There's no such thing as a fallacious biconditional. — The Great Whatever

By that I mean a proposed biconditional which is actually false, e.g. it is raining iff I am a man.

Your reply doesn't make sense to me.

Which part? My claim that the following are not equivalent:

1. the Earth exists in this situation iff "the Earth exists" is true in this situation
2. the Earth exists in this situation iff "the Earth exists in this situation" is true

Or the part where I asked you to clarify how I am to respond to you? Consider this again:

1. The cup is red
2. The above is true

According to you, there's a difference between asserting that the cup is red and asserting that "the cup is red" is true. So if you assert 1 and if I agree with you, do I have to assert 1 or do I have to assert 2? Does it make sense for me to assert 1 but to deny 2? It seems quite obvious to me that to assert 1 but to deny 2 is a contradiction.

If you assert that the cup is red and if I accept that your assertion is true then ipso facto I accept that the cup is red, and if I accept that the cup is red then ipso facto I accept that your assertion is true.

The property only obtains as a judgment. — Terrapin Station

So facts don't matter? If I judge a factually incorrect statement as true, then it's true? And even if it's a fact that P, "P" wouldn't be true if no one judged it to be?

I think that that's obviously a problem.

The world exists separately from us, this is its facticity. What happens in the world happens regardless of our presence. Sure we can learn about it, study fossils, the cosmos, learn how the world works, but since we are also part of the world, our viewpoint has to be circular. — Cavacava

The world doesn't exist separately from us, it just exists independently of us. We live in the world, and it is all around us. We are part of it, as you say. But we can't be both separate from it and part of it.

Much of what happens in the world does indeed happen regardless of our presence, and it would continue to do so without our presence. That's why idealism is wrong.

Not sure what you mean when you say that our viewpoint must be circular.

But "the world" is a construct... — Metaphysician Undercover

Sure, "the world" is a construct, but the world isn't. The world is not "the world". The world is the world.

...and the idea that what happens in the world happens regardless of our presence is a construct as well. — Metaphysician Undercover

Well, of course the idea is a construct.

Is it that time again? Irrelevant idealist truism time?

So it's really not useful to take this type of realist position because it lacks in what we would call "truth". — Metaphysician Undercover

Perhaps, but that doesn't follow from what you just said, so try again.

And once you dismiss this position as ill-founded, something which is commonly believed but not true, you no longer will see yourself as part of the world, but the world as part of yourself. — Metaphysician Undercover

But you are part of the world, regardless of how you see yourself. That's so inward-looking, ignorant, and oblivious. I might see myself as a pony, but that doesn't mean that I am one.

The true territory is not external. — Metaphysician Undercover

If you say so... :-d

Much of what happens in the world does indeed happen regardless of our presence, and it would continue to do so without our presence. That's why idealism is wrong. — Sapientia

Just to split hairs, but objective idealism allows for things to happen regardless of our presence.

Just to split hairs, but objective idealism allows for things to happen regardless of our presence. — Michael

Can you remind me what that is, and how it allows that? I get the objective part. Is "objective idealism" the most appropriate term for such a position? In the context of this discussion, idealism posits the mind-dependence of truth (although, admittedly, I did stray from that definition), so idealism can't allow for things to be independent of the presence of mind if that would entail corresponding truths which are likewise independent. But it need not entail that, I suppose.

Can you remind me what that is, and how it allows that? Is "objective idealism" the most appropriate term for such a position? In the context of this discussion, idealism posits the mind-dependence of truth, so idealism can't allow for things to be independent of the presence of mind if that would entail corresponding truths which are likewise independent. But it need not entail that, I suppose. — Sapientia

The world itself is one big mental thing (à la pantheism or even panpsychism, I guess), so even though things are dependent on the presence of mind, they're not dependent on the presence of human minds (or the minds of any other intelligent life).

