Habits of thought lead us to brush aside descriptions of cruelty to animals as emotional, for "animal-lovers only"; or if not that, then anyway the problem is so trivial in comparison to the problems of human beings that no sensible person could give it time and attention. This too is a prejudice - for how can one know that a problem is trivial until one has taken the time to examine its extent?

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.

If penicillin had been judged by its toxicity to guinea pigs, it might never have been used by man.

There is an obvious evolutionary explanation for the scarcity of altruistic saints: Without a strong predilection for their own interests, our ancestors would have been unlikely to survive, reproduce, and give their own offspring a chance of doing the same. Now conditions have changed and for most of us, surviving and reproducing isn't such a struggle but we still carry the genes of our ancestors and they influence - not determine, but influence - our behavior.

Egoism... is not eliminated by economic reorganization or by material abundance. When basic needs are satisfied, new 'needs' emerge. In our society, people want no simply clothes, but fashionable clothes; not shelter, but a house to display their wealth and taste.

I'm a Utilitarian, so I don't see the rule against lying as absolute; it's always subject to some overriding utility which may prevent its exercise.

So why don't we make ourselves the last generation on earth? If we would all agree to have ourselves sterilized then no sacrifices would be required - we could party our way into extinction!