O CLOUD-PALE eyelids, dream-dimmed eyes,
The poets labouring all their days
To build a perfect beauty in rhyme
Are overthrown by a woman's gaze
And by the unlabouring brood of the skies:
And therefore my heart will bow, when dew
Is dropping sleep, until God burn time,
Before the unlabouring stars and you.

William Butler Yeats

http://www.poemhunter.com/poem/he-tells-of-the-perfect-beauty/