

"How do you know that's a tree?"
"I speak English."

I believe Wittgenstein said there is nothing lacking in this answer, even though it is not at all the kind of answer that was hoped for. We might even say that the necessity of philosophy is one of the claims that he resisted ("one should be able to stop doing philosophy"), or at least a certain kind of philosophy.

Bonus note on questions that the questioner claims must be answered: this was Dummett's lesson to philosophers in the early seventies, that there was a pattern to a number of debates in philosophy, where one side was actually an anti-realist with respect to a particular class or issue. If you don't notice this, you keep getting boxed in by the realist, who insists that you agree or disagree with some claim, that there is or isn't some such-and-such, that you must have sat in the chair voluntarily or involuntarily (to use Austin's lovely example), and so on. But if your position is that there is no fact of the matter here, your being boxed in is an illusion, only philosophers kept trying to finesse their way out of questions whose legitimacy they should have straight up denied.

Anyway, there's some prior art on questions that carry with them a claim that you have to answer them, and answer only in the terms provided. Within philosophy, fighting over that is practically all philosophers do. For your thesis ― hey, at least it's philosophy!

if chemistry had this ability, it would be able to respond to a physicist's attempt at reduction using only the arguments available to it qua chemistry — J

Makes sense. Reduction here would be an example of a strategy that one discourse might use to assert dominance over another.

Two quick points about reduction, then, one for my side and one for yours:

(1) If the physicist says he can explain anything the chemist can using only physics, the best response of the chemist is "Go ahead." It can't actually be done, and the idea that it can be done is a myth.

(2) A better approach for the physicist: listen to the explanation of the chemist of how something works, and at some point ask why something that doesn't happen doesn't happen. At some point ― we're assuming ― the chemist will have to drop down a little, say from how some complex protein works to how the building blocks of this protein work, carbon phosphate whatevers. Keep doing this. Eventually, the chemist himself will have to reach for physics, because while reduction is a myth, and the laws of physics are not enough to do biochemistry, biochemistry is constrained by physics and you can eventually reach a level where the explanation for what happens and what doesn't comes not from chemistry but from physics.

This, we believe, is true across the natural sciences. You cannot, even in principle, use only physics to describe the ecosystem of the Serengeti, but that description nevertheless must be consistent with our understanding of physics. Or, if you like, you could interpose many other sciences in between, consistent with biology, which is constrained by biochemistry, and so on eventually down to physics.

And there is no natural science which constrains physics.

But there is mathematics and logic.

And what constrains them?

(Will respond separately to the other post after I've eaten something.)

Look, if you think the Jews had no moral rights under the Nazis then it follows that the Nazis did nothing wrong in exterminating them. I can't argue with someone who thinks that way. — Clearbury

Actually the Holocaust may not be the best example for your case.

SIEGEL: You write in "Black Earth" - and I'm quoting now - Jews who were German citizens were more likely to survive than Jews who were citizens of states that the Germans destroyed.

SNYDER: Yeah. Our image is of a progressive destruction of Jews inside Germany. But in fact, Germany, like most states that weren't destroyed, was a relatively safer place for Jews than the places where German power actually destroyed other regimes. Once we see this basic contrast that Jews in stateless zones had about a 1-in-20 chance of surviving whereas Jews in states had about a 1-in-2 chance of surviving, we have to ask the question about the causes of the Holocaust a little differently.

SIEGEL: And Hitler's attitude toward Poland or toward Lithuania, Latvia, Ukraine was quite different from his view of France or the Netherlands or Denmark.

SNYDER: That's an extremely important point. It turns out that in order to carry out something like a final solution, you have to first destroy state institutions. So the order is very important. When Germany invades Poland in 1939, it does so with the intention of wiping out not just the Polish state but the Polish political elite, that is, physically exterminate the people who could support a state. — NPR interview with Timothy Snyder

The Holocaust is actually a pretty complicated event.

That's what I thought you might be doing.

Does this have to be an argument, if I can put it this way, that philosophical maximalism is equivalent to philosophical minimalism?

Does it also function as an argument that no boundary between philosophy and the sciences (and possibly other empirical disciplines, and possibly the arts, ...) is definable much less enforceable?

I can put it differently. It's common around here to say that every time you open your mouth, you're doing philosophy. Every field of study is built on philosophical assumptions, blah blah blah. ― What if we said instead (or 'also', but I'd rather not) every time you try to do philosophy you end up talking about history and psychology and biology and ... That there is no point pretending you are insulated from the rest of human thinking just by calling what you're doing philosophy.

(My go-to example for this sort of thing used to be phenomenalism, which kinda presents itself as a supremely abstract from-first-principles take on perception, but is 100% dependent on knowing that the surface of the eye is 2-dimensional.)

