Well, he's already had a heads-up. From The Times:

A fan of Stephen Hawking has had the physicist's face tattooed on his right leg above the classic Monty Python line: "He's not the Messiah. He's a very naughty boy."

Jack Newton, 23,  [any relation to Isaac? M.J.] a trainee tattooist from Brighton, said: "I read A Brief History of Time, but to be honest I didn't understand a word. But I respect the man and he's a great inspiration to us all." The work has already won two trophies at tattoo conventions.

Tattoos and learning don't usually mix - unless those men with "I love mum" tattoos are closet Sophocles fans. I once saw a man in a pub with patches on each knee of his jeans. One patch said "Scylla" and the other "Charybdis". I refused to be drawn in.