Page:Ethics (Moore 1912).djvu/21

 pain, the total quantity of pleasure should be greater than the total quantity of pain. These are two out of the six theoretically possible cases; and these two may be grouped together by saying that, in both of them, the action in question causes an excess of pleasure over pain, or more pleasure than pain. This description will, of course, if taken quite strictly, apply only to the second of the two; since an action which causes no pain whatever cannot strictly be said to cause more pleasure than pain. But it is convenient to have some description, which may be understood to cover both cases; and if we describe no pain at all as a zero quantity of pain, then obviously we may say that an action which causes some pleasure and no pain, does cause a greater quantity of pleasure than of pain, since any positive quantity is greater than zero. I propose, therefore, for the sake of convenience, to speak of both these first two cases as cases in which an action causes an excess of pleasure over pain.

But obviously two other cases, which are also theoretically possible, are (1) that in