Suppose some surly neo-Freudian interrupts me at the point where I assert that “there’s nowhere else to go.” Nonsense, he says. “I’ll give you a psychological-slash-reductive explanation of why philosophers do what they do, and this explanation will have nothing to do with ‛ideas’ or ‛reasoning,’ and everything to do with culturally determined modes of expression mixed with individual depth psychology.” Ah, but I can reply, “Indeed? And what is your justification for asserting that such an explanation is true?” We see where this has to go: We’re back to doing philosophy. My surly interlocutor has been trumped. — J

This isn't remotely convincing.

He hasn't been trumped. He'll stroke his inevitable beard and say, "Interesting. Do you often demand that people provide justification for what they say to you?"

Your guy wasn't even trying. Mine is holding his own even as a ridiculous stereotype.

the desire to find something better, more interesting, than what I called "an argumentative gotcha!" Maybe it can't be found, but that's not yet clear. I repeat that, if that's all there is, it's not much of a result. — J

Right. I didn't think I was introducing the idea, but endorsing your uncertainty.

How would chemistry, for instance, defend itself strictly within the discourse of chemistry from the challenge that it is really a form of physics? — J

But this seems like a whole different thing.

Were you ever suggesting that there might be a reduction of natural science to philosophy? If you were, I missed it.

My understanding of the thread was that philosophy does something different from science. What it does different might turn out to be not so interesting ― and we have some idea in what sense it might not be interesting, if it's just a cheap "gotcha" ― or it might be interesting, only it's hard to characterize what it might be doing that's interesting.

My suggestion was that any discipline could just keep doing its thing, even when confronted with philosophical questions. I think you were underestimating the determination of non-philosophers. Your psycho-analyst folds pretty quickly. I can absolutely imagine an historian, or a sociologist, or a neuroscientist just continually folding back into his own domain, with its own frameworks of explanation, whatever question philosophy wants to pose. Or an economist. Or a Marxist economist.

I guess we could debate that, but even if most disciplines choose to stay within their lane ― and so only use the handy hammer on the prescribed nails ― when challenged to justify themselves and their procedures, isn't it the most natural thing in the world to reach for that hammer and treat the philosophical challenge as de facto within their purview? Like, philosophy is begging to be a nail.

I'm not sure what kind of debate we would have without evidence to hand, except making up stories, but for me it barely needs defense.

To you, on the other, it's perfectly intuitive that philosophy is uniquely universal in this way. I find that puzzling. I mean, I know it's part of philosophy's self-image, but if you've been around a bit you must know that you have no hope of out-flanking Marxism by questioning it, or economics, or psychology, or neuroscience, or biology, or ...

But now you're talking about reduction, which I didn't think was on the table, and which surely we don't want to get into here.

Oh for Gödel's sake. — J

I cannot adequately express my appreciation for this response.

go with Gauss — Srap Tasmaner

Hmmm. Is this how Catholic mathematicians say "See you later"?

Gauss, who termed mathematics as that — jgill

Oh you're right! Well, never mind then. I'll go with Gauss.

war — Bob Ross

P.S.

Forgot to ask, why we should spend blood and treasure liberating members of the out-group. How is that putting in-group needs first?

The in-group is more important than the out-group. Each group has to protect its own viability first and foremost. — Bob Ross

I don't claim to understand your "moral realism," so maybe you can help me out here.

You have suggested we have duty to liberate the citizens of North Korea. Is that purely because we believe we have the status of moral agents, and a duty to carry out acts we deem moral? Or is it because North Koreans also have the status of being moral agents, and that's why we have a duty to them?

The answer to those questions would clarify for me whether we are supposed to consider North Koreans members of the in-group or the out-group. If they are moral agents toward whom we might have a duty, that sounds like we ought to consider them in-group. But if they are out-group, why would we have any duty to liberate them? ― I'll leave you to decide whether you want to defend the idea that they are out-group relative to "us" ― the West or whatever ― and not moral agents at all.

When you've decided you don't understand the question, I'll happily rephrase it.

philosophers have no business offering opinions within a scientific discourse — J

Dope.

Their super-power, if any, lies in their ability to defend themselves from challenges that would redirect their discourse into other disciplines. — J

I'm with you ― I believe ― in thinking this doesn't sound all that impressive.

(1) Who bothers to challenge philosophy?

(2) Are you sure that no other discipline has this "super-power"? I suspect every discipline does, even in good faith. (If all you've got is a hammer, ...)

(3) Are you sure this is anything more than a dirty rhetorical trick? Another "heads I win, tails you lose" sort of thing? ― Distinguished from (2) because you don't even need a discipline, just the willingness to treat discussion as competition.

