In 1970, John Baldessari was teaching studio art at Cal Arts, while enduring a crisis of faith in his own semi-abstracts. He took everything he’d ever made to a San Diego mortuary and cremated it, baked the ashes into cookies, stuffed them into a bronze urn shaped like a book, then engraved a plaque with the destroyed paintings’ birth and death dates and the recipe for the cookies. “It was a very public and symbolic act,” he said, “like announcing you’re going on a diet in order to stick to it.”