every such action, our theory says, it is true that it cannot at any time have been both right and wrong; and also that, whichever of these two predicates it possessed at any one time, it must possess the same at all times. But it does not imply that the same is true of any particular class of actions—of murder, for instance. It does not assert that if one murder, committed at one time, was wrong, then any other murder, committed at the same time, must also have been wrong; nor that if one murder, committed at one time, is wrong, any other murder committed at any other time must be wrong. On the contrary, though it does not directly imply that this is false, yet it does imply that it is unlikely that any particular class of actions will absolutely always be right or absolutely always wrong. For, it holds, as we have seen, that the question whether an action is right or wrong depends upon its effects; and the question what effects an action will produce depends, of course, not only upon the class to which it belongs, but also on the particular circumstances in which it is done. While, in one set of circumstances, a particu-
