[Raak] Not quite sure how to interpret the question. The Answer obviously consists of [the] words [on the card] but the words making up The Answer don't refer to something that consists of words (e.g. "a phrase") How'd I do?
[!John] A condition? NO
[Tuj] I'm so vain, you bet I think this clue is about me? NO (I've already been an answer in this game, in fact).

(I figure I'm allowed a serious question as well.)

[CdM] PP the Painter? NO
[CdM] Music? NO.
[FGZstar] Can be tanged? NO

[Phil] Religious? NO
[Tuj] A human invention? I WOULD SAY NOT, altho there are arguments either way.
[GL] Persistence? NO :)

[CdM] Numbery? BARELY
[Tuj] alloneword? There are three words on the card, but there's definitely a one word answer I'd accept.

So, so far, we have tenuous connections to both the arts and mathematics.

[INJ] Greeks knew? I EXPECT SO, altho I know of no evidence they did.

(Having googled the topic of The Ancient Greeks and The Answer, and discovered it to be an extremely subtle matter, I'd put it another way: The Answer was certainly manifest in Ancient Greece and its existence was unlikely to have been overlooked, but for reasons that will become clear, a straight yes would be a significant oversimplification.)