That's the very definition of a property in first-order logic. First order logic is extensional by design.
So you using a non-standard interpretation? — Banno
SO for any proposition P you have:
P is true IFF it is consistent and identical with itself
Consistent with what? "Lightwave wrote this post" is consistent, but not true - I wrote this post. — Banno
If you think that properties are collections then reality consists only of collections, which are concrete things, because properties as abstract things that have instances don't exist. — litewave
The nominalist cancels out the property and treats the predicate as bearing a one-many relation directly to the several things it applies to or denotes. — Goodman, p49
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