Source: This quote is from a Christian apologetics book “The Everlasting Man” (1925) by G. K. Chesterton; V: Man and Mythologies.

Complete Sentence: Sometimes it would seem that the Greeks believed above all things in reverence, only they had nobody to revere. But the point of the puzzle is this, that all this vagueness and variation arise from the fact that the whole thing began in fancy and in dreaming; and that there are no rules of architecture for a castle in the clouds.