Sam Keen, a pop psychologist and philosopher whose best-selling book “Fire in the Belly: On Being a Man” urged men to get in touch with their primal masculinity and became a touchstone of the so-called men’s movement of the 1990s, died on March 19 in Oahu, Hawaii. He was 93.

His death, while on vacation, was confirmed by his wife, Patricia de Jong. The couple lived on a 60-acre ranch in Sonoma, Calif.

Mr. Keen, who described himself as having been “overeducated at Harvard and Princeton,” fled academia in the 1960s for California, where he led self-help workshops and wrote more than a dozen books. He became a well-known figure in the human potential movement of that era.

In the 1970s, he delivered lectures around the country with the mythology scholar Joseph Campbell. He also gave workshops at two of the wellsprings of the New Age: Esalen Institute in Big Sur, Calif., and Omega Institute in Rhinebeck, N.Y. Mr. Keen’s specialty was helping middle-class seekers slough off the expectations of family and society, and discover what he called their “personal mythology.”

A long conversation that the ruggedly handsome Mr. Keen had with the journalist Bill Moyers, broadcast on PBS in 1991, brought him national exposure the month that “Fire in the Belly” was published. The book spent 29 weeks on the New York Times best-seller list.