One of the (dumb) arguments against acceptance of transgender people takes disagreement about the definition of “man” and “woman” as dangerous to a functioning society. Setting aside that this argument depends first upon confusion about the difference between gender and biological sex, the idea that we need to agree one this particular ontological fact is very odd when the people making the argument don’t say the same about other ontological (and metaphysical) disagreements.
@arossp Well put. For uneducated people (or even highly educated but not in matters of philosophy), this is probably one of the only places where they face the jarring observation that words and concepts are more fluid than they think. I'm very influenced by Wittgenstein on this. You can play this game with any word. For example, is a cisgender man who has had his genitals surgically removed still a man? Is a man's brain in a vat still a man?
@arossp I would venture to say further (my own speculation) that humans did not create languages with rigid necessary and sufficient conditions in mind. Rather, we invented languages and words that were specific enough to "get the job done" to disambiguate two or more things in someone else's head. Then, when we go back and try to apply rigid logic to these words, we understandably find all sorts of inconsistencies.