To a certain extent this conception of Nature, and recognition of design, entered into the general thought of the time. Even Hume said, "It is wisely ordained by nature that private connexions should commonly prevail over universal views and considerations; otherwise our affections and actions would be dissipated and lost for want of a proper limited object." But Adam Smith more particularly adopted this view of things, and the assumption of Final Causes as explanatory of moral phenomena is one of the most striking features in his philosophy; nor does he ever weary of identifying the actual facts or results of morality with the actual intention of nature. It seems as if the shadow of Mandeville had rested over his pen, and that he often wrote rather as the advocate of a system of nature which he believed to have been falsely impugned than as merely the analyst of our moral sentiments.
Writing too as he describes himself to have done, with an immense landscape of lawns and woods and mountains before his window, it is perhaps not surprising, that his observation of the physical world should have pleasantly affected his contemplation of the moral one, and blessed him with that optimistic and genial view of things, which forms so agreeable a feature in his Theory .
The extent to which Adam Smith applies his doctrine of final causes in ethics is so remarkable, that it is worth while to notice the most striking examples of it.
Our propensity to sympathize with joy being, as has been said, much stronger than our propensity to sympathize with sorrow, we more fully sympathize with our friends in their joys than in their sorrows. It is a fact, that however conscious we may be of the justice of another's lamentation, and however much we may reproach ourselves for our want of sensibility, our sympathy with the afflictions of our friends generally vanishes when we leave their presence. Such is the fact, the final cause of which is thus stated: "Nature, it seems, when she loaded us with our own sorrows, thought that they were enough, and therefore did not command us to take any further share in those of others than was necessary to prompt us to relieve them."Another purpose of nature may be traced in the fact, that as expressions of kindness and gratitude attract our sympathy, those of hatred and resentment repel it. The hoarse discord- ant voice of anger inspires us naturally with fear and aversion, and the symptoms of the disagreeable affections never excite, but often disturb, our sympathy. For, man having been formed for society, "it was, it seems, the intention of nature that those rougher and more unamiable emotions which drive men from one another should be less easily and more rarely communicated."Our natural tendency to