The world itself is one big mental thing (à la panpsychism or pantheism, I guess), so even though things are dependent on the presence of mind, they're not dependent on the presence of human minds (or the minds any other intelligent life). — Michael

Oh! I thought you had a bigger point to make. I have no problem talking about minds in general rather than human minds. I just adopted the language of my interlocutor.

I thought you had a bigger point to make. — Sapientia

No, like I said, just splitting hairs.

And yeah, maybe "objective idealism" isn't the best name for that position, but I can't think of a better one right now. "Non-intelligent-life-dependent idealism" is a bit of a mouthful.

And yeah, maybe "objective idealism" isn't the best name for that position — Sapientia

Maybe not, but it's the name it has. ;)

Maybe not, but it's the name it has. ;) — Michael

But I don't like that name, so I'm renaming it "Dave".

If I judge a factually incorrect statement as true, then it's true? — Sapientia

"That statement is factually incorrect" is a judgment that someone makes (if they're using correspondence theory that is) about the relationship of the proposition in question to facts. It doesn't obtain that a statement is factually correct or incorrect in lieu of the judgment. One person might judge that P is true (where they're using correspondence theory and they're judging that P is factually correct) while another person judges that P is false (where they're using correspondence theory and they're judging that P is factually incorrect). And actually, all that it functionally refers to to judge that P is true or false under correspondence theory is that P is factually correct or incorrect.

So this answers your second question, too. Propositions are not true or false in lieu of a judgment about whether they're true or false. One major reason for this is that meaning doesn't obtain in lieu of someone explicitly thinking about specific things semantically, so propositions do not even exist in lieu of someone thinking about them (this last part follows from the conventional analysis of what propositions are--namely, that they're the meaning of particular sentential expressions; they're not identical to the sentential expressions per se--"snow is white" is not identical, as a sentential expression, to "schnee ist weiss," since one is in English and contains the word "snow" where the other doesn't, while the other is in German and contains the word "schnee" where the other doesn't, but they are identical as a proposition (although on my account, that's only in case an individual assigns the same meaning to both)).

Sure, "the world" is a construct, but the world isn't. The world is not "the world". The world is the world. — Sapientia

Let me phrase that another way then. You can use "the world" all you want, but I do not know what this refers to, other than something imaginary, in your mind, like a unicorn. You can say the unicorn is not "the unicorn" all you want, but that doesn't resolve anything.

But you are part of the world, regardless of how you see yourself. — Sapientia

OK, so that tells me a little bit, the world is something I'm part of, whether I like it or not. I suppose it will punish me if I don't pay attention to it? That would appear like it is separate from me. What makes you think that I am part of it? Why would it hurt me, if I am part of it, then it would be hurting itself? Does "the world" refer to the same thing as "God"?

If you say so... :-d — Sapientia

And what you say is somehow better than what I say?

Well, of course the idea is a construct.

Is it that time again? Irrelevant idealist truism time? — Sapientia

OK, I see you at least understand what I'm saying. You're doing better at understanding what I am saying than I am doing at understanding what you are saying. Now tell me where I can find this thing called the world. I want to see if it's really there, to see if you know what you're talking about.

But whether a certain sentence expresses a proposition, and so whether a certain sentence is true, is probably mind-dependent, in the sense that whether something counts as a sentence, and what a sentence expresses, is dependent on a linguistic practices in turn dependent on minds in some way. — The Great Whatever

In some way...

Sure, in some way, but are they dependent in the relevant way? If there were never any minds, then there would never have been any linguistic practices. That is one way in which the latter is dependent on the former, the latter can only arise as a consequence of the former. But that isn't the issue.

There were minds, and linguistic practices have since arisen. It is now about whether the one depends on the other, going forward.

What do you mean by "linguistic practices"? Because if you mean something like a set of rules, then I don't think that that does depend on any mind in the relevant way. It depended on a mind or minds, but now that the rules have been set, they don't depend on any mind.

Yet, it's possible you might mean something other than that, or something more than that. There don't actually have to be minds applying these rules in practice. They've already been set and applied, and that is sufficient.

