If we're going to live an ethical life, it's not enough just to follow the thou-shalt-nots. … If we have enough, we have to share some of that with people who have so little.

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.

Forests and meat animals compete for the same land. The prodigious appetite of the affluent nations for meat means that agribusiness can pay more than those who want to preserve or restore the forest. We are, quite literally, gambling with the future of our planet – for the sake of hamburgers

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.

It is easy for us to criticize the prejudices of our grandfathers, from which our fathers freed themselves. It is more difficult to distance ourselves from our own views, so that we can dispassionately search for prejudices among the beliefs and values we hold

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.

The belief that the animals exist because God created them - and that he created them so we can better meet our needs - is contrary to our scientific understanding of evolution and, of course, to the fossil record, which shows the existence of non-human primates and other animals millions of years before there were any human beings at all.