Michael J. Fox likes to call himself an optimist, but in his new memoir, he is realistic as well. Recognizing the state of his health after decades with Parkinson’s disease — Fox was first diagnosed in his late 20s — the star of Back to the Future and Spin City says he is retiring from acting — “at least for now.”

That’s according to an excerpt from the book quoted in the Los Angeles Times, which describes Fox’s latest autobiography as “sober” in its self-assessment of the actor and author’s health. Here is what Fox says about his career in front of the camera:

There is a time for everything, and my time of putting in a twelve-hour workday, and memorizing seven pages of dialogue, is best behind me ... At least for now ... I enter a second retirement. That could change, because everything changes. But if this is the end of my acting career, so be it.

According to the Times, Fox also goes into detail in the book about “cognitive changes” brought on by Parkinson’s disease “including memory loss, confusion, delusions and dementia...he describes looking for his car keys before remembering he can no longer drive.”

It’s tough to read those words about an actor who has brought so much joy to so many people, and who’s done so much good for the world through The Michael J. Fox Foundation for Parkinson's Research. Fox’s new book, No Time Like the Future: An Optimist Considers Mortality, is on sale now.

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