Speaking to Hello! Canada, the Oscar winner revealed that the early birth of his youngest daughter Stella took him and wife Luciana by surprise.
"It's been pretty crazy. The baby came a couple of weeks early. It's our fourth, so we've done it before - but it's a whole new dynamic," he said.
Damon also remarked that overcoming the many demands of fatherhood requires a detailed plan of action.
"In terms of juggling responsibilities, you're going, 'I'll do that. No problem, I'll do that'. After a week you go, 'Wait a minute! We have to figure out a plan here'. The girls… all require different things."
He concluded: "It was very different, it's true, but I can't imagine my life having not gone down that road. I can't imagine what my life would be now. I don't want to imagine it."