We have to distinguish between different classes of conditions under which disinterested retributive emotions arise. In the first place, we may feel disinterested resentment, or disinterested retributive kindly emotion, on account of an injury inflicted, or a benefit conferred, upon another person with whose pain, or pleasure, we sympathise, and in whose welfare we take a kindly interest. Our retributive emotions are, of course, always reactions against pain, or pleasure, felt by ourselves; this holds true for the moral emotions as well as for revenge and gratitude. The question to be answered, then, is, Why should we, quite disinterestedly, feel pain calling forth indignation because our neighbour is hurt, and pleasure calling forth approval because he is benefited? {109} That a certain act causes pleasure or pain to the by-stander is partly due to the close association which exists between these feelings and their outward expressions. The sight of a happy face tends to produce some degree of pleasure in him who sees it; the sight of the bodily signs of suffering tends to produce a feeling of pain. In either case the feeling of the spectator is the result of a process of reproduction, the perception of the physical manifestation of the feeling recalling the feeling itself on account of the established association between them. Sympathetic pain or pleasure may also be the result of an association between cause and effect, between the cognition of a certain act or situation and the feeling generally produced by this act or situation. A blow may cause pain to the spectator before he has witnessed its effect on the victim. The sympathetic feeling is of course stronger when both kinds of association concur in producing it, than when it is the result of only one. As Adam Smith observes, "general lamentations which express nothing but the anguish of the sufferer, create rather a curiosity to inquire into his situation, along with some disposition to sympathise with him, than any actual sympathy that is very sensible."[1] On the other hand, the sympathy which springs from an association between cause and effect is much enhanced by the perception of outward signs of pleasure or pain in the individual with whom we sympathise. [Footnote 1: Adam Smith, _Theory of Moral Sentiments_, p. 7.]