Of course, if a proposition is true, then it is true. That is just a tautology, and a necessary truth. But that does not imply that a true proposition cannot be false. It is true that Quito is the capital of Ecuador, but that does not mean that it is impossible that a different city in Ecuador is the capital (say Guyaquil). We have to distinguish between two different statements:

1. Necessarily, if p is true, then p is true. And,
2. If p is true, then p is necessarily true.

1. is, of course, as I wrote, a necessary truth and a tautology. But 2. is just false since it implies there are no contingent truths, and that is false. You have to watch where you place that term, "necessarily". since it never follows that because p is believed to be true that it is true.

The sentence "p is true to" (the individual, or the group) means no more then that the individual or the group believes that p is true. It leaves it open whether p is true or not. It doesn't matter to the truth of any proposition that anyone believes it is true. And, similarly, it does not matter to whether p is true or not whether p is accepted as true or not. "Accepted as true" is just a synonym for "believed true".

More reading here about modal fallacies like the one mentioned above. That one is called the modal fallacy since it is so common.

What about this?:[INDENT]Someone believes this sentence (/proposition).
[/INDENT]Is it not true just when someone believes it? Indeed. So "since it never follows that because p is believed to be true that it is true." is false but it is generally true. (And more than generally true, it is true for virtually all propositions except those similar to the above, if any.)

What sentence are you talking about?

I don't know what you mean.

Someone believes this sentence (/proposition).

I meant the very same sentence. Here is a clearer example:[INDENT]S. Someone believes the proposition expressed by (S) to be true.
[/INDENT]This is true only in case someone believes it to be true. That is impossible according to what you wrote:[INDENT][...] "it never follows that because p is believed to be true that it is true."[/INDENT]

But what is the proposition expressed by (S)? Is there such a proposition?

Presumably there is. Unless you want to ban self-reference or something like that. Is that how you get around liar paradoxes?

That is a way. There is a question as to what "this statement" refers to.

I think it is implausible. I've been reading up on dialetheism. Very exciting stuff. Not to be dismissed easily.

"this statement" (or "this proposition" refers to whatever proposition expressed by the very sentence. Do you think that is a problem? It does not seem so to me.

So, by substitution, "this proposition is false" means, ' "This proposition is false" is false'. And you claim to know what that means? Which is to ask, whether you claim to know what are its truth conditions?

What kind of substitution is that?

Substituting,"this sentence is false" for, "this sentence", of course. Isn't what "this sentence" is referring to?

I meant the very same sentence. Here is a clearer example:
[INDENT]S. Someone believes the proposition expressed by (S) to be true.
[/INDENT]This is true only in case someone believes it to be true. That is impossible according to what you wrote:
[INDENT][...] "it never follows that because p is believed to be true that it is true."
[/INDENT]

Alright. Yes, I claim to know what that means. Banning self-reference is not very straightforward. You would have to ban sentences such as this too:[INDENT]The proposition expressed by this sentence is true.
[/INDENT]Which is not paradoxical.

And the proponent of banning self-reference have explaining to do. Why are all self-referential sentences bad? It seems to me to be overkill and ad hoc.

I don't have any preferred solution, but dialetheism is very interesting.

I think that sentence has no subject. (I mean, "The proposition expressed by this sentence is true.").

I did not say that all self-reference is bad. I think we have to examine the particular case.

I am sure it is. So is Spinoza.

Alright. What makes the sentence above bad?

Presumably, the sentence expresses a proposition. You'd need to explain why it doesn't. It seems so much like other sentences that do express propositions.



Graham Priest is the most known defender of it. Maybe you should give his book a read. It's called In Contradiction.

I don't know about Spinoza. I don't read anything that old.