*

I'm not bringing up science just as boosterism, but because I was thinking that the tradition of the "top-level" idea casts philosophy as specifically "the queen of the sciences" ― not as something set over against science, as it is so often seen these days. Even (on shaky ground here) something like Aristotle's "first philosophy" would embrace physics, biology, psychology, ethics, and politics as the rest, right?

Anyway ― I would distinguish between a view of philosophy as (either) the highest (or the most fundamental) science, and a view that philosophy holds some particular and special place precisely by not being science.

Why is it the case that philosophical discourse can question, and reflect upon, the discourse of physics, but the reverse is not the case? — J

Because philosophical discourse is more presumptuous?

Scientific journals are peer-reviewed. That's not a guarantee that they publish only truth, of course. It's just a first nibble by the rest of the scientific community, because it is ultimately this community which will take up, build upon, pass by, propose alternative theories, replicate or fail to replicate experimental results, and so on. A paper is never the end, just a contribution.

But are philosophers supposed to be some sort of super-peers? Should journals hold off publication until they've "checked with a philosopher"?

Are you claiming that knowledge does not exist outside mathematics? I don't see why "the elements being less well-defined" results in any serious problem here. — Leontiskos

While I think it's defensible to say that "knowledge does not exist outside mathematics," I don't think I have to, to show the difficulty.

Mathematical knowledge, to borrow Williamson's term, is "luminous": that is, when you know that P, you know that you know that P. That may put it too strongly: there are cases where you think you have a proof, but you don't; there are cases where someone has provided a proof, but it's complex enough that it takes a while for people to confirm that it is a proof. Nevertheless, there is an alignment of the process of knowledge production and knowledge justification, and a single standard governs both.

Outside of mathematics, there are no standards of either that garner universal approval, much less guarantee that production and justification are measured by the same standard. We may have knowledge, but in general we cannot know when we do and when we don't, and thus we cannot know when our valid arguments are sound and when they are not.

I'll throw in a side issue that emphasizes the difference. It is a wise saying that experiments which are not performed have no results. And yet, in mathematics your hypotheses can be so sharply defined that they do: a difficult theorem like Fermat's last theorem might be solved piecemeal ― you prove that if lemma X were the case, then you could prove theorem T, and then you look for ways to prove X. That is, in mathematics, it's not that unusual to prove a conditional, without knowing whether the antecedent is in fact true. I think the independence results in set theory are also different from the sort of thing we can ever hope to achieve in empirical investigations.

I'm not in love with this story. It would be nice to retreat instead to some sort of common sense that of course we know things and deduce more things in everyday life. Sure. But part of that common sense is also that there are exceptions, we turn out not to know what we think we do, we turn out not to be justified in making the inferences we do. So I end up back in the same place, because we already have a name for this sort of rule that generally works but has exceptions: that's probability. ― Philosophical attempts to close the gap and specify, in some vaguely scientific way, exactly the criteria for knowledge and inference, so that we can be on ground just as solid outside of mathematics, have not only universally failed, but there are reasons to think they must fail.

I do not see a way around making some kind of distinction here. Either only mathematics (and logic) gets knowledge and deduction ― and everything else gets rational belief and probability ― or there are two kinds of knowledge, and two kinds of deduction. Pick your poison.

Mathematical knowledge and empirical knowledge differ so greatly they barely deserve the same name. Obviously the history of philosophy includes almost every conceivable way of either affirming or denying that claim.

— Leontiskos

Given the explanation, can we deduce that Billy is not at work? — Leontiskos

Deduction should allow you to pass, by valid inference, from what you know to what you did not know. Yes?

In mathematics, these elements are well-defined. What do we know? What has been proven. How do we generate new knowledge? By formal proof.

Neither of these elements are so well-defined outside mathematics (and formal logic, of course). There is no criterion for what counts as knowledge, and probably cannot be. And that defect cannot be made up by cleverness in how we make inferences.

I see no reason to question the traditional view. "Our reasonings concerning matters of fact are merely probable," as the man said. There is deduction in math and logic; everyone else has to make do with induction, abduction, probability.

I hope you're enjoying your visit to Earth, but you should really check with your parents before interacting with the natives.

What do you dream of, Bob? Do you dream of peace and plenty? Or do you dream of making people listen to you?

I've always loved this one:

The Send-Off
By Wilfred Owen

Down the close, darkening lanes they sang their way
To the siding-shed,
And lined the train with faces grimly gay.

Their breasts were stuck all white with wreath and spray
As men's are, dead.

Dull porters watched them, and a casual tramp
Stood staring hard,
Sorry to miss them from the upland camp.
Then, unmoved, signals nodded, and a lamp
Winked to the guard.

So secretly, like wrongs hushed-up, they went.
They were not ours:
We never heard to which front these were sent.

Nor there if they yet mock what women meant
Who gave them flowers.

