IT may be for the world of weeds and tares
And dearth in Nature of sweet Beauty's rose
That oft as Fortune from ten thousand shows
One from the train of Love's true courtiers
Straightway on him who gazes, unawares,
Deep wonder seizes and swift trembling grows,
Reft by that sight of purpose and repose,
Hardly its weight his fainting breast upbears.
Then on the soul from some ancestral place
Floods back remembrance of its heavenly birth,
When, in the light of that serener sphere,
It saw ideal beauty face to face
That through the forms of this our meaner Earth
Shines with a beam less steadfast and less clear.

Alan Seeger

http://www.poemhunter.com/poem/sonnet-xiv-3/