The Thing in the Attic by James Blish, Science Fiction, Fantasy

It is written that after the Giants came to Tellura from the far stars, they abode a while, and looked upon the surface of the land, and found it wanting, and of evil omen. Therefore did they make men to live always in the air and in the sunlight, and in the light of the stars, that he would be reminded of them. And the Giants abode yet a while, and taught men to speak, and to write, and to weave, and to do many things which are needful to do, of which the writings speak. And thereafter they departed to the far stars, saying, Take this world as your own, and though we shall return, fear not, for it is yours.
-THE BOOK OF LAWS