Before I talk about morality, I want to talk about the values that all of us share.  On this slide are those things that everyone regards as harms or evils; death, pain, disability, loss of freedom, and loss of pleasure, and those things that everyone regards as goods or benefits, consciousness, ability, freedom, and pleasure. I expect that all of you will agree with the list of harms and benefits. If you are doing a cost-benefit analysis, you will not have any doubt about what belongs on the cost side and what on the benefit side. However, there is considerable variation in the ranking of these harms and benefits. Except for death, all of the other harms can be more or less severe, and even death is ranked differently at different ages, so there is no ranking of the harms such that everyone agrees that one kind of harm is worse than another. Further, even when the severity of the harms involved is specified, rational people still disagree about which of the harms is worse. There is no unique rational ranking of the harms or of the benefits, and the controversy is about which of two harms is worse, or which of two benefits are better, or whether gaining a given good compensates for suffering a given harm. But all of this disagreement is compatible with complete agreement about what is a harm and what is a benefit.