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.

I know of a number of people who are successfully earning to give. That isn't for everyone but for those with the ability to earn a lot of money and the character to resist the temptation to spend it on themselves, it can be a great way to do good.

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.

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.

The statement "I am in pain" may be one piece of evidence for the conclusion that the speaker is in pain, but it is not the only possible evidence, and since people sometimes tell lies, not even the best possible evidence. Even if there were stronger grounds for refusing to attribute pain to those who do not have language, the consequences of this refusal might lead us to reject the conclusion. Human infants and young children are unable to use language. Are we to deny that a year-old child can suffer?

If you have the abilities to earn a lot of money and if you have the character to persist in giving that to the most effective charities you can find, then that may be the best thing that you can do. And - also, if you do become a Wall Street banker, I think you need to be aware of what you're doing in terms of your daily work, not just earning money to give a lot away. But you need to think about - am I harming people through the work that I'm doing?

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.