The actor explores life lessons in his new motivational book, ‘Be Useful: Seven Tools for Life,’ out Oct. 10

Arnold Schwarzenegger. PHOTO: MARK VON HOLDEN/VARIETY VIA GETTY

Arnold Schwarzenegger never expected to be a self-help guy.

But in the “fourth act” of his life, he’s been moved to distill some of his greatest life lessons into his new motivational book, Be Useful: Seven Tools for Life, out Oct. 10.

When it comes to his legacy, “everyone will have their own take on it,” he tells PEOPLE in this week’s issue.

“All I’m trying to do is just try to use my talents and help other people. It’s the simple stuff that I do that really helped me get where I am today.”

At 76, is he content? Over breakfast in Los Angeles, the sentiment doesn’t quite register with the star, who this year alone released his first live-action series, a documentary about his life called Arnold, a fitness-infused newsletter and a podcast called Arnold’s Pump Club.

“I don’t know what you mean by contentment,” he says. “I’m always content, but, I mean, I’m always hungry for more. I slept with my first trophy.

No one could take it away. But at the same time, the other foot is already out of bed going for the second Mr. Universe title.” (He went on to win three more, followed by seven Mr. Olympia titles.)

Schwarzenegger continues: “So today I feel good where I am. I feel I’m much wiser. I’m much smarter. I’m not as crazy. I think more about people.

I think more about people’s feelings. In your 20s, you don’t do any of that. It’s me, me, me, me. As time goes on, you learn from your mistakes.”

“Be useful” was Schwarzenegger’s mercurial father’s edict while he was growing up in the remote Austrian town of Thal, and the record-shattering bodybuilder-turned-global action star-turned ”Governator” of California co-opted it for the title of his new book, which recounts an austere childhood plagued by episodes in which his father would occasionally come home drunk and hit him.

From left: Chris Pratt, Katherine Schwarzenegger, Arnold Schwarzenegger and Christina Schwarzenegger in May.AXELLE/BAUER-GRIFFIN/FILMMAGIC

Schwarzenegger still wakes up at dawn with his father’s phrase prompting him out of bed. “It was the very phrase that motivated me,” he says. But he wouldn’t define his new book as closure.

“I was never looking for closure. I’m not into all this stuff, because I never really blamed my father for anything,” Schwarzenegger says. “I never ran around and said, ‘It’s my father’s fault.’ It’s nobody’s fault.”

“I have fond memories of my dad, and I don’t blame him for anything, simply because he did not know any better. He was beaten when he was a kid.

It was just a tradition. And then he was forced into [World War II], and was misled. He was growing up in an area where life was the way it was.”

Today the father of five — Katherine, 33, Christina, 32, Patrick, 30, and Christopher, 26, with ex Maria Shriver, and Joseph, 26, with Mildred Baena — is “really well bonded with my kids,” he says, and can often be found lifting weights with them at Gold’s Gym, where his body-building career began, or riding bikes around Santa Monica.

He’s also a grandfather now — or Opa, as he’s known to his daughter Katherine’s children Lyla, 3, and Eloise, 1, with her husband Chris Pratt.

When Lyla visits, she beelines for his animals, cuddling with his little dog Cherry and feeding the pig.

“I taught her how to feed the horses,” he says proudly. “She was scared in the beginning but she got used to it.”