It was when he was 58 and the Commissioning Editor for BBC Radio 4 Comedy, that Paul noticed that his handwriting was getting smaller and his arms weren't moving normally when he walked.
He was diagnosed with Parkinson's, but he didn't think of it as the end of the world.
Instead he thought of it as an opportunity for jokes which he could share with others in the same leaky boat and make them all feel better.
Two years ago, he made a documentary called Parkinson's: The Funny Side for which he won the Grierson Award for Best Documentary Presenter of the Year.
"Laughing at my Parkinson's has enabled me to start talking about it properly.
"It's allowed me to have the kind of conversations that I wish I'd been able to have with my mother, who had cancer throughout my teenage years and died when I was 20.
"We never talked about it, and I didn't know that she was dying. It's for this reason that I choose to focus on the non-serious bits of my illness. I want to leave some joyous memories that my family can enjoy long after I've gone."
But then Paul knows a bit about comedy…
He's been writing it all his life - from puppet shows for his friends at the age of ten to The Vicar of Dibley.
He's produced hundreds of episodes of radio comedy including I'm Sorry I Haven't a Clue, Weekending (starring David Jason), Delve Special (starring Stephen Fry) and two award-winning shows written and performed by Andy Hamilton - The Million Pound Radio Show and Old Harry's Game.
In 1987, Paul wrote his first sitcom for radio, An Actor's Life For Me and it did so well that it transferred to BBC One where Richard Curtis saw it and asked Paul to work with him on a series about a woman vicar in a village full of lunatics – and the rest is history!
As if that's not enough, Paul has also script edited many TV series including Spitting Image, Two Pints of Lager and a Packet of Crisps and Miranda, and he's co-written episodes of My Hero, Mrs Brown's Boys and the TV film Roald Dahl's Esio Trot starring Dustin Hoffman and Judi Dench.
Paul Mayhew-Archer : Incurable Optimist at Komedia Brighton on Saturday 4th and Sunday 5th May 2019 - www.komedia.co.uk/brighton / 01273 647100.