This is an assumption. You can invite people to share your assumptions, but you can't really bang them over the head with them. Assumptions have no weight. — frank

It's also true.

If it were false then it's negation would be true, irrespective of our certainty and judgements and justifications. Which would be a contradiction.

If it were false then it's negation would be true, irrespective of our certainty and judgements and justifications. Which would be a contradiction. — Michael

Antirealism is about the world, not metaphysics.

Read through the whole discussion. It is the same discussion as this one. Every (philosophical) discussion on TPF becomes the same discussion, if it has enough time to get there. It’s kinda depressing, to be honest.

Every (philosophical) discussion on TPF becomes the same discussion, if it has enough time to get there. It’s kinda depressing, to be honest. — Srap Tasmaner

That's not depressing, it's brilliant. You've discovered the attractor of philosophical discourse.

You've discovered the attractor of philosophical discourse. — Isaac

It's been done before, many, many times. (And whether I discovered it or invented it is exactly the debate.)

I suspect it's really selection bias. Out of the entire population that might post here, the vast majority keep on walking, a small number are interested in academic philosophy, a tiny number of those become academic philosophers, an unknown number create an account here, a fraction of those read some of the site, and a fraction of those post. Certain interests, and certain sorts of arguments, seem to be over-represented in those who post, relative even to the population of those with an interest in academic philosophy.

Yes. It is comfy though. The best thing to happen is for a thread to burn bright and die early, before the assumptions underlying the assumptions get doubted, and fundamental points of reference of our discussants don't come into conflict. I think we often get to the same thing, whereas academic discourse maybe doesn't, because we get the luxury of doubting arbitrary assumptions while remaining in the same discourse.

Also yes to selection bias.

Back when I was a tournament chess player, it seemed to me that the style of play of serious players -- that is, who studied, practiced, and played a lot, regardless of talent -- was a generation or so behind what the world's top players were doing. This shows up in opening repertoire too: things current GMs aren't playing are still common in weekend tournaments among amateurs. Some of that is really a matter of knowledge and technique: GMs might avoid an opening as black because the current state-of-the-art for white forces a very favorable endgame. That's not the kind of advantage amateurs can reliably convert, and so it's not the kind of advantage they think about much or know much about.

I think something similar happens with us. We advocate positions professionals consider to have nearly fatal flaws because we don't know that -- don't even know what counts as that sort of flaw -- and because the people we talk to don't know it either, don't know that there is such a case to be made or how to make it. Thus even when a discussion here lands right on such a point -- about as close to dispositive as philosophy gets -- no one knows this is enough to call the bout and move on.

Philosophy and chess are similar in this sense, that they are driven by fashion, but fashion that is shaped by an arms race. Obviously not an infallible procedure for approaching truth, but also one that is easily misunderstood. Grandmasters will abandon a line in an opening because of one specific move (initiating a variation) available to their opponent. The technical details matter, and they are what drive the shifts in fashion. New ideas in old openings have surprise value (the Theoretical Novelty), but it also has to be a good idea. Sometimes a great player will refute a TN over the board, in real time.

So I see professional philosophers in part as engaged in rather technical issues because it's how you push alternatives toward the possibility of decision. Absent such technical knowledge and expertise, our choices of fashion are somewhat arbitrary, and there are never any decisive encounters of one view with another.

We advocate positions professionals consider to have nearly fatal flaws because we don't know that — Srap Tasmaner

You are right, of course. But there are takeaways that make the discussion not entirely useless. I came across a novel approach to the logic of truth - revision theory; although the material is difficult and I was unable to garner much interest from anyone else. I also enjoyed the rare agreement with @Pie early in the thread and with @Isaac later on, including some surprise that Isaac found the discussion of "counts as" useful. There's something of the neurological basis for language hiding in there.

The discussion with you was intriguing for a while, although disappointingly it petered out without issue. @Michael drew attention to a few issues with T-sentences that are well worth keeping in mind.

Other views, summarised here, were predictable.

