"I wanted to write the book about me. Here's my life."
Speaking on This Morning, Stahl offered her take on why Schwarzenegger decided to reveal intimate details of his personal life in the book.
"He's trying to get a fourth act," she said. "He's working on what's next. This was going to help him launch whatever is next [but] the scandal became public. He was basically forced to write about it."
Publisher Simon & Schuster claims that Schwarzenegger started working on the book before he publicly admitted in May 2011 to fathering a child with Baena.
"He wanted to write a book about his career. He is one of the only people you can think of who got to the top three different times. Most of the book is about how he did it. He did it three times," she added.
"He's a man of drive, endurance, almost inhuman persistence. That's what the book is supposed to be about."
Check out a preview of the interview below:
In a TV promo for the memoir that surfaced last week, the actor declared: "If my life was a movie no-one would believe it, the directions I've chosen, the careers I have conquered. This story you know. So are you ready for the story you don't?"
The 624-page book is released on October 1, and chronicles Arnie's rise from Austrian bodybuilder to action hero to governor of California.
But there's one chapter in particular, called The Secret, that's grabbing all the attention.
It details the moment Shriver, 56, confronted Schwarzenegger about the secret love child he had with Baena.
On January 4, 2011, the day after his term as governor expired, Shriver secretly booked a couples' counselling session and blindsided her husband by confronting him about the child.
"The minute we sat down, the therapist turned to me and said, 'Maria wanted to come here today and to ask about a child - whether you fathered a child with your housekeeper Mildred," he writes in the book, according to ABC News. "I told the therapist, 'It's true'."
The actor admits to grovelling for his wife's forgiveness, telling her that he "screwed up", calling her "the perfect wife" who still turned him on.
His grovelling didn't work. The couple announced their separation on May 9, 2011. Shriver filed for divorce on July 1, citing "irreconcilable differences".
'YOU CAN CALL THIS DENIAL'
Schwarzenegger also reportedly writes that he fathered the child, Joseph, after a tryst in the family guest house in 1996, while he was filming Batman & Robin and his wife and four kids were away on holiday.
He tried to convince himself that Baena's son was not biologically his, but as the child grew older, his resemblance to the actor couldn't be denied.
"I realised there was little doubt that he was my son," he writes.
He said that he kept the affair a secret because he was embarrassed, and because he did not want to face Shriver's family, the Kennedys.
"Instead of doing the right thing, I'd just put the truth in a mental compartment and locked it up where I didn't deal with it every day," he writes.
The star also reportedly blames his own arrogance in believing "you'll get away with ignoring the rules" for the affair.
In the book, the star also says that he still hopes to one day reunite with Shriver.
"You can call this denial," he writes. "But it's the way my mind works."
Schwarzenegger's interview with 60 Minutes airs in the US on Sunday.
FAST GOSSIP
And finally...
* Chris Brown tests positive for marijuana, still on probation.
* Beyonce pregnant again? "It's not true right now", but, "It's gonna happen," says her mother.
* Sheriff's office to Fiona Apple: "Just shut up and sing".
* Sarah Michelle Gellar and Freddie Prinze Jr. welcome baby boy.
* Hollywood is officially out of original ideas: Total Recall director in talks to helm Universal's The Mummy reboot.
* Miley Cyrus working on "sick" new album for early 2013 release.
* Lindsay Lohan hospitalised for asthma.
* Simon Cowell romancing Carmen Electra?
* Judge dismisses $10m lawsuit against Jennifer Lopez.
* Vanessa Paradis dating Carla Bruni's ex Benjamin Biolay, rumour says.
* Russell Brand blames Katy Perry divorce on "incompatibility", ex says women can't resist his "sexual energy".
* Lana Del Rey releases Born to Die: Paradise Edition artwork and promo trailer:
Click on over to NME for more details on the release.
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- Rumour Has It
