I put a lot of effort into writing 'A Briefer History' at a time when I was critically ill with pneumonia because I think that it's important for scientists to explain their work, particularly in cosmology. This now answers many questions once asked of religion.

A picture is worth a thousand words...and uses up a thousand times the memory.

The more you learn, the more you know. The more you know, the more you forget. The more you forget, the less you know. So why bother to learn.

Real science can be far stranger than science fiction and much more satisfying.

As we shall see, the concept of time has no meaning before the beginning of the universe. This was first pointed out by St. Augustine. When asked: What did God do before he created the universe? Augustine didn't reply: He was preparing Hell for people who asked such questions. Instead, he said that time was a property of the universe that God created, and that time did not exist before the beginning of the universe.

With genetic engineering, we will be able to increase the complexity of our DNA, and improve the human race. But it will be a slow process, because one will have to wait about 18 years to see the effect of changes to the genetic code. By contrast, computers double their speed and memories every 18 months. There is a real danger that computers will develop intelligence and take over. We urgently need to develop direct connections to the brain so that computers can add to human intelligence rather than be in opposition.

I'm very interested in film making. It's telling a story, fiction or non-fiction. I have been filmed quite a lot. Contrary to popular belief, filming isn't glamorous. It can be wearingly repetitious, as the same shot is taken over and over again.