I don't see how anyone could really think that if you have a choice between saving the life of one person and saving the lives of a million people, to say - well, I've saved the one - can you really take that seriously? I can't.

But I think the majority of cows, and even more so chickens and pigs, are leading pretty miserable lives.

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.)

Of those who die from avoidable, poverty-related causes, nearly 10 million, according to UNICEF, are children under five. They die from diseases such as measles, diarrhoea, and malaria that are easy and inexpensive to treat or prevent.

We wait until Pandora's box is opened before we say, "Wow, maybe we should understand what's in that box." This is the story of humans on every problem.

All the particular moral judgments we intuitively make are likely to derive from discarded religious systems, from warped views of sex and bodily functions, or from customs necessary for the survival of the group in social and economic circumstances that now lie in the distant past.

There are a lot of weapons that we've developed which we've pulled back from - biological weapons, chemical weapons, etc. This may be the case with armed autonomous robotics, where we ultimately pull back from them.