Two grammar questions

What is poetry? Who knows?

Not a rose, but the scent of the rose;

Not the sky, but the light in the sky;

Not the fly, but the gleam of the fly:

Not the sea, but the sound of the sea;

Not myself, but what makes me

See, hear, and feel something that prose

Cannot: and what it is, who knows?

1.It denotes prose?

2.What is the main verb of the subject prose? (prose cannot V something)