"To my way of thinking, the concept drawings that Rembrandt did, the drawings he made that he used to model his artists, to work out the compositions of his paintings: those are cartoons. Look at his sketch for the return of the prodigal son. The expression on the angry younger brother's face. The head is down; the eyebrow is just one curved line over the eyes. It communicates in a very shorthand way. It's beautiful, expressive, and, in a peculiar way, it's more powerful than the kind of stilted, formalized expression in the final painting."