The last few banal, meandering pages are down to folk trying to take an absurd view seriously. They are not a typical of the thread.

revision theory — Banno

Think I was otherwise occupied when you mentioned that. I'll take a look.

Your example only applies to a hypothetical world, in which it actually is raining. What good is it, if it doesn't apply to the real world? — Metaphysician Undercover

The hypothetical shows the logical consequences that follow when it is actually raining in the real world.

In other words, in the real world, it is possible that Alice could have real knowledge, — Metaphysician Undercover

:up:

but it is also possible that it is not knowledge. — Metaphysician Undercover

Also :up:. In which case she mistakenly thinks that it's raining when it isn't.

So we cannot correctly judge Alice as having knowledge because we cannot know the answer to this. Alice may have knowledge, or she may not. — Metaphysician Undercover

We can know the answer to this by doing just what Alice did, namely, by looking and seeing that it's raining outside.

Andrew M Srap Tasmaner: we had a discussion about that Rovelli paper a few years ago here. — fdrake

:up:

You've discovered the attractor of philosophical discourse.
— Isaac

It's been done before, many, many times. (And whether I discovered it or invented it is exactly the debate.) — Srap Tasmaner

As is the option that they are false alternatives, thus giving rise to the strange attractor. I'm reminded of the Greg Egan short story "Unstable Orbits in the Space Of Lies". Maybe that's the philosopher's fate...

The hypothetical shows the logical consequences that follow when it is actually raining in the real world. — Andrew M

It does not actually show the logical consequences which follow when it is actually raining in the real world, and the problem is that your assertions that it does, and attempts show that it does, are nothing less than deception. The hypothetical shows the logical consequences which follow from the assumption that it is actually raining in the real world. And, there is a very big difference in meaning between "it is actually raining in the real world", and "I assume it is actually raining in the real world". The latter recognizes the possibility that it is not raining in the real world.

Your argument seems to be that if we cannot be certain that it is raining then it is not actually raining and that if we cannot be certain that it isn't raining then it is not actually not raining. This doesn't follow and is even a contradiction. — Michael

No, I'm not saying anything like that. What is at issue here is the nature of possibility, and particularly the possibility that it is not raining, when it appears like Alice knows that it is raining. This is because Andrew claims that if people appear to have knowledge, then it turns out later that what they knew at the time (or thought they knew) was incorrect, we ought to retroactively say that what they had at that time was not knowledge. This means that unless we are absolutely certain, we ought not call something "knowledge", because it could turn out not to be knowledge. This assumption forces upon epistemologists the necessity of considering fallibility (the possibility of incorrectness), when discussing what qualifies as "knowledge". Do you not agree that as epistemologists, if there is a possibility that the thing which appears to be knowledge is not actually knowledge, then we ought not call it "knowledge"?

So my argument is that if it has to be actually raining out for us to correctly call what Alice has "knowledge", (as Andrew asserts), then we ought not label what Alice has as "knowledge" unless we are certain that it is raining out.

although the material is difficult and I was unable to garner much interest from anyone else. — Banno

It looked to me like it fell to the same problem as any other theory of truth, but with more interesting results. The "interesting results" were definitely beyond me, so no noise from me. But that you landed on "false" just meant it had the same problem as any theory of truth, as I understand the liars.

This means that unless we are absolutely certain, we ought not call something "knowledge", because it could turn out not to be knowledge. — Metaphysician Undercover

Why? I don't need to be certain that something is true to assert that it is true. I will have Weetabix for breakfast tomorrow. I'm not certain that I will, but I'm still going to say that I will.

We don't require certainty to assert things. If that were true then we ought stay silent on everything except anything that is necessarily true. It would make for a very quiet, impractical world.

Do you not agree that as epistemologists, if there is a possibility that the thing which appears to be knowledge is not actually knowledge, then we ought not call it "knowledge"? — Metaphysician Undercover

No. I'm happy with fallibilist knowledge. It's consistent with ordinary use. The list of things we claim to know is greater than the list of things we claim to be certain about, and so clearly what we mean by "know" isn't what we mean by "certain".

