I believe that in this new world that we live in, we often have a responsibility, you know, to actually go beyond the thou shalt nots - that is, the not harming others - and say we can help others and we should be helping others.

One thing is certain: you will find plenty of worthwhile things to do. You will not be bored, or lack fulfillment in your life. Most important of all, you will know that you have not lived and died for nothing, because you will have become part of the great tradition of those who have responded to the amount of pain and suffering in the universe by trying to make the world a better place.

Of course, infanticide needs to be strictly legally controlled and rare - but it should not be ruled out, any more than abortion.

Even in the era of AIDS, sex raises no unique moral issues at all. Decisions about sex may involve considerations about honesty, concern for others, prudence, and so on, but there is nothing special about sex in this respect, for the same could be said of decisions about driving a car. (In fact, the moral issues raised by driving a car, both from an environmental and from a safety point of view, are much more serious than those raised by sex.)

The hope of internet anarchists was that repressive governments would have only two options: accept the internet with its limitless possibilities of spreading information, or restrict internet access to the ruling elite and turn your back on the 21st century, as North Korea has done.

Personal purity isn’t really the issue. Not supporting animal abuse – and persuading others not to support it – is.

My fear is that that's what's going to happen with robotics and the military. Importantly, this discussion has to involve not just the scientists, but also the political scientists. It's got to be a multidisciplinary discussion. You can't have it be another repeat of what happened with the people working on the atomic bomb.