To deny this would be to say that for any arrangement of things in the world that logically or conceivably could be interpreted, according to some imaginary linguistic system, in a certain way, in fact already is — The Great Whatever

In a certain way...

I'm not yet sure whether or not I've denied what you meant, because I'm not yet sure what you meant. But if I have, then no, I don't think so. Interpreting always requires an interpreter and the act of interpretation. If that hasn't happened, then it hasn't already been interpreted.

In the case of the author who no longer exists, along with all other minds, he did in fact mean something with those symbols. This implies that there was some sort of rule that was set up, such that these symbols mean this and not that. If that counts as an interpretation, then they had one. Why would this rule or interpretation no longer apply? It has already been applied. Why would that somehow be reversed just because the author, along with all other minds, ceased to exist?

...and so you'd be forced to say that basically everything is a sentence, and everything expresses every conceivable proposition, always (since there will always be a logically conceivable linguistic convention that could be so arranged). — The Great Whatever

I am not forced to do any such thing.

...whether a sentence is true is mind-dependent, because what it means is mind-dependent, even though the truth it expresses isn't. — The Great Whatever

What a sentence means is not mind-dependent. And whether it is true is also not mind-dependent. So, whence mind-dependence?

What a sentence means is not mind-dependent. — Sapientia

But what about that it has meaning? Can a string of symbols written on a page have meaning even when it isn't being read? Although we might argue that physical things like ink and paper continue to exist even when we're not around, can we say the same about meaning? Is meaning a physical thing? Is it a particular arrangement of atoms? If not then what is its ontology? Something neither physical nor mental?

"It's a terrible thing to lose your mind, or not have a mind." -- Dan Quayle

By that I mean a proposed biconditional which is actually false, e.g. it is raining iff I am a man. — Michael

This biconditional is not 'false' simpliciter if interpreted materially; it is true or false depending on the situation applied to. Applied to the situation I'm in right now, it's false because I'm a man, but it's not raining (where I am) [although even this is complicated by using 'I,' which technically since you used it refers to you and not me, but we can ignore that]. But if I were not a man, or if it were raining, it would be true. A material biconditional only says that in a certain situation, the truth values of the statements flanking the iff match.

What you need is something stronger, a strict biconditional, i.e. by your iff you must mean some sort of universal quantification over situations, such that for each situation, the truth values of the statements flanking the iff match in that situation.

Which part? My claim that the following are not equivalent:

1. the Earth exists in this situation iff "the Earth exists" is true in this situation
2. the Earth exists in this situation iff "the Earth exists in this situation" is true — Michael

I agree – that was my entire point. The point is that 1) is false, where 'this situation' refers to the situation I presented to you. This is therefore a counterexample situation to your strict biconditional, and therefore it's false. That 2) is true does not help you, because this is not what you need; you need 1).

According to you, there's a difference between asserting that the cup is red and asserting that "the cup is red" is true — Michael

Yes. One predicates something of a cup, the other predicates something of a sentence. In cases where the sentence "the cup is red" does not mean that the cup is red, but something else, their truth conditions clearly come apart.

So if you assert 1 and if I agree with you, do I have to assert 1 or do I have to assert 2? Does it make sense for me to assert 1 but to deny 2? — Michael

It would be inconsistent for you to assert 1) and deny 2), but what this shows is that the two statements are materially equivalent in the current situation, not that the strict biconditional holds, which is what you need.

So, given that "the cup is red" means that the cup is red in the current situation, the material biconditional "the cup is red iff 'the cup is red' is true" holds in this situation, since whatever 'the cup' refers to, the two statements flanking the iff must have the same truth value. But again, material equivalence is not what you're after, since if you go by material equivalence, a claim like "Donald Trump wins the 2016 U.S. election iff America exists" is also materially true by the same standards; but it is not true as a strict biconditional since the truth values of the two statements won't match in every conceivable situation.

