Starring as a psychic who sees dead people in Clint Eastwood's Hereafter forced Matt Damon to question whether or not there's an afterlife.
"I'm hopeful. But who knows? Maybe the light does just goes off," he says today. "But we'll all find out sooner or later, that's for sure."
Wed five years to Argentinian-born barmaid Luciana Barroso, Damon became an instant dad to her daughter Alexia, now 12, and together the couple are now also parents to girls Isabella, four; Gia, two, and three-month-old Stella.
Exchanging bachelorhood for his present-day status as father-of-four within just eight short years has certainly caused him to contemplate the meaning of life and death more than he would have otherwise. "I think having children adds a whole other layer of where you start thinking a little deeper about your mortality," says the actor, who recently turned 40, indicating his prematurely-greying hair. "The grey hair I definitely attribute to my kids. I always say to them – this [grey hair] is all you and this side here is you!"
Not that he fears ageing. "Clint makes the other side of the hill look pretty appealing. I was doing an interview for Invictus a year ago with Morgan [Freeman] and when somebody mentioned I was going to be 40, Morgan said that I was coming into the best two decades of my life. So to see guys that I really admire say that – and as vigorous as those guys are – it wasn't a big traumatic thing. Maybe I'm gonna freak out or something, but it hasn't happened yet," he says, smiling good-naturedly, looking today like he's stepped from the pages of a preppy men's fashion catalogue with his cashmere sweater, jeans and spectacles.
Just 26 years old when he and writing partner and co-star Ben Affleck took home the Best Original Screenplay Oscar for Good Will Hunting, the childhood best friends were bursting with promise. It was a potential that could have led them anywhere – or, most likely scenario, that just one of the dynamic duo would succeed. But the movie gods were shining on them both, each going on to enjoy great success, Affleck recently receiving much acclaim for The Town, a film he directed, wrote and starred in.
Or, as Affleck put it a few months ago while attending the Toronto Film Festival: "It's pretty amazing that we're both here. Me with The Town and Matt with Clint Eastwood. It's actually quite mind-blowing."
Damon isn't any less humbled by his success. He's actively involved in charitable work, including the ONE Campaign and grateful for a career in which he's starred in such critically acclaimed films as Saving Private Ryan, Syriana, The Informant and The Departed as well as box-office pleasers like The Bourne trilogy and Ocean's Eleven, Twelve and Thirteen.
But he's clearly found a rhythm with Clint Eastwood, whom he views as a mentor despite Hereafter only being their second film together.
"I hope this is the second of 10 movies with Clint. I was really happy he called. He didn't even have to give me such a wonderful script. He could have called with anything really and I would have done it," says Damon, who smiles modestly when you point out how Eastwood even re-scheduled the film's shoot in order to accommodate the actor's other film commitments.
One of the most down-to-earth actors in Hollywood, it's easy to see why he would find an easy shorthand with Eastwood, a similarly gentle soul.
"There's just so many reasons why working with Clint is special. He's been making movies for 60 years and has such an incredible depth of knowledge. He really knows how to do everybody on the set's job better than they do.
"And yet he doesn't control that way, and he hires wonderful people and then creates an environment where they can do their best work and they have a good deal of creative control.
"The director is the hardest job in movie-making and the one with the most responsibility. It's like three-dimensional chess. But his identity has never been wrapped up in what the business thinks about him. It's pretty Zen, if you think about it," he says.
Reflecting on his own childhood, which was likewise "pretty Zen", the Cambridge, Massachusetts-born actor says, "I was lucky in that I grew up in an environment where I didn't need to [get into fights]. My mother is a professor of non-violent conflict resolution and early-childhood education and so we were encouraged to work out our problems through discussion."
The son of stockbroker Kent Damon and mother Nancy Carlsson-Paige, his parents divorced when he was two, from which time he spent some of his childhood with his mother living in a commune.
Having interviewed Damon frequently, I've noticed that it's his mother whom he references, rather than his father. When discussing Eastwood's casting of twin British boys in Hereafter, for example, he says his mother had noted how the director always coaxes impeccable performances from his young actors. Damon, though, is in no rush to put his own kids before the camera, saying: "Raising my girls to be strong, good women – that's my main focus. If they show any interest in acting, I think I'd only want them to do it if I was behind the camera."
If most actors will pretend to have some kind of affinity toward the subjects they portray, then Damon is sceptical about psychics. "I've never had what one might describe as an other-worldly experience. I simply haven't. I feel like my life is like a miracle, but nothing like a premonition or anything remotely psychic," says the actor, who also refused to visit any real-life psychics in preparation for the role.
