The 'Elysium' actor has four girls, Isabella, Stella, Gia and stepdaughter Alexia, with his wife Luciana Barroso, and he believes he is in a unique position because he gets to see the world through their female eyes.
He said: "I'm lucky to be the only guy in the house. It's a man's dream. The testosterone deficit at home makes me very special. You learn a lot by looking at the world from their point of view. I'm now convinced we're different species, more than I thought before."
The 42-year-old star says his young daughters aren't fully aware of their dad's Hollywood stardom, but Alexia, 14, has begun to understand her stepdad is a big deal on the big screen.
Quizzed if his daughters know he's an actor, he told Red Bulleting magazine: "I don't know what that'll happen, but when it does it will happen by osmosis. Alexia heard stuff at school and started asking questions.
"But by that point the whole thing had been so demystified. They've been on movie sets, they've seen that process and they've met all kinds of people who work in the business. They say things like, 'Uncle George is a movie star?' and I say, 'Yes, George Clooney is a star, believe it or not.'