I HAVE drunk ale from the Country of the Young
And weep because I know all things now:
I have been a hazel-tree, and they hung
The Pilot Star and the Crooked Plough
Among my leaves in times out of mind:
I became a rush that horses tread:
I became a man, a hater of the wind,
Knowing one, out of all things, alone, that his head
May not lie on the breast nor his lips on thc hair
Of the woman that he loves, until he dies.
O beast of the wilderness, bird of the air,
Must I endure your amorous cries?

William Butler Yeats

http://www.poemhunter.com/poem/he-thinks-of-his-past-greatness-when-a-part-of-t/