What does a rock pile ceases to be a rock pile the moment a single man contemplates it bearing within him the image of a cathedral mean

This phrase probably has more to do with philosophy than geology, and hints at the ability, whether sensible or not, of human beings to turn anything, or nothing at all, into a thing of worship, be it a rockpile, a book of questionable stories, or another human being. Cathedrals themselves are little more than piles of rock laid in an orderly fashion; that they are holy is purely in the mind of the individual.