'I am my world — Wayfarer

Whatever it might have been, it is not "The world is me".

He stepped beyond the solipsism that traps you.

You're just basically repeating what I said in slightly different words. — Janus

Then I haven't been able to follow what you are saying.

Fine, Waif.

"Everything exists within experience" is wrong. It's only experience that sits within experience. The world is not limited by you.

how could it not be right to say that the prebiotic Universe was not dependent on mind? — Janus

This sort of question is risible. The Orion Nebula is not dependent on you, nor are trilobites. But your saying anything (thinking, believing, doubting...) about them is dependent on you.

Yawn.

Neither of those is quite right. It's a silly argument. We do talk about how things are. Sometimes what we say is true. Sometimes not.

But you know that this is mostly crap. Realism/idealism is a false opposition.

Propositions are bits of language, so they are human... "mind-dependent" in the casual sense thrown around here. Constructed, if you like.

What is the case will often be the case regardless of what you or I believe, yet how we talk about what is the case is a construct made up by us.

That is, not everything that can be believed is true. Truth and belief are different.

SO the supposition that it's all either mind-independent or it isn't, that's simplistic shite.

It's not that things always conform to thoughts, nor vice versa.

Which is why I keep rabbiting on about direction of fit.

But that's not what has been said. What has been said is that if a proposition is true then it is justifiable. — Michael

Yes. And if B then A→B, for any A or B. So if we take justification as being the consequent of a material implication then that any truth is justified is trivial.

But is that what you mean?

(do I need to add that if it is justified, then it is by that very fact justifiable?)

But that's not what has been said. What has been said is that if a proposition is true then it is justifiable. — Michael

And again, if that is no more than that it can be made the consequent of a material implication, that is trivially right. So again, what is it to be "justified"?

I don't see that you can substitute □(p → ◊Kp) for ∀p(p → ◊Kp). I've tried doing that with the argument at SEP 2. The Paradox of Knowability, but...

Substituting p∧¬Kp in to □(p → ◊Kp) gives □((p∧¬Kp) → ◊K(p∧¬Kp))

and so ◊K(p∧¬Kp) stands. Something is amiss, since Fitch's paradox still stands.

(edited).

Just to be clear, my target here is the idea that a proposition can only be true if justified. That suggests truth is a two=place predicate over propositions, which it isn't.

Part of this is to point out that the notion of unjustifiable remains unclear. What is the justification for the truth of "I have a pain in my toe"? Or is it not truth-apt?

Every unjustifiable truth is unjustified but not every unjustified truth is unjustifiable. — Michael

Yep, something doesn't seem to grasp.


And by "justification" we mean...?

The antecedent of a material implication? - too Strong, since anything can be justified that way.

So, what?

So you don't think unjustifiable truths are unjustified? How odd.

Or is that just pedantry in the service of your confusion?

You are playing silly buggers until you fill in what it means for something to be justified. But given that you cannot get your head around material implication, and validity, what you have to say will not be all that useful.

:wink:

The problem with realism is that it entails this kind of global skepticism. If there are unknowable truths then there are unjustifiable truths, and if there are unjustifiable truths then a proposition not being justified is not a good reason to reject it. — Michael

Interesting that you think this a problem. That there are "unjustified" truths is pretty obvious. Of course, now we have to look towards what it is to be "justified", but I gave some examples earlier.

That Leon disagrees is affirming.

So you think you need antirealism to avoid being a vatted brain. Right.

Antirealism doesn't claim, and nor do antirealists acknowledge that it entails, that all truths are known. — Michael

Sure. And they do this by rejecting classical logic.

The second thing is that it is consistent with a deflationary account of truth. — Michael

Yep.

The third thing is that it avoids certain absurdities that realism allows for, e.g. that it is possible that we are unknowably brains in a vat. — Michael

Realism does not commit to vat brains. This is an odd objection.

The fourth thing, albeit directed at Janus, is that it is not obviously wrong. — Michael

Sure.

Is any of this inconsistent with what I have said?

See you after the umlaut.

You tell me. We are talking about realism and antirealism. You brought in constructivism. Set it up for us, if you like.

Is this the second Warble, or the third? The gonad is in your corner.

I'm not defending it. Someone else can give an account, if they want.

Constructivism Lite. Clayton's constructivism - the constructivism you have when you are not a constructivist.

Sure, why not.

And Farnarkling. It's what we do here. My example is better.

:grin: Then we have a more explicit impasse.

You seem to me to be always verging on saying something interesting, which is what keeps me in the conversation... but it seldom seems to reach the point.

What is it about antirealism that you have to say?

