ABSTRACT
The question I wish to discuss in this chapter is: when two individuals, or two groups, differ as to what is desirable, are there any means, and if so what, of showing that one party is in the right? To avoid arousing active partisan feeling, let us take some dead issue, for example slavery. For a long time slavery was accepted without question; then there was a controversy lasting about a hundred years; then it was decided that the world was better without slavery. If we put ourselves back, in imagination, into the period of controversy, what has ethics to say as to how we ought to have made up our minds?
