It is absurd to think that the only way to tell if a poem is lasting is to wait and see if it lasts. The right reader of a good poem can tell the moment it strikes him that he has taken an immortal wound – that he will never get over it. That is to say, permanence in poetry as in love is perceived instantly. It hasn’t to await the test of time. The proof of a poem is not that we have never forgotten it, but that we knew at sight that we never could forget it. There was a barb to it and a toxin that we owned to at once.