So my argument is that if it has to be actually raining out for us to correctly call what Alice has "knowledge", (as Andrew asserts), then we ought not label what Alice has as "knowledge" unless we are certain that it is raining out. — Metaphysician Undercover

And this doesn't follow.

You start by saying that it has to actually be raining for Alice to know that it is raining. You then conclude by saying that we have to be certain that it is raining for Alice to know that it is raining. So as I said in my previous post, you are asserting that if we are not certain that it is raining then it is not actually raining. What evidence or reasoning is there for this? Most of us accept that sometimes we are not certain but it is actually raining.

The hypothetical shows the logical consequences which follow from the assumption that it is actually raining in the real world. And, there is a very big difference in meaning between "it is actually raining in the real world", and "I assume it is actually raining in the real world". The latter recognizes the possibility that it is not raining in the real world. — Metaphysician Undercover

Not necessarily. From the fact that it‘s raining, you can’t conclude that it might not be; for all you know, it might necessarily be raining.

I don’t think any of that affects how a hypothetical works. It can be quite natural to construct a hypothetical with an assumption that is at least counterfactual, for explanatory purposes: if this thingy weren’t here, this other thingy would blah-blah-blah; if squirrels couldn’t climb trees so quickly, then cats would catch them easily.

You can even do this with an assumption that is necessarily false, and that’s roughly how proof by reductio ad absurdum works. Must it be the case that a space with properties A, B, and C has property D? Assume A, B, C, and ~D and then derive a clear contradiction. That means the entire set of premises, taken as the conjunction A & B & C & ~D, is necessarily false.

But in all these examples, the important thing about a hypothetical is that you must discharge your assumption. So the conclusion of a hypothetical is always, at least implicitly, a conditional. “Suppose I have a dollar bill and 2 quarters. Then I have $1.50 total,” is to be understood as “If I have a dollar bill and 2 quarters, then I have $1.50.”

That’s the whole point of hypotheticals, to see what follows from the assumption, to see whether something in particular does, not to make a claim about whether the assumption holds or not, or even whether it’s possible or not. Sometimes in informal reasoning, people miss the step of discharging their assumptions, so they’ll end up claiming something like “But I just proved that I have $1.50!!!“ when all they‘ve proven is that if they had $1.50 then they’d have $1.50.

Since I’ve cited Margaret Wise Brown, I’ll cite another of my favorite works of philosophy, Open House for Butterflies:

If you’re pretending you’re a lion, it’s good to know if you’re pretending you’re really a lion. — Ruth Kraus

nothing less than deception — Metaphysician Undercover

I for one would appreciate it if you stopped saying things like this. Andrew and Michael are clearly not trying to deceive you. If they are mistaken, then they are mistaken, but there’s no deception here.

This means that unless we are absolutely certain, we ought not call something "knowledge", because it could turn out not to be knowledge. — Metaphysician Undercover

To me, certainty sounds like a psychological state, something like “maximal confidence,” and it’s irrelevant. It could turn out I was wrong even if I was certain. Would you like here to do the same thing you don’t like with the word “knowledge” and say that if that were to happen, then it must be that you weren’t really certain, but only thought you were?

if there is a possibility that the thing which appears to be knowledge is not actually knowledge, then we ought not call it "knowledge"? — Metaphysician Undercover

Knowledge is just actual knowledge, and knowledge of the actual. It doesn’t have to be necessary, and neither does the proposition known. What is cannot not be, but in many cases it might not have been. There are different sorts of necessity at work here. We can say that it is possible for something that is not to have been without denying that it is. “I know that it’s raining but maybe it isn’t” is incoherent; “I know that it’s raining but it might not have been” isn’t.

The rewrite rules make this really clear. If you have a propositional attitude Φ toward a proposition P, Φ is factive just in case you can, with no change in truth-value, rewrite “S Φs P” as “P and S Φs that.”

