John Baldessari, the influential conceptual artist who helped transform Los Angeles into a global art capital through his witty image-making and decades of teaching there, died on Thursday at his home in the Venice neighborhood of Los Angeles. He was 88. His death was confirmed on Sunday by Virginia Gatelein, his studio manager and the chairwoman of his foundation. No cause was given.

Mr. Baldessari started as a semiabstract painter in the 1950s but grew so disenchanted with his own handiwork — as well as the very notion of handiwork — that in 1970 he decided to take his paintings to a San Diego funeral home and cremate them. He was ready to embrace a wide range of mediums: videos, photography, prints, sculpture, text-based art, installations and, yes, paintings, but most of all hybrid forms of these, like text painting.