Michael J. Fox doesn’t let Parkinson’s disease get him down. He takes life step-by-step when he fears he will fall, he laughs through hardship, and he helps others who are struggling to do the same.

“I don’t know much about acting, but I know what people have told me and what acting teachers have told me,” he said. “I learned that if you’re laughing, just keep laughing, if you’re crying, cry till you cant anymore. Stuff happens and you just get on.”

When old friends Denis Leary and Fox sat down for a Tribeca Film Festival panel talk on Tuesday, they shared memories and quipped about how they’re different: the former is a pessimistic Irishman, the latter an optimist with a dark sense of humor. From Fox joking about how disabled people can also be “assholes” to retelling a story about how his daughters had to describe the term “fomo” to him, it seems to be true. In Leary’s case, he said that his Manhattan road-rage is his favorite part of the day.

“I consider myself an Irish optimist, which means I look forward to the worst happening, but you, you’re sort of unrelenting. Like you know, with this disease or this diagnosis, you go like ‘okay, what’s the next f—ing barrier that comes up, f— that, let’s knock it down,’ which is really admirable,” Leary said.

A tangible indication of Fox’s humorous optimism can be shown through his comedy show fundraiser, “A Funny Thing Happened on the Way to Cure Parkinson’s,” which are followed by another one of Fox’s passions: music. The events have seen acts and guests such as Chris Rock, Muhammad Ali, Whoopi Goldberg, and magician David Blaine. Leary recalled one story where Ali hid from Fox in a janitor’s closet because his attendance was supposed to be a surprise. Every year, Fox also achieves his rockstar dreams by appearing onstage playing his guitar.

“Every year when Mike does the event, it ends with rock and roll,” Leary said. “Elvis Costello, The Who, every year there’s this big number and Mike is playing ‘Johnny B Goode,’ so in your own way, your rockstar dreams are achieved.”

In terms of how The Michael J. Fox Foundation for Parkinson’s research is going, he said that they are on their way to “zoning in” on figuring out how to catch symptoms early. They have enough indicators that will help folks treat the symptoms more proactively before the cells start to die, and he said that they will make feasible steps toward prevention within a few years.

“After spinal surgery, it was hard to learn how to walk. I was really cocky about it and walking with no aids or cane, and then I shattered my humerus, which is no f—ing joke, think about it,” he said about his struggles. “I was the guy who made lemonade out of lemons, but I couldn’t make lemonade. Then I realized I have to take everything one step at a time so I don’t fall down. You have more time that way. Each step is a new adventure.”

Fox ended saying that he’s working on his next book, which he jokingly said would be called “Why We Don’t Suck,” and gave advice to young actors: “brush your teeth.”