The same holds for the red cup case, which the way you're presenting the example, by forcing yourself to ask whether they're both true or not in this situation, is obscuring. This is because the point is precisely that there are other situations in which their truth conditions will come apart, viz; those situations in which "the cup is red" does not mean that the cup is red, but something else. For instance, if "red" meant what "blue" does now, then in such a situation "the cup is red" would be true just in case the cup was blue, in that situation.

Part I

Why do you think that whether a proposition is true or false is a matter of judgement? — Sapientia

How can it be otherwise? — Wayfarer

Because it isn't impossible that one of the alternative theories is correct, and your theory is incorrect. It is possible that whether a proposition is true or false is a matter of correspondence, and judgement is merely what we do when we think that something is true or false.

You seem to be confusing judgement of the truth with truth itself, which is a category error. Do you also confuse sight with what is seen? The act of talking with what we talk about?

Propositions don't float around in the ether, they are not natural forms, but only exist in the minds of rational beings who are capable of making statements, which may be true or false. — Wayfarer

That's not true. A proposition is a meaningful statement, right? Well, we can produce meaningful statements. They depend on a mind for their production, not for their existence. This production is an act which makes the internal external. If it hasn't been stated, then it isn't a statement at all. And if a proposition is a meaningful statement, and statements are external, then propositions cannot be internal, and therefore cannot exist in the mind.

So, not only is it not the case that propositions only exist in the minds of rational beings who are capable of making statements. It cannot be the case that propositions exist in any mind.

If the mind making the statement meant something with the statement, then it has meaning, yes? You know that that makes sense. You normally think along those lines all the time.

Let's say an author wrote a book, as many have done. That book isn't meaningless. It is actually full of meaning. That is because the author meant something with the book. He didn't just close his eyes, think about something else, and randomly press buttons on the keyboard. He meant something. And that is its meaning. That it might mean something completely different or nothing at all to someone else doesn't matter, because it doesn't change that. It doesn't have to mean anything to anyone, because that wouldn't change that.

So, we can talk about it sensibly in this way, or we can say that there must be a mind there for it to mean something to - which might seem plausible at first, but can lead to implausible logical consequences.

So you and I will judge something to be true or false - apart from that, there is nothing inherently true or false in nature, is there? — Wayfarer

You tell me. How would you know that there is nothing true or false? You don't actually know that. Pointing to our judgement doesn't do anything. We both agree that we judge things to be true or false, but, for all you know, any of those judgements may well actually be correct.

'Things are neither good nor bad, but thinking makes it so', said the bard. — Wayfarer

Yes, so said the bard. He said many things. And meant certain things with the things that he said, regardless of what you or I or anyone thinks, and regardless of whether anyone thinks at all or even exists. You can't change the past.

But, anyway, we're talking about truth here, and that reasoning would lead to absurd logical consequences. The bard was a playwright, not a logician.

To be continued.

What a sentence means is not mind-dependent. — Sapientia

This is what I'm disputing. Sentence meaning depends on linguistic practice, which in turn, at least as far as we're familiar with it, depends on minds.

This is what I'm disputing. Sentence meaning depends on linguistic practice, which in turn, at least as far as we're familiar with it, depends on minds. — The Great Whatever

I said more than that one comment, and which addresses the above.

I didn't feel like addressing the rest.

That's fine, but then I don't get why you bothered to reply in the way that you did.

I already knew that.

To make clear the crucial point of disagreement.

You haven't made anything any clearer. What was clear remains clear, and what was unclear remains unclear.

I agree – that was my entire point. The point is that 1) is false, where 'this situation' refers to the situation I presented to you. This is therefore a counterexample situation to your strict biconditional, and therefore it's false. — The Great Whatever

But I haven't asserted 1. I've only asserted 2.

My claim is that the following assertions are equivalent:

1. It is true that the Earth existed in a situation where there were no linguistic practices
2. The above is true
3. "The Earth existed in a situation where there were no linguistic practices" is true

In cases where the sentence "the cup is red" does not mean that the cup is red, but something else, their truth conditions clearly come apart. — The Great Whatever

But that's not the case I'm considering. I'm considering the following:

The cup is red iff the first part of this sentence is true.