"I didn't, no. Had I found a good one, I would have. What I was worried about was that it was just going to take me down this rabbit hole of charlatans. I think a large part of that space is occupied by pretenders, which is not to say there aren't people there who are genuinely touched in some way. I just didn't get a chance to meet any of them.
"But I did speak to Martin Sheen, who had a near-death experience on Apocalypse Now when he had a heart attack. He told me his incredible story one day when we were working on The Departed together. It's a very well-catalogued experience that a lot of people have had. One person I read about was legally dead for 28 minutes, which I think is the record."
Learning about such near-death experiences, he says, has resulted in a lessening of his own fears of death.
"It's interesting. I assume most people are afraid of death, but the people who've had these experiences aren't. That seems to be one of the things they have in common – that they don't have any fear of it any more."
One of few Hollywood stars who chooses not to maintain a presence in Los Angeles, the former ladies' man – who previously dated Winona Ryder, Minnie Driver and Penélope Cruz – today prefers to avoid the spotlight, living with his family in Miami. "I've made a conscious effort to stay away from all that stuff. I don't live in Los Angeles, so that helps. Most of the paparazzi live in LA. The only time my wife and I get followed is usually when we're in LA, so not living there is a big help in terms of staying out of the public eye. We live in Miami – and in Miami it's basically me and Shakira. I don't even have to compete with Ricky Martin because he sold his house," says the oft-voted "Sexiest Man Alive".
After witnessing the birth of three daughters, it's clear that Damon is no less in love with his wife now than he was the night he met her in the Miami club where she was working. "People say that thing about seeing someone across a crowded room. I swear to God that happened to me. Not to get too hokey, but it did, definitely. I was shocked. It was something very weird.
"Now maybe that's just kind of a retroactive re-imagining of what actually happened, but I genuinely feel like something incredible happened the first time I saw her."
Reflecting on what happened after that fateful evening, he says today: "I moved and suddenly she wasn't just my wife. It was also a four-year-old little girl who's now twelve. There was never a choice. It was just the way it was and I was happy for that. I can't imagine my life having not gone down that road, or what my life would be now otherwise. I don't want to imagine it.
"I'm working on enjoying the present. Seriously, I feel like my whole life I've been looking into the future. I keep getting hit now with the fact that life is so wonderful that I want to enjoy it. It goes by so fast."
Just 17 years old when he won his first role – a one-liner in the early Julia Roberts' film Mystic Pizza – soon after, he and Affleck moved to Hollywood, where the ensuing disappointment famously prompted them to write Good Will Hunting.
One of the busiest actors in the business, featuring in the upcoming films True Grit, The Adjustment Bureau and Contagion and presently in pre-production for Liberace starring Michael Douglas, and We Bought a Zoo with Scarlett Johansson, 2011 is the year he plans to reunite with Affleck.
"We've been talking about it for years, so hopefully we'll get to do it," says Damon, rumoured to be co-starring with Affleck in an untitled legal drama later this year. "But we also want to make our own film. We've been trying to work together again for 10 years now, but life has taken us in different directions. Having small kids is big. Most of your energy goes there. Having small kids and living in different cities just means that you don't see each other a lot.
"I'd seen Ben's film The Town a number of times before it was finished, but then when it came out and just did so well I was so proud and happy. He dealt with a lot of shit for a lot of years that was unjustified and was the butt of a lot of jokes. So to watch all of those people who have to eat their words; he was a bigger man about it than I was. I'm petty enough to really care about that stuff and laugh at the demise of all these idiots that just don't know talent when they see it. He's now done something twice, which is really hard to do, which is come from nowhere and make a career for yourself in the movie business – which is available to anyone to try, anyone in America or anywhere in the world. They're welcome to try it. It's really hard to do and he did it with Good Will Hunting and then again with The Town, so he's in a very rare place now. There aren't many people who the industry views as just being able to pull an idea out of the air: write it, direct it and star in it.
"There haven't been many people historically who can do that. So it's great that he's in that place. So now I'm just looking for a job from him."
Ask Damon if he's following any kind of plan in his life, he scratches his head.
"That's the question, I think. I have no idea. I like to think that my choices matter, but I've certainly had such a good deal of luck in my life that it leaves me wondering sometimes."
'Hereafter' opens on 28 January; True Grit opens on 11 February