I know that it is raining = It’s raining and I know that
Steve thinks that it is raining ≠ It’s raining and Steve thinks that

The interesting thing people keep saying is that it might “turn out” that P isn’t or wasn’t the case, that I was right or wrong. No worries when we’re just dealing with belief, because that suggests that there is newly acquired evidence. No one bats an eye at “I thought she was at the store but it turns out she wasn’t.” For all I knew, she was at the store, but now I know more and my knowledge now includes that she wasn’t.

No one seems to bring up, “I thought she was at the store and it turns out I was right.” Here the speaker is still not claiming to have known she was at the store, but to have had the belief, a belief which was true, without his knowing that.

But “I knew that water freezes at 32°C but it turns out it doesn’t” is incoherent. Why? Because knowledge is factive, so something is entailed about the state of the world by what you know; water either freezes at 32°C or it doesn’t. If you know that water doesn’t freeze above 0°C, then it’s not your knowledge that rules out the possibility of water freezing at 32°C, but what is entailed by your knowledge.

Finished A Nice Derangment of Epitaphs today. I think I get along with its conclusion rather well -- I really do suspect there is no such thing as a language, in these terms of rules and such, and especially when spoken of in the abstract (rather than, say, English). I suppose I'm not as disturbed by that notion as others might be. Maybe I'm just ignorant of its implications. It sounds like one would conclude that we are simply animals barking, that language is meaningless, and we're all just acting out of the drives we happened to be driven by due to our evolutionary heritage.

But that would run counter to things like understanding the meaning of a poem, wouldn't it? Perhaps the whole approach of specifying rules of interpretation is what's wrongheaded? We get by without explicit reference to rules quite frequently. It's just not some kind of universal rule or something.

I really do suspect there is no such thing as a language, in these terms of rules and such — Moliere

Which is a perfectly good prior. What do you do next?

Maybe I'm just ignorant of its implications. — Moliere

That would be one thing to do next. If the theory has entailments that are false, it's toast. But arguments for and against at this level of abstraction tend to be question-begging, so this is tricky. (I know I didn't find Derangement at all convincing, even though my sympathies then were different from what they are at the moment.)

Perhaps the whole approach of specifying rules of interpretation is what's wrongheaded? — Moliere

This would be the other thing to do next. Try specifying some rules and see how it goes.

If it can't be done, that ought to become pretty clear at some point. Linguistics is littered with failed theories, even failed research programs, like any other science, but not all of them.

Which is a perfectly good prior. What do you do next? — Srap Tasmaner

My first response was "No idea" :D -- but that's no fun:

To get back at truth, it seems to me that if there's no ur-Language, or at least rules for all languages which count as Language in general, then we'd have to put aside any semantic theory of truth (if we hoped that theory was universal, at least). There'd be nothing of truth as much as we're talking about the English predicate "...is true", which does have a history and all, but clearly we'd be picking out the "good cases" in that history and so we rely upon -- even if indistinct -- some notion of truth that is bigger than the English predicate "...is true"

But then you say here:

Linguistics is littered with failed theories, even failed research programs, like any other science, but not all of them. — Srap Tasmaner

And I have a great respect for the sciences (as well as philosophy, for that matter).

So I'll lay out my suspicions --

It seems to me that in order to generalize about language you'd have to have a representative sample. But no one person knows enough languages to even come close to that (think about how many languages have already perished up to now, and how the kinds of societies which don't prioritize capital and conquest might have very different dialects than us), so you kind of just have to assume that the languages you do know are at least related to this general picture of language -- that real language use instantiates the general features of language, and it does so so strongly that the specifics of any one language don't obscure it.

And when it comes to even the small number of languages I'm familiar with I'm having a hard time picking out much similarity when it comes to meaning such that we'd have a rule which translates the meaning of one language to another. Really you just have to know both languages in order to perform a translation. Knowledge of a particular language is about as "deep" as knowledge of language goes -- and translation is an art of understanding two languages, rather than a rule.

But that's all just based on my mere experience with language learning and such. I have a hard time conceptualizing what Language, in general, could possibly mean other than "whatever it is we mean when meaning with means" -- so my suspicions are likely just based on my small impression of things, and there's much more to the story that I'm unaware of.