It is implicit in the T-schema that the meaning of the sentence mentioned on the left hand side is the same as the meaning of the sentence used on the right hand side. Which is why we can also say that "Schnee ist weiß" is true iff snow is white.

For instance, if "red" meant what "blue" does now, then in such a situation "the cup is red" would be true just in case the cup was blue, in that situation.

Yet it is still the case that for any assertion "it is true that p" there is an equivalent assertion "'q' is true". That's the point I'm making. It doesn't matter if the actual letters (or sounds) used in the sentence are the same or not.

My claim is that the following assertions are equivalent:

1. It is true that the Earth existed in a situation where there were no linguistic practices
2. The above is true
3. "The Earth existed in a situation where there were no linguistic practices" is true — Michael

OK, but this doesn't get you what you want. What you need for the biconditional to hold is:

In the situation in which there are no linguistic practices, materially "The Earth existed" is true iff the Earth existed. But as I've shown this isn't so, and this serves as a counterexample to the strict biconditional.

It is implicit in the T-schema that the meaning of the sentence mentioned on the left hand side is the same as the meaning of the sentence used on the right hand side. — Michael

No, it isn't.

Yet it is still the case that for any assertion "it is true that p" there is an equivalent assertion "'q' is true". That's the point I'm making. It doesn't matter if the actual letters (or sounds) used in the sentence are the same or not. — Michael

Then you should not phrase your claims in terms of the sort of biconditional you have been all along, nor make arguments based on this, if it is not what you mean.

Besides, what you say here is still false. It's not true that these assertions are (ever) equivalent, as I've already shown, since their truth conditions are different.

An assertion of "It is true that the cup is red" is not equivalent to an assertion of

" 'The cup is red' is true",

Since these two mean different things; one says a cup is a certain color, the other says a certain sentence is true. In the current situation, they are materially equivalent in virtue of what the sentence happens to mean, but counterfactually one might be true and the other false. So their truth conditions are distinct.

The world doesn't exist separately from us, it just exists independently of us. We live in the world, and it is all around us. We are part of it, as you say. But we can't be both separate from it and part of it.

Much of what happens in the world does indeed happen regardless of our presence, and it would continue to do so without our presence. That's why idealism is wrong.

Not sure what you mean when you say that our viewpoint must be circular.

Well your phrasing is better than mine, yes we live in the world. It must be circular because we have no immediately knowable criterion, no way of standing outside the world. The problem is that in order to know the world we must know ourselves, in order to know ourselves, we must know the world.....

No, it isn't. — The Great Whatever

It has been tacit in my application of the T-schema that the meanings are the same. Obviously I'm aware that the same syntax can be used to mean different things and that different syntaxes can be used to mean the same thing.

Then you should not phrase your claims in terms of the sort of biconditional you have been all along, nor make arguments based on this, if it is now what you mean.

It is what I said at the beginning:

The way I see it is that the sentence "it is true that p" is equivalent to the sentence "'p' is true" — Michael

And, again, it was tacit in this claim that the "p" used and the "p" mentioned mean the same thing (rather than have the same syntax) – which is why it's consistent with "it is true that I am a bachelor" being equivalent to "'I am an unmarried man' is true".

Besides, what you say here is still false. It's not true that these assertions are (ever) equivalent, as I've already shown, since their truth conditions are different.

The truth conditions of the following are the same:

1. It is true that the cup is red.
2. The above sentence is true.

Since these two mean different things; one says a cup is a certain color, the other says a certain sentence is true. In the current situation, they are materially equivalent in virtue of what the sentence happens to mean, but counterfactually one might be true and the other false. So their truth conditions are distinct.

When I say that the cup is red iff "the cup is red" is true I'm not saying that the cup is red iff any sentence which has exactly the string of symbols "the cup is red" is true, irrespective of what this sentence means. So to say that the T-schema fails because in some counterfactual situation the string of symbols "the cup is red" might mean that the cup is blue is a non sequitur.

