Did you bother even reading the rest of what was said? — Michael
Q(a)→∃x(x=a)
Q(a) already assumes that a exists, so of course it follows - from the definition of ∃x. — Banno
And can you remind my why we started on this argument? — Banno
Good idea. A bit of depth.
We can perhaps see the difference most clearly if we look to the use of each rather than meaning. Let's look at an example in which it might make sense to separate truth from belief.
There's a tree over the road. Suppose Fred believes the tree is an English Oak. But it is a Cork Oak.
We might write, in order to show the bivalency of the belief:
Believes ( Fred, The tree over the road is an English Oak)
And
True (The tree over the road is a Cork Oak). — Banno
I think the best way to define the "mention operator" as I called it, and had yet to be able to answer your question, is to say what it does is it converts a natural-language string into a name for that said string using the same alphanumeric characters, but changing its function from a proposition to a name. — Moliere
One thing I'm noticing here, in your examples, is you like to treat existence like a predicate. So the existence of things gives propositions used their truth-value. — Moliere
"This river contains many fish" is true iff there exists a river, and the river contains, and the object contained by the river are fish, and the relationship of said fish to the numerical predicates in the context its within is such that speakers would say "many". — Moliere
You agree with this:
So non-existent rivers are not facts? I might agree with you there.
— Luke
On your account of correspondence, how is it that "There is no river on this dusty plane" true? The fact is the dusty plane, rather than the no-river. — Moliere
Or, the classic "The present king of France is bald". There is nothing to which this proposition refers as we speak it today. So you'd likely say something like the proposition is either obviously false, given there is no fact to the matter, or does not have a truth-value, or something like that. — Moliere
But that's something I liked about the plums example -- here was something that would matter, and is a lot more natural to our way of thinking. When you open up the fridge and see nothing in it, the no-plums have an effect on your state, at least. The nothing has an effect on us. And especially the no-plums, if we wanted plums. The no-plums have a relationship to the believed proposition. The fact is the empty fridge, and yet the sentence is "There aren't any plums in the ice box", and it's true. — Moliere
So what are you doing here? — Banno
What's the difference between seeing the sheet and seeing the sheet-as-sheet? — creativesoul
Sheet-as-sheet is stronger :strong: — magritte
Where does mention or use come into it? — Luke
If deflationism is no more than endorsing a sentence that one believes to be true, then there is no place for correspondence, verification, "finding out" whether or not a proposition is true, truthmakers, or facts. There is nothing more to truth than endorsement and, therefore, no way of determining or discovering the truth of a given proposition. According to deflationism, looking for plums in the freezer has nothing to do with the truth or falsity of the proposition about plums in the freezer. There is then nothing "outside" the proposition that counts for or against the truth of a given proposition. A T- sentence is then no more than an abstract equation with absolutely no relation or reference to reality, as several here have noted already. — Luke
According to the correspondence theory, the truth of a proposition is determined by whether or not a proposition corresponds to the empirical facts of the world. On the other hand, the deflationary claim made by Pie and @Banno(?) is that true propositions are identical with the empirical facts of the world. Opposing this deflationary claim, I argued that language and the empirical facts of the world are distinct. — Luke
It is difficult to try and draw this distinction without attempting to use language to gesture at the existence or instantiation of things in the world other than language. — Luke
What's the difference between seeing the sheet and seeing the sheet-as-sheet?
— creativesoul
I was going to say no difference — Moliere
Sheet-as-sheet to me indicates naming and descriptive practices accompanying the seeing. This eliminates language less seeing of the sheet, which - of course - is a problem. — creativesoul
So, I believe that what seems self-evident in logic is so because of what we perceive and what we can imagine perceiving, and what we can consequently imagine being the case. To my way of thinking this is the essence of modal logic; what is impossible in all worlds just is what we find impossible to imagine, and I think what we can imagine is constrained by the general characteristics we are able to identify in what we perceive. If we perceived very different images of the world with very different characteristics, then we would be able to imagine what for us, as we are, is unimaginable, and our logics would be correspondingly different
According to the correspondence theory, the truth of a proposition is determined by whether or not a proposition corresponds to the empirical facts of the world. On the other hand, the deflationary claim made by Pie and Banno(?) is that true propositions are identical with the empirical facts of the world. Opposing this deflationary claim, I argued that language and the empirical facts of the world are distinct.
— Luke
I don't think I'd say that true propositions are identical to the *empirical* facts. I'd say that true propositions and facts are one and the same, but that doesn't mean I'd discount reality. Reality just isn't the totality of facts, in that case -- as you note, they're just true propositions, so I certainly wouldn't want to reduce the entirety of reality to them. I don't think either @Banno or @Pie have said they'd do the same, either. — Moliere
According to the correspondence theory, the truth of a proposition is determined by whether or not a proposition corresponds to the empirical facts of the world. — Luke
The problem with using the imagination as a basis for logic is that people have different capacities for imagining -- so a logic, then, would only be understandable insofar that we have the imaginative capacity. If our imaginations are a bit dim, then our logic will also be a bit dim, and if our imaginations are incredibly active, then our logic will be incredibly active. — Moliere
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