Proof is in the pudding. There are lots of linguists doing lots of fieldwork. Maybe they'll find something, maybe they won't. Arguments that they must, or that they cannot, hang in the air exactly the way a brick doesn't.

I don't think it would be the end of linguistics if there were no universal grammar but several kinds of language, but we all came from the same place and probably had language before we left, so it's a reasonable expectation that there is some unique capacity for language (since evolution *usually* but not always solves problems once).

more substantial theories of truth [...] “7 + 5 = 12” is true iff “7 + 5 = 12” follows from the axioms of maths — Michael

Is that a proposed formulation somewhere?

It doesn't work in ordinary mathematics. A sentence is either true or false but not both. And a sentence is true if and only if its negation is false. But with our ordinary mathematical axiomatizations, there are sentences such that neither the sentence nor its negation are derivable.

Proof is in the pudding. There are lots of linguists doing lots of fieldwork. Maybe they'll find something, maybe they won't. Arguments that they must, or that they cannot, hang in the air exactly the way a brick doesn't. — Srap Tasmaner

Yeah, that makes sense to me. I certainly don't want to be read as saying either that they cannot or must -- if anything I've been pushing against notions like that. I certainly don't expect the meandering thoughts I have to in some way impinge on a project people have dedicated their lives to. I'm sure these thoughts have been thought by people better educated on the matter than I :D

I guess, for us -- .or really, for me, since I think you're still pretty much on board with correspondence theory -- I have to think on your question and get at another approach that does utilize something that I'm more confident in.

(EDIT: "Homebase" for me is Kant, but I'm also confident that he's wrong :D -- so who knows)

Is that a proposed formulation somewhere?

It doesn't work in ordinary mathematics. A sentence is either true or false but not both. And a sentence is true if and only if its negation is false. But with our ordinary mathematical axiomatizations, there are sentences such that neither the sentence nor its negation are derivable. — TonesInDeepFreeze

Is 7 + 5 = 12 derivable?

Of course it is.

But in any "adequate" system, there are statements such that neither the statement nor its negation is derivable. So derivability doesn't work for defining 'is true'.

But in any "adequate" system, there are statements such that neither the statement nor its negation is derivable. So derivability doesn't work for defining 'is true'. — TonesInDeepFreeze

I wasn't defining "is true", only stating that "7 + 5 = 12" being derivable is the necessary and sufficient condition for "7 + 5 = 12" to be true.

'7+5=12' is true iff '7+5' is a theorem

is the case because both sides of the biconditional are true.

But that is not an instance of a substantial theory of truth.

I think you need to look at the context of that reply. It stems from this post:

We've been taking as a starting point "snow is white" is true iff p and then discussing p, whereas I think we should instead take as a starting point snow is white iff q and then discuss q.

Snow is white iff snow appears white, or
Snow is white iff snow reflects all wavelengths of light, or
Snow is white iff snow has a mind-independent sui generis property of whiteness, etc.

We can then bring this back to truth-predication by understanding that if "p" is true iff p and if p iff q then "p" is true iff q.

"Snow is white" is true iff snow appears white, or
"Snow is white" is true iff snow reflects all wavelengths of light, or
"Snow is white" is true iff snow has a mind-independent sui generis property of whiteness, etc. — Michael

When I say something like "snow is white" is true iff snow reflects all wavelengths of light I'm not also implying that "it is raining" is true iff snow reflects all wavelengths of light. I'm simply trying to provide more substance to the truth of "snow is white" than what the trivial T-schema offers.

The example of "7 + 5 = 12" was just a hypothetical, like the three examples of "snow is white" above. I'm not committing to any one of them as a matter of fact.

Without claiming that you do or don't commit to the example as being of a substantive theory (though literally you did say that, it's reasonable to take you now as clarifying that you didn't mean it literally), I asked, "Is that a proposed formulation somewhere?" and went on to say why it doesn't work.