I think that good parenting should allow children to be children. That naivety and slightly open way of looking at the world is very valuable.

Women of child-bearing age steadily run out of eggs by the continuous process of cell death. While reading a copy of the Guardian carefully from cover to cover, a normal woman will have lost on average two eggs - while, typically, a normal man will have made 70,000 new sperm.

The trouble with climate change is it's an extraordinarily diverse and complex issue, but for example if the BBC would let me make some of the programmes I'd like to make on climate change, I bet you there would be a change of emphasis.

Parents should talk to their children, even when they are babies and can't talk back.

I'm a traditional Jew with an orthodox background, and it informs much of my approach to science. Of course I think it's very important that if you have those sorts of backgrounds you don't impose them on other people as a clinician, of course.

When I look in the mirror, I am slightly reminded of self-portraits by Durer and by Rembrandt, because they both show a degree of introspection. I see some element of disappointment; I see a sense of humour, but also something that is faintly ridiculous; and I see somebody who is frightened of being found out and thought lightweight.

I remember eating in school in the years after the Second World War. Most of my friends had miserable portions of Spam with an inedible, glutinous pudding served in containers we called 'coffins.' As a vegetarian, I had a lump of loathsome cheese and some bread.