Should one break in and free the animals? That is illegal, but the obligation to obey the law is not absolute. It was justifiably broken by those who helped runaway slaves in the American South, to mention only one possible parallel.

My aim is to advocate that we make this mental switch in respect of our attitudes and practices towards a very large group of beings: members of species other than our own - or, as we popularly though misleadingly call them, animals. In other words, I am urging that we extend to other species the basic principle of equality that most of us recognize should be extended to all members of our own species.

We don't usually think of what we eat as a matter of ethics. Stealing, lying, hurting people - these acts are obviously relevant to our moral character. In ancient Greece and Rome, ethical choices about food were considered at least as significant as ethical choices about sex.

Sci-fi is often a metaphor. I think it's more the themes and questions that science fiction raises rather than the exact predictions that should guide us.

Had Rumsfeld said at any time 'get me a report on what's going on', he could have had it. You're right, it depends on choices that we make, which parts of the world we want to be in immediate contact with.

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

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.