I don't believe in regretting - one should try to move on. My mum was good at that. She was deeply in love with my father, and he died when I was nine. She remarried, and her second husband died, too. I saw the grieving process she went through. My mother had this way of moving on. It was a fine trait.

Nearly all inventions are not recognised for their positive side either when they're made. So, for example, scientists didn't go out to design a CD machine: they designed a laser. But we got all sorts of things from a laser which we never remotely imagined, and we're still finding things for a laser to do.

In prehistoric times, Homo sapiens was deeply endangered. Early humans were less fleet of foot, with fewer natural weapons and less well-honed senses than all the predators that threatened them. Moreover, they were hampered in their movements by the need to protect their uniquely immature young - juicy meals for any hungry beast.

A young woman in her teens has about 300,000 eggs in her ovaries. By the time she is menopausal, none are left.

I don't like seeing myself on television and I don't enjoy filming. What I actually enjoy is thinking about how I am going to express something or how we are going to make the visual metaphor.

Medicine, which I wouldn't be without, has also been a force for... less good. For example, if you look at our mishandling of the immune system, using antibiotics in children and avoiding infection, we've certainly increased the risk of asthma.

I like travelling on my own. It means I'm completely free to think about what's around me.