Remember that not everyone is as strong as you are. Be mindful of human weakness, and of the fact that it may be more important, in the long run, to get many people taking steps in the right direction than to have fewer achieving the ideal.

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.

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.

Somebody who eats twice as much factory-farmed products as he or she needs to is clearly doing twice as much damage to the planet. From a utilitarian point of view, that's twice as bad.

To be a utilitarian means that you judge actions as right or wrong in accordance with whether they have good consequences. So you try to do what will have the best consequences for all of those affected.

Cheats prosper until there are enough who bear grudges against them to make sure they do not prosper.

History is not going to look kindly on us if we just keep our head in the sand on armed autonomous robotics issue because it sounds too science fiction.