|Copula: a copula is a connection of the subject with a predicate within a sentence or statement. E.g. the sky is blue. The copula is not the same as the "is" of identity.|
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Copula/Geach: if you understand concept and object correctly, you do not need copula. - Instead, you can use "falls under". - (In ancient times it was also handled like this) - ((s) "is a" suggests false identity (at most partial identity, i.e. classification) - Frege late: VsFrege early: nor "falls under" - "is a"/Frege: does not mean "belongs to a class"!
"Is a..."/Geach: is no logical relation between an x and an object (class) called "human."
Logic Matters Oxford 1972