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

Our aggression is a deep instinct which survives in all kinds of manifestations in modern man.

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.

My own field, the prevention of genetic disorders in babies, has been possible only because of humane work on animals.

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.

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

I've been all over the world on my own because, as a scientist, you travel a great deal if your work is reasonably successful or published. I get invitations to go to all sorts of strange countries where I would mostly be by myself and just meet other people there, instead of having travelling companions.