For my part, I have I hope been at least clear that I think the difference is one of choosing between language games rather than finding the true and proper way to do ontology.

Have you understood that?

If Goldbach’s conjecture is provable then even if it hasn’t yet been proven it is true. — Michael

That's... rather the point at issue...

...“we are brains in a vat”... — Michael

:roll: Let's not.

The above sentence is true because the sentence fragment on the left hand side (“‘P’ is true”) means the same thing as the sentence fragment on the right hand side (“P”). — Michael

Nuh. It can just be extensionally equivalent. Tarski and Davidson and so on. Meaning needn't feature.

You appear to be trying to conflate deflationism and disquotationalism. — Michael

I used disquotation as an example for deflationary method. That's not hard.

I think a better example is... — Michael

You don't get the humour, then. Not a surprise.

(Edit: nor the point, actually, which was about constructivism, in this case in satire rather than in mathematics - something your "better" example misses)

It seems to me that you ignore most of what I've writ, preferring to nit pick a few near-irrelevancies.

Yawn.

How long is each warble in Farnarkling?

A warble lasts exactly as long as John Clark says it lasts. "A warble lasts 23 minutes" is neither true nor false, until Clark decides...

But now, not.

Another case where antirealism might be of more use than realism.

I’m confused. Are you a truth deflationist or not? A truth deflationist will accept that (1) and (2) mean the same thing. But now you say that they don’t mean the same thing and are only “truth-functionally” equivalent. That strikes me as being decidedly non-deflationary. — Michael

One way to give a deflationary account of truth is to say that "P" is true IFF P. Hence for any statements of the sort ("P" is true) we can write P, removing "...is true". Nothing here about meaning. Deflation of truth doesn't equate to deflation of meaning.

As the SEP article says, “Fitch’s proof is not a refutation of anti-realism, but rather a reason for the anti-realist to accept intuitionistic logic. — Michael

Yep. And as I have said, the difference is a choice between ways of talking about stuff. I'm not arguing that antirealism is always wrong.

I just don’t understand why you think that antirealism about mathematics doesn’t entail that all mathematical truths are known/attitudes but that antirealism about the weather entails that all truths about the weather are known/attitudes. — Michael

The choice is between saying that there are unknown mathematical truths and saying that there are unknown physical truths. I'd entertain Kripke's approach to truth for maths but not for physics. So we can usefully say that Goldbach's conjecture so far has no truth value but that there is water on Miranda is either true or it is false.

Is that so hard?

The claim isn’t that all truths are known. The claim is that all truths are knowable. Remember, anti-realists reject Fitch’s conclusion. — Michael

Yeah, they can reject it all they like. It doesn't follow that they are right. ∀p(p→◊Kp)⊢∀p(p→Kp

The claim isn’t that all truths are attitudes. The claim is that all truths are knowable. — Michael

...and knowledge is a propositional attitude, a relation between someone and a proposition. Same fish. SO if all truths are knowable, all truths are attitudes. Do you hold that truths are attitudes?

Remember, you claim to be a mathematical antirealist. Presumably you accept that mathematical truths aren’t attitudes and that there are unknown mathematical truths. So simply extend your understanding of propositions about numbers to propositions about medium sized dry goods. — Michael

I hope I made it very clear that realism and antirealism are different ways of talking, and that

...one can be a realist in one area and an anti-realist in another. — Banno

If you think this is wrong, tell me why.

Sentences (1) and (2) mean the same thing. — Michael

Well, no. That's far too vague. One is about the weather, the other is about a sentence. But (1) and (2) are arguably truth- functionally equivalent.

Dummett then argues that (2) is only meaningful if it is verifiable. This is his Language Acquisition Argument. — Michael

Ok, so are you agreeing with Dummett? I gave examples above of truths that are apparently not verifiable, and my conclusion is that verification is insufficient for a complete theory of truth. I waved at Tarski and deflation as alternatives. Next?

If (1) is only meaningful if it is verifiable then unknowable truths make no sense. — Michael

And if verification is a poor theory of meaning and of truth, this is of no consequence.

Frankly, there was a lot in the post I made above that remains unaddressed, yet far more pertinent to the issue than the direction you are taking.

https://thephilosophyforum.com/discussion/comment/947737

Sentences (1) and (2) mean the same thing. — Michael

...I would say no more than: “It is raining” is true≡ it is raining. Nothing here about meaning. I think you introduced "meaning" into the discussion - perhaps not - but either way, it remains unclear how this helps the topic, or relates to it any more than bringing in intension.

I'm not sure what it is you are arguing for, if indeed you have a thesis that is being touted. Or what it is you are objecting to, if you are making an objection.

