- #36
Hurkyl
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More detail please. In this thread, we have used the word "set" in at least three different senses:jordi said:False. Proof: let (blank) := set
"X is a set" is meaningful. "X belongs to the set of all sets" is not meaningful, because the set of all sets does not exist.
(1) A set in some model of ZFC
(2) A set in some model of ZFC
(3) A synonym for "logical predicate"
Furthermore, the corresponding logical predicate would be
(blank) is a predicate
which, incidentally, is also meaningless.(Unless, of course, you meant it as a metalogical predicate, or as a predicate about strings -- but then that wouldn't have anything to do with the "logic = set theory" correspondence)
And, for the record, there are forms of set theory that do have a set of all sets.