The `Hot Fuzz` actor admits his favourite book of all time was one his mother gave him when he was 12, which described the secrets of sex to him and taught him things about his appendage he didn`t know.
He told NME magazine: "The book that changed me was `The Facts of Love by Alex and Jane Comfort`. It was the children`s version of `The Joy of Sex` which my mum gave me when I was 12. It changed me a lot because I learnt more about what was going where. I was in my bedroom going, `The penis does WHAT?` "
Simon now has a 15-month-old daughter with his spouse Maureen Pegg, and has just finished penning his autobiography, `Nerd Do Well`.
However, he is concerned about which other stars he will be competing with for sales.
He added: "I`ve got competition from Carl Barat on the memoir front, haven`t I? Well, I probably won`t have as many Pete Doherty stories as him. I haven`t heard from Pete in a while. Is he still working or is he in rehab forever? I`m so out of touch."