Whatever your talent or ambition, Harrison Ford has a simple charge: Put it to work.

The actor and Conservation International vice chair delivered that message Monday as commencement speaker at Arizona State University. The university had good reason to call: It recently launched the Rob Walton School of Conservation Futures in partnership with Conservation International , creating a training ground for the next generation of conservation leaders.

To the graduating class, Ford spoke of finding purpose to match your passion. His came relatively late in life, during a chance encounter with Conservation International that changed his worldview and his role as a storyteller.

“I hadn't found purpose higher than my job yet,” he said. “That changed in the late ’80s.…