Michael J. Fox has never let Parkinson's break his spirit.
The Back to the Future star sat down with AARP Magazine for the publication's April/May issue, where he candidly discussed how accepting his condition has led to him living a more fulfilled life.
"It isn't resignation, and it freed me to actively deal with and endeavor to change my situation," the 55-year-old actor said of coming to terms with his illness. "I like to say, 'My happiness goes in direct proportion to my acceptance, and in inverse proportion to my expectations.'"
In fact, Fox says that going public about his diagnosis is what has helped him to live a happier life.
"It was empowering to have people understand what I was going through," he shared. "I immediately felt better."
Another thing that enriches the actor's life? Staying active.
"We've learned [exercise] will prolong your ability to operate positively in the world," Fox revealed. "It helps me think -- the physical motion creates intellectual motion."
All these years on, Fox believes that humor and optimism are key to battling the disease.
"I hate when people say, 'You're giving them false hope,'" he said, addressing critics of optimism. "To me, hope is informed optimism."
"I laugh at [my involuntary movements and the scenes they create]. There are times when I love these things," Fox said, going into detail about a recent breakfast he had with his wife.
"Just the other morning I come into the kitchen. 'Oh, good, coffee. I'm gonna get some! No, wait – I'm gonna get some for Tracy,' -- who's at the table with the paper," Fox told. "I pour a cup -- a little trouble there. Then I put both hands around the cup. She's watching. 'Can I get that for you, dear?' 'Nah, I got it!' Then I begin this trek across the kitchen. It starts off bad. Only gets worse. Hot java's sloshing onto my hands, onto the floor…"
To Fox, the situation is so funny, but what he finds particularly comedic is thinking about those who find it sad.
"The thing that makes it hilarious to me is when I think of someone else watching all this and thinking, 'Poor Michael can't even get the coffee – it's so sad!'" he shared.
Really, as Fox explains, the biggest part of dealing with Parkinson's is mental, more so than painful.
"My visible symptoms are distracting, but none of them hurt," he shared.
During the interview, Fox also talked about a conversation he had with Muhammad Ali -- who died last year after his own 32-year battle with Parkinson's.
"Muhammad Ali called me at home," Fox said. "And in this raspy, paper-thin voice, he said, 'Aahhhhh … Michael, now that you're in it, we'll win this fight.' What could I say? Sitting there alone listening to Muhammad Ali, this giant -- I was welling up, almost openly weeping."
Meanwhile, Fox received a standing ovation earlier this year during his surprise appearance at the Academy Awards.
Watch the video below for more.