The 'Argo' actor-and-director is so contented with his wife Jennifer Garner and their children - Violet, six, Seraphina, three, and seven-month-old Samuel - that he isn't worried about getting older, especially since close friend Morgan Freeman, 75, thinks he is still young.
Ben told the Daily Mirror newspaper: "I'm lucky. I've got a good life. I've got three kids, I've been married for seven years, I just turned 40 and I finally feel, for better or for worse, like a grown up.
"I was talking to Morgan Freeman and I said, 'I'm turning 40', and he said, 'Boy, you're just coming into your prime.' I feel if Morgan said it, it's probably true."
The Hollywood star now lives near his close friend Matt Damon in the Pacific Palisades district in Los Angeles and the pair - who broke into showbusiness together and co-wrote the Oscar-winning 'Good Will Hunting' - like to organise play dates for their kids.
He said: "Matt lives down the street from me so I see him every day. We bring the kids back and forth and it's like fantasy-ville. We have a lot of friends who don't work in the movie business, thank God, otherwise the conversations would get very boring."
Despite shunning the limelight, he loves being married to fellow A-lister Jennifer and would love to direct her in a future film since he thinks she is a phenomenal actress.
Ben gushed: "I'd work with her in a second. If I found a movie with a strong female lead, I would love to direct her in it. She's a colossal talent and an extraordinary woman."