The traditional view of the sanctity of human life will collapse under pressure from scientific, technological and demographic developments.

History is not going to look kindly on us if we just keep our head in the sand on armed autonomous robotics issue because it sounds too science fiction.

Cheats prosper until there are enough who bear grudges against them to make sure they do not prosper.

I honestly don't know, but if America continues to refuse to reduce its greenhouse gas emissions, I see a bleak future not only for American society, but for the world as a whole. This is a global problem that is not going away, and the United States is an obstacle to solving it.

Take for example providing a guide dog for a blind person. That's a good thing to do, right? All right. It is a good thing to do. But you have to think what else you could do with the resources. It costs about $40,000 to train a guide dog and train the recipient so that the guide dog can be an effective help to a blind person. It costs somewhere between 20 and $50 to cure a blind person in a developing country if they have trachoma. So you do the sums, and you could provide one guide dog for one blind American or you could cure between 400 and 2,000 people of blindness.

If they [animals] were really to get the equal consideration that I believe they should, we wouldn't have commercial animal production in this country.

We need to recognise that what really matters isn't buying more and more consumer goods, but family, friends, and knowing that we are doing something worthwhile with our lives. Helping to reduce the appalling consequences of world poverty should be part of that reassessment.