justification, because, where the occurrence of an event did depend upon the will, there, by acting on the will (as we may do by blame or punishment) we have often a reasonable chance of preventing similar events from recurring in the future; whereas, where it did not depend upon the will, we have no such chance. We may, therefore, fairly say that those who speak and think, as if a man who brings about a misfortune voluntarily ought to be treated and regarded in exactly the same way as one who brings about an equally great misfortune involuntarily, are speaking and thinking as if it were not true that we ever should have acted differently, even if we had willed to do so. And that is why it is extremely important to insist on the absolute certainty of the fact that we often really should have acted differently, if we had willed differently.
There is, therefore, much reason to think that when we say that we could have done a thing which we did not do, we often mean merely that we should have done it, if we had chosen. And if so, then it is quite certain that, in this sense, we often really
