If you go back in time you'll find tribes that were essentially only concerned with their own tribal members. If you were a member of another tribe, you could be killed with impunity.

Ancient recipients of instant news probably couldn't do very much about it, for instance. Xerxes would still need three months to get his army together, and he might not get home for years.

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.)

My work is based on the assumption that clarity and consistency in our moral thinking is likely, in the long run, to lead us to hold better views on ethical issues.

When children see animals in a circus, they learn that animals exist for our amusement. Quite apart from the cruelty involved in training and confining these animals, the whole idea that we should enjoy the humiliating spectacle of an elephant or lion made to perform circus tricks shows a lack of respect for the animals as individuals.

Whereas the property-owning middle class could win freedom for themselves on the basis of rights to property--thus excluding others from the freedom they gain--the property-less working class possess nothing but their title as human beings. Thus they can liberate themselves only by liberating all humanity.

Looking back on my career, I think I've been extremely fortunate to be in the right place at the right time in order to have the influence that I did.