Hymn to Intellectual Beauty  [first stanza]

The awful shadow of some unseen Power
   Floats though unseen among us; visiting
   This various world with as inconstant wing
As summer winds that creep from flower to flower;
Like moonbeams that behind some piny mountain shower,
   It visits with inconstant glance
   Each human heart and countenance;
Like hues and harmonies of evening,
   Like clouds in starlight widely spread,
   Like memory of music fled,
   Like aught that for its grace may be
Dear, and yet dearer for its mystery.

...

- Percy Bysshe Shelley (1792-1822)