My point is that we have words because they call out a useful, albeit fuzzy, blob of conceptspace. We may try to claim that two words mean the same thing, but if there are different words, there's probably a reason -- because we want to reference different concepts ("connotations") in someone's mind.

It's important to distinguish between the concepts we are trying to reference, vs. some objective equivalence we think exists in the territory. The territory actually includes minds that think different thoughts on hearing "unmarried" vs. "bachelor".

ETA: My point regarding Kant was this: He should have seen statements like "All bachelors are unmarried" as evidence regarding how humans decide to use words, not as evidence for the existence of certain categories in reality's most fundamental ontology.