“I’m always interested in things that we don’t call art,” the late conceptual artist John Baldessari says in an episode of Art21’s Art in the Twenty-First Century series. The artist, who died this week in California at the age of 88, appeared on an episode highlighting “Systems” back in 2009, and explained his career-long quest to upend the conventions of what constitutes art in the first place.

“All of a sudden, because I said it’s art, somebody believes me!” He says, laughing. Indeed, the California-based artist viewed the world, and the art within it, with a healthy dose of skepticism and wit. Baldessari’s practice included mixing found images sourced from textbooks, magazines, and advertisements with disparate words or sentences. The works could be read as either a humorous juxtaposition, or on a deeper level, as a criticism of the institutionalization of art education and the commodification of art. “If you’re looking at two things, don’t look at them… look between them, because there’s that stuff too.”

Production still from the “Art in the Twenty-First Century” Season 5 episode, “Systems,” 2009. © Art21, Inc. 2009.

In the interview, which follows the artist around his studio as he prepared for the inaugural exhibition at LA’s Broad Contemporary Art Museum, Baldessari credits his sister for encouraging him to get a teaching degree—just in case the whole art thing didn’t work out.

In the end, that was his saving grace, sharing his distinct perspective with students at the distinguished Cal Arts program and later at UCLA. The interview includes commentary from the artist Amalia Saban, who back in 2009 worked as an assistant to Baldessari. “I think he taught me to be human when it comes to the work… there is something very humble about the way he works, it’s a lifetime commitment to the work.”