On true wealth: an artist speaks of the invisible riches of the soul

I know that many will call this writing useless; these people, as far as I’m concerned, are like those whom Demetrius was talking about when he said that he cared no more for the wind that issued from their mouths in words than the wind that issued from their backsides. These men desire only material wealth and are utterly lacking in wisdom, which is the only true food and wealth for the soul. The soul is so much greater than the body, its riches so much nobler than those of the body. So, whenever a person of this sort picks up any of my works to read, I wonder if he will put it to his nose the way a monkey does, or ask me if it’s something edible.

Leonardo da Vinci, Notebooks