Paul Davies

Astonishingly, in spite of decades of research, there is no agreed theory of cancer, no explanation for why, inside almost all healthy cells, there lurks a highly efficient cancer subroutine that can be activated by a variety of agents - radiation, chemicals, inflammation and infection.

A permanent base on Mars would have a number of advantages beyond being a bonanza for planetary science and geology. If, as some evidence suggests, exotic micro-organisms have arisen independently of terrestrial life, studying them could revolutionise biology, medicine and biotechnology.

Every time I see documentaries or infomercials about little kids with cancer, I just freak out. It affects me on the highest emotional level... Anytime I think about it, it makes me sadder than anything I can think of.

I have friends of mine that are actors or singers, and they're the classic guys where, they're onstage, and they're like, 'Okay, the blonde in the third row, seat 24, bring her to my dressing room.' I've never, never taken advantage of that, I swear to God.