[coldtea]

>Just don't have conversations where two different people have different implicit definitions of sameness, and each sees the other's position as clearly stupid, because the other person is using an unstated, but different, definition of "same"

As you say, discussing X while having 2 different ideas of X is obviously wrong -- people practically talking past each other.

But that's only if the discussion is not philosophical but just a practical, everyday conversation.

That's because in the latter people talk and talk about X while X goes unexamined, where the essense of a philosophical conversation is to examine X, and investigation how each one defines it, and what might be correct or wrong about any singular definition.

A non-philosophical discussion would be: - X song is the same as Y, they stole it. - No it's not, they just have the same chord changes. - They should come out with their own, they're copycats.

Whereas a philosophical disussion would be in the vein of: "what is sameness?" (itself), "when we can say that a song is stolen from another?" etc.