Based on da Vinci’s work, there is evidence that the artist had strabismus: one eye is straight, while the other eye can drift. Some forms of strabismus are thought to facilitate artistic work by suppressing the deviating eye, which creates 2D monocular vision advantageous to painting and drawing.
John Lennon stubbed a cigarette out on a Henri Matisse painting while drunk at the Playboy Mansion, causing the painting to increase in value from its $15m price.
Students at Oberlin College can rent original paintings by Picasso, Monet, and Dalí (among others) to hang in their dorm rooms for $5 per semester. On top of the $5 each student has to cough up, only a minimal liability agreement is signed, although the full consequences for damaging a work are unknown to the renters.
There is the art movement called Accidentalism, in which a portrait is painted first, and only after the work is done a person is looked for that looks like the one in the painting. There are still portraits that have not found a subject yet.
After cutting off his ear, Vincent van Gogh painted a portrait of the doctor who treated him, then gave it to the doctor. The doctor hated it and used it to repair a chicken coop before giving it away. It’s now worth $50 million.
The figure in “The Scream” isn’t actually screaming; he’s listening to a scream passing through nature.