Carbon dioxide is unusual because it doesn't go through the usual three phases of matter, from solid to liquid to gas, but it goes straight from solid to gas. The volume of the gas is much greater than the volume of the solid. When a solid turns into a gas, we say it sublimes. The process is sublimation.

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.

Having a child is arguably the most important thing you do in life.

We live longer and healthier lives than ever before. Animal research has improved the treatment of infections, helped with immunisation, improved cancer treatment and had a big impact on managing heart disease, brain disorders, arthritis and transplantation.

It's extraordinary to think that if you walked into a room and said you had never heard of Hamlet, you would be regarded as a Philistine. But you could walk into the same room and say, 'I don't know what a proton is,' and people would just laugh and say, 'Why should you know?'

Ethics is not routinely taught to science students except in medicine, and I think it should be.

Religion has endured since the dawn of human consciousness precisely because it encompasses so much of being human. No idea has endured so long, gathered up so many disparate needs and wants and feelings, and inspired so many different paths towards understanding it.