It’s not clear what you mean by “means” here. — Michael

And you think it was clear for you? I was only copying your use:

"'it is raining' is true" means "it is raining" — Michael

We have a choice between dropping meaning and looking to use and dropping meaning and turning to truth. I like it both ways. But not dropping meaning and looking towards verification, as you suggest, and frot he reasons I gave. Nothing to do with "entails". Or entrails.

You appear to be mixing up your use and mention. — Michael

Not I. You appeared to do so, with

"'it is raining' is true" means "it is raining — Michael

...hence my reply. Again, "'it is raining' is true" means it is raining, NOT "'it is raining' is true" means "it is raining". See the mention where there should be a use in the second?

A simple account would be to first argue that "'it is raining' is true" means "it is raining", and then to argue that "it is raining" is meaningful only if it describes a verifiable event. It would then seem to follow that "'it is raining' is true but unverifiable" makes no sense. — Michael

But "'it is raining' is true" means that it is raining, not "it is raining".

That looks trivial, but it isn't. A name does not have a truth value. "It is raining" is the name of a proposition.

Why should we hold that "it is raining" is meaningful only if it describes a verifiable event? Why go there when we can say "it is raining" is meaningful iff '"It is raining" is true' can have a truth value?

Correspondence works wonderfully for observations of medium-sized smalls goods, and for that purpose it is a pretty good approximation to truth. But if what we want is a definition of truth that will work in all cases, it's wanting. There are truths for which it is not obvious that there is some verifiable event that makes them true. What verifiable event might you elicit to claim that arithmetic is true? Or that it is true that you enjoy ice cream? Of that 100 cents makes $1? Or even "PV=nRT", which presumably might only be verified by collecting every such instance.

Correspondence is not wrong, just insufficient.

I understand you to be offering these as examples, rather than some position you wish to defend? But substantive theories of truth I take it to have been shown to all be inadequate in various ways. Hence Tarski's work and the subsequent deflationary accounts.

My comments about truth being a single-placed predicate are intended to show that there are uses for assigning truth to sentences outside of our attitudes towards them. I've highlighted these elsewhere -

Surprise
We are sometimes surprised by things that are unexpected. How is this possible if all that is true is already known to be true?

Agreement
Overwhelmingly, you and I agree as to what is true. How is that explainable if all there is to being true is attitudes? How to explain why we share the same attitude?

Error
We sometimes are wrong about how things are. How can this be possible if all that there is to a statement's being true is our attitude towards it?

Now I know we have previously agreed that Kripke's theory is interesting here, so we might cut to that, and ask if it is antirealist.

Knowledge, belief, and so on are relations between us and propositions. They are two-placed predicates.

Truth is not relational. It is a single-placed predicate.

One way to think of antirealism is as looking for ways to treat truth as a relation.

That's not germane here. You can see my opinion in other threads.

Not at all. It's based on sentiment. — Wayfarer

Yep. Scientism as a faith.

Wow. What a post.

...but it does not have the same meaning qua modus ponens (or modus tollens) — Leontiskos

What does that mean?

https://www.umsu.de/trees/#(((A~5B)~1A)~5B)~4(((~3A~2B)~1A)~5B)

Cheers. The wider point is that formal logic removes ambiguities in natural languages, which is what I take you have been saying.

My mistake. Not "If A then not A" means "not A or not A" but "If P then Q" means "not P or Q".

"If P then Q" means "not P or Q" presumes an inclusive OR.

"If A then not A" means "not A or not A". — Michael

"If P then Q" means "not P or Q". — Michael

Only if "or" is used inclusively. The ordinary language use is often exclusive, or ambiguous.

So this doesn't help.




...except perhaps to provide an example of how formal logic works out the ambiguities of natural language. Which is part of what it is for.

You entirely missed the point. Sure, science tells us how things are. It does not tell us how they ought be.

Even if "Science explains how things are and how events have unfolded over the past 4.6 billion years; these are facts" we cannot conclude from that alone how things ought to be.

This is a gap in your argument.

We can easily envision two possible scenarios: one in which humans align their decisions with evolutionary trends, leading to peaceful, balanced, and harmonious development; and another where these trends are opposed, resulting in death, freedom only for those in power, economic and social inequality, slavery, widespread pollution, erasure of beauty, etc. — Seeker25

That comment shows a very deep misapprehension of evolution.

If you don't think those arguments valid, then you haven't understood "validity". But we already knew that from your OP. And since you do not understand validity, there is no point in presenting you with valid arguments, in order to prove anything.

You have placed yourself outside of rational discourse.

Cheers.