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.

The problem is not with the athletes, but with us. No matter how blatant the drug use may be, we don't stop watching the Tour de France. Maybe we should just turn off the television and get on our own bikes.

As for cages themselves, an ordinary citizen who kept dogs in similar conditions for their entire lives would risk prosecution for cruelty. A pig producer who keeps an animal of comparable intelligence in this manner, however, is more likely to be rewarded with a tax concession or, in some countries, a direct government subsidy.

We see things like reciprocity which are fairly central to our view of ethics. But if you're talking about a set of worked-out rules on what we are supposed to do then, yes, it is a human product.

Whereas the property-owning middle class could win freedom for themselves on the basis of rights to property--thus excluding others from the freedom they gain--the property-less working class possess nothing but their title as human beings. Thus they can liberate themselves only by liberating all humanity.

It is a mistake to assume that the law should always enforce morality.

To give preference to the life of a being simply because that being is a member of our species would put us in the same position as racists who give preference to those who are members of their race.