You might as well say that 1 + 1 doesn't equal 2 because in some counterfactual situation I might be doing binary mathematics in which case 1 + 1 equals 10. The fact that I can use the same symbols in different ways is irrelevant. When I'm using them in this way, 1 + 1 equals 2, and the cup is red iff "the cup is red" is true.

The truth conditions of the following are the same:

1. It is true that the cup is red.
2. The above sentence is true. — Michael

No, they are not. For the truth conditions of two sentences to be the same, it must be that the proposition they express has the same truth value evaluated relative to all possible situations.

But this isn't so, since evaluated relative to situations in which "the cup is red" means the cup is blue, the proposition expressed by 1) can be true, while that expressed by 2) will be false.

So to say that the T-schema fails because in some counterfactual situation the string of symbols "the cup is red" might mean that the cup is blue is a non sequitur. — Michael

It is not a non sequitur in any way. The whole point of stating a strict biconditional is that it holds in counterfactual situations.

You might as well say that 1 + 1 doesn't equal 2 because in some counterfactual situation I might be doing binary mathematics in which case 1 + 1 equals 10. The fact that I can use the same symbols in different ways is irrelevant. When I'm using them in this way, 1 + 1 equals 2, and the cup is red iff "the cup is red" is true. — Michael

Not at all. 1 + 1 will still equal 2, even if say, you use the symbol '5' to refer to 1. In such a situation, the equation (read: 'sentence') '1 + 1 = 10' would be true, but nonetheless it would still be true that 1 + 1 = 2.

---

What you can say is that for any assertion "p" in a situation there is an assertion materially equivalent to it in that situation of " 'p' is true," but this is not what the biconditional you're stating means, and none of the heavy metaphysical theses you typically martial as a result of it follow from this.

No, they are not. For the truth conditions of two sentences to be the same, it must be that the proposition they express has the same truth value evaluated relative to all possible situations.

But this isn't so, since evaluated relative to situations in which "the cup is red" means the cup is blue, the proposition expressed by 1) can be true, while that expressed by 2) will be false. — The Great Whatever

In such a situation both 1) and 2) will be true (assuming that the cup is blue, of course; if it isn't then both will be false).

It is not a non sequitur in any way. The whole point of stating a strict biconditional is that it holds in counterfactual situations.

As I've said, the bi-conditional is to be understood as "the cup is red iff the first part of this sentence is true". You misrepresent the bi-conditional by changing the meaning of the sentence mentioned but not the meaning of the sentence used.

You might as well say that the following is false:

She kicked the bucket iff she kicked the bucket

Because, after all, in some counterfactual situation the first part of the sentence might mean that she died and the second part of the sentence might mean that she struck a bucket with her foot. It's a strawman interpretation of what is being said.

Not at all. 1 + 1 will still equal 2, even if say, you use the symbol '5' to refer to 1. In such a situation, the equation (read: 'sentence') '1 + 1 = 10' would be true, but nonetheless it would still be true that 1 + 1 = 2.

You miss the point. Both of the following are true:

1. 1 + 1 = 2
2. 1 + 1 = 10

The first is true using decimal numbers (among others) and the second is true using binary numbers. Your claim that the T-schema is false because in some counterfactual situation a sentence with that same syntax would be false is akin to saying that 1) fails because in some counterfactual situation (e.g. binary mathematics) an equation with that same syntax would be false (or, rather, nonsense).

What you can say is that for any assertion "p" in a situation there is an assertion materially equivalent to it in that situation of " 'p' is true," but this is not what the biconditional you're stating means, and none of the heavy metaphysical theses you typically martial as a result of it follow from this.

Again, all I said is that I understand the sentence "it is true that p" to be equivalent to the sentence "'p' is true" (where both ps mean the same thing rather than just have the same syntax). If this then entails a particular metaphysics, then so be it.