Shall they return to beatings of great bells
In wild trainloads?
A few, a few, too few for drums and yells,
May creep back, silent, to still village wells
Up half-known roads.


――――
"like wrongs hushed-up" ― oh, he could write.

Bob, Bob, Bob. Your position is such a jumble.

Maybe you thought to yourself, why don't we do more to oppose tyranny throughout the world? Why do we allow people to be oppressed by their own governments?

-- But, interrupted skeptical Bob, on what grounds would we oppose tyranny?

Democracy! Our values!

But then you realized this is trouble: a core democratic value is tolerance.

Which is fine, you thought, except people take it too far, allow themselves to be paralyzed by a mamby-pamby cultural relativism.

We've become like people who *say* they have religion, but don't want to convert anyone.

Well do we believe in democracy or don't we? If we do, let's act like it! Let's go convert some mofos.

-- Just because we believe? asks skeptical Bob.

Hell yeah! We believe, and if we really believe that's enough.

And if others believe something else, let them try too. Every country should act on whatever it believes, because ..., because ...

Because we can't give in ...

to relativism.

Two questions.

1. How do you impose democracy upon a people by force?

2. Should all nations think this way? Should all of them declare war upon all the others to impose their values upon other nations by force?

let the negation of C(P) be N(P) — TonesInDeepFreeze

Yeah that's an interesting idea!

I guess we could assume that nothing in N(P) would follow from anything in C(P), because follow-from would already have that sort of "transitive" property that we're used to.

I've tried to work out some consequences of this, but it's still not clear to me. (I had a whole lot of ideas that just didn't work.) It's interesting though.

Much of classical math existed before the introduction of set theory. — jgill

Yeah, I get that. Looking at the reconstruction of math using set theory is one way to hunt for the difference between math and logic, that's all. Maybe not the most interesting way.

We have that. — TonesInDeepFreeze

We already have: — TonesInDeepFreeze

We define consistency from provability. — TonesInDeepFreeze

Sorry. Obviously I haven't managed to make clear what I'm trying to do here, probably because I've been writing a bunch of stuff I ended up scrapping, so I probably think I've said things I haven't.

I'm trying to figure out how we could bootstrap logic or reasoning, informal at first, of course, what we would need to do that, what the minimum is we could start with that could grow into informal reasoning. I'm not proposing an alternative to the logic we have now. So

Why is that lacking? — TonesInDeepFreeze

is not the kind of question I was addressing at all.

For example, my last post suggested a way you might leverage a primitive understanding of consequence or "follows from" to piece together negation. I don't know if that's plausible, but it hadn't occurred to me before, so that's at least a new idea.

How do you know there is only one thing? — TonesInDeepFreeze

At first probably not! But you can see how a bunch of ideas that all point to "not sunny" might eventually get you there.

And as I noted, there's some reason to think other great apes already have the ability to reason about pairs of near opposites, even without an abstract concept of negation. I was imagining a way some sense of consequence might get you from such pairs to genuine negation.

Like I said, all very speculative, and probably not worth your time.

I don't know what you mean by "minimal inconsistency guard". — TonesInDeepFreeze

Roughly that the LNC could enforce a narrow, specialized sense of consistency ― that P and ~P are inconsistent, for any P ― and this would be enough to bootstrap a more general version of inconsistency that relies on consequence, so that with a fuller system you can say A and B are inconsistent if A → C and B → ~C. It's a bootstrapping technique; start with special cases and leverage those to get the general. Special cases are easier, cheaper, in this case don't require additional resources like consequence.

It's probably all too speculative to do much with. Most of the ideas I've had in the last few minutes just recreate the fact that you can build the usual collection of logical constants with negation and one of the others (unless you want to start with the Sheffer stroke). If I were to say, maybe we need both consistency and consequence as core ideas ― that's almost all that would amount to.

I was thinking, though, that there might be a way to get negation out of a primitive sense of consequence ― not the material conditional, just an intuition of what follows from what ― something like this: any given idea (claim, thought, etc.) has a twin that is the one thing guaranteed under no circumstances to follow from it, and that would be its negation. You could define ~P roughly by partitioning the possible consequents into what can and can't follow from P, but the two buckets are different: what can follow from P might initially be empty, who knows; but what can't never starts empty.

If, like the gorillas, you didn't already have the abstract concept of negation, the bucket we're going to use to define negation would probably be full of stuff ― given any P, that bucket will have stuff that ~P follows from, in addition to ~P itself, maybe, sometimes. Example: if P is "It's sunny", our bucket of things that don't follow includes "It's cloudy", "It's nighttime", "It's raining" ― all different things that "It's not sunny" follows from.

Don't spend any time trying to make sense of all this. It's just me thinking on the forum again.