There were never any doctors in my family. But my grandparents and my mother had a strong social conscience that was formative.

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.

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

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.

Now we have technology where we can modify the genomics of individuals by gene transfer and genetic meddling, we may find that people will want to modify their children, enhance their intelligence, their strength and their beauty and all the other so-called desirable characteristics.

Childhood is not dead. Children were worse off when we were hunter-gatherers; they were threatened in medieval times and exploited during the Industrial Revolution. Was it any better in the time of Charles Kingsley or Charles Dickens?

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.