Principles and acts

A universality test is a test of principles, and yet is supposed to help us select acts. If principles and acts were in one–one or one–many correspondence, there would be no problem. We could simply test a principle, and if it turned out that it was morally acceptable (or, more specifically, morally obligatory or morally worthy, etc.), then we would know that any act falling under it would have the same moral status. Unfortunately this is not the case. Not only can a given principle be acted on repeatedly and in various ways, but any given act exemplifies numerous principles. Just as principles and instantiations of principles are in many–many correspondence, so are principles and acts. Of any act and of any agent an indefinitely large number of descriptions is true. So any act is covered by all those principles incorporating at least one true act description and at least one true agent description.

Only if all the principles which cover an act meet the condition specified by a universality test, or if all of them fail to meet it, can that test of principles be action-guiding. Only in this unusual case would a necessary condition on morally acceptable principles be a necessary condition on an act, or a decision procedure for some species of morally acceptable principles provide one for that sort of morally acceptable act. So if conditions on principles are to be action-guiding, except in this one case, we must specify some way of deciding which of the principles covering an act it is relevant to assess in a given context. We must find some method for deciding what the relevant descriptions of a given agent and act are. Let us call the problem of finding a method by which to select two such descriptions and in doing so to arrive at a single relevant composite act description, the problem of relevant descriptions. This is a problem which cannot be avoided by any theory which proposes a condition on principles and claims to be action-guiding. Indeed, it is widely perceived as a crucial problem for which a solution must be provided.