Van Gogh was very crazy. Lust for Life understated it.

When Vincent van Gogh walked down the street, urchins screamed “nutter,” and their parents said, “The madman is at it again.” His father tried to have the young Vincent committed, and his mother later summed things up neatly: “I believe he has always been insane, and that his suffering and ours was a result of it.” Van Gogh himself ranted and raved, ate paint, drank turpentine—and slashed off a chunk of his ear. “I felt my own disease very deep within me,” he said in a moment of calm.