If we all think only of our own interests, we are headed for collective disaster - just look at what we are doing to our planet's climate.

I don't think nationalism is alone holding the field; it's in contention with a lot of different things.

Whatever the reason, for most of the present century, the literature and publicity of the old established [animal welfare] groups made a significant contribution to the prevailing attitude that dogs and cats and wild animals need protection, but other animals do not. Thus people came to think of "animal welfare" as something for kindly ladies who are dotty about cats, and not as a cause founded on basic principles of justice and morality.

Of all the arguments against voluntary euthanasia, the most influential is the slippery slope: once we allow doctors to kill patients, we will not be able to limit the killing to those who want to die.

I believe that nationalism is a very strong force, but there are other forces operating; there are tendencies pushing towards a larger picture, especially in Europe, I think; but I still think nationalism is real.

If it is in our power to prevent something bad from happening, without thereby sacrificing anything of comparable moral importance, we ought, morally, to do it.

Why...is the hunter who shoots a deer for venison subject to more criticism than the person who buys a ham at the supermarket? Overall, it is probably the intensively reared pig who has suffered more.