T.C. Boyle says he has done every kind of drug. But that is not his addiction.

The author last month released his 17th novel in a span of four decades, “Outside Looking In,” set at Harvard in the early 1960s, where Timothy Leary and his grad student acolytes are doing research Saturday nights with LSD. Boyle has written hundreds of short stories (one recent story, “Asleep at the Wheel,” was for the New Yorker, which he reads out loud on the magazine’s website in a voice that always sounds just one beat shy of a grin). The man is prolific, but not because of monkish discipline. He’s prolific because, even as he just rounded his 70th birthday, he can’t stop.

“Writing is a habit, an addiction, as powerful and overmastering an urge as putting a bottle to your lips or a spike in your arm,” Boyle wrote in a 1999 essay, “My Monkey, My Back” — a reference to heroin addiction.

I began my own addiction to Boyle in the mid-1980s, when I was a magazine writer covering chunks of California and looking for role models: writers who were capturing the zany-chill, utopia-aspiring, apocalyptic West Coast state of mind. Boyle told stories — in “Budding Prospects,” set in the marijuana grows of Mendocino, and in “Tortilla Curtain,” set in Topanga Canyon amid wealth, migration and fire — that did just that. He also warmly loved his characters, often young idealists who tripped over their own earnest feet. Finally, he was funny. Among literary writers tracking the zeitgeist, funny was, and is, rare.

Boyle isn’t from California, though he’s lived here since 1978 when he arrived to teach at USC. He grew up near blue-collar Peekskill, N.Y., north of New York City and off the Hudson River, and he’s often characterized himself as a bit of a punk as a young man. His signature book jacket look remains a subversive T-shirt under a jacket and a devilish goatee. This is a bit of punk branding; Boyle studied with Cheever and Carver and others at the Iowa Writers Workshop and has a doctorate in literature — perfect credentials for a tenured position at a university.

But while Boyle is not originally from the West, and while “Outside Looking In” never comes anywhere near California, I think of him as one of us. His work is cut through with those characters who populate so many of our California myths: the commune dwellers, health seekers, cult followers, everyday hustlers. As he does in many of his novels, Boyle weaves fictional characters — in this case, psychology grad students — with real, historical figures — in this case, Leary. He does so because he’s getting at the questions that occupied real people of earlier eras — How do you find God? Does love last? Is science benign? — that still occupy us now.

On the promotion tour for “Outside,” Boyle came to The San Francisco Chronicle to talk about the book, of course, but also to record a wide-ranging podcast that touched on his early life, his fondness for San Francisco and the horrible days when fire, then flood took out many of his neighbors last winter near his home in Santa Barbara County. (You can hear the whole podcast here.)

Asked about why his novel centered on Leary, Boyle says he wanted to explore the time before his own time in the late ’60s and ’70s, to see how we got to what became a cultural revolution. Boyle had thought of Leary as “this preposterous figure, an old guy on TV muttering, brain dead, in a toga. We were in possession of the truth, we were the real deal. So it was so great to see him as he was then, before all this happened. How did we get to Jimi Hendrix? Would there have been hippies if Albert Hofmann hadn’t invented acid and Leary hadn’t proselytized for it? I wanted to go back to try to find out.”

As pleasurable as Boyle’s fiction always is, it’s never just about the characters, the plot, the scene-setting, the humor and farce. It’s always about going back to figure out how we got here. After now 28 books, Boyle is still addicted to figuring that out.