Adam and eve: A thought experiment

To simplify the relation between desire and morality, and between personal and moral good, we can imagine a world of only two people; let us call them Adam and Eve, for the sake of tradition. This gives us two types of personal good: good for Adam and good for Eve. What is good for Adam (or Eve) is what tends to realise his or her desires in general, and, where desires conflict, realises the desires that are stronger in the long-term. A benevolent and omniscient observer - let's call him Snake out of perversity - could therefore draw up two plans of action, one which is good for Adam and one which is good for Eve. However, at this point, Snake must choose sides, since obviously these goods are not always compatible. It is here that Snake must evolve into a moral being, since he must find a way to choose between good-for-Adam and good-for-Eve in order to produce a general good (even though we have not really decided what the general good might involve yet).