Its purity, or the chance it has of not being followed by sensations of the opposite kind: that is, pains, if it be a pleasure: pleasures, if it be a pain. These two last, however, are in strictness scarcely to be deemed properties of the pleasure or the pain itself; they are not, therefore, in strictness to be taken into the account of the value of that pleasure or that pain. They are in strictness to be deemed properties only of the act, or other event, by which such pleasure or pain has been produced; and accordingly are only to be taken into the account of the tendency of such act or such event."