I happened to see an interview recently with William Shatner, the actor who counts the dashing space cowboy Captain Kirk and the cranky lawyer Denny Crane among many roles.

His newest undertaking is a solo stage show, which looks like a cross between a dramatic monologue memoir and a motivational seminar. The clips I’ve heard show that beautiful Shatner multi-valence—as in all of the celebrated characters he has played, he is at once earnest, playful, self-parodying, and frank. He doesn’t court sentimentality, but he doesn’t steer away from emotion either. As he put it to the interviewer: “I’ve spent my whole life getting you to feel something!”

He’s interested in feeling, and the success of characters like James T Kirk and Denny Crane rests on the audience’s perception of the gap between what the character presents to the world and what the character is actually feeling. That irony creates depth. It allows us to feel kinship and empathy.

Shatner points out that engaging the full emotional complexity of a character is both exhausting and energizing. You have to drain everything, he says. It’s like the sink in the bathroom—you have to drain it out so you can refill it. But his whole philosophy rests on one basic principle: you have to have an on-going and unshakeable determination to say yes! to whatever presents itself.

This past spring, Shatner turned 82. I had to keep reminding myself of that as I watched him talk and laugh. He’s blunt, enthusiastic, and sharper than most. He doesn’t look artificially preserved—he looks alive and robust.

At one point in the conversation, the interviewer catalogued Shatner’s long career, pointing out that many actors don’t have a chance to accomplish so much over such a long span. After a long beat, he said, “Don’t you ever think about retiring?” Shatner’s eyebrows went up and he spread his hands in front of him. Then he shrugged, shook his head with genuine bewilderment, and said, “To what?!”I’m walking through my days now with that phrase, that inflection in my ear. Acting for someone like Shatner is not a job. It’s a way of engaging with himself—his appetite, his skills, his curiosity, his passion for others, his need for connection and approval, his desire to share his insights and knowledge. He’ll retire when he retires from life itself.

Meantime, he says yes!, draining himself out and filling himself back up again. I think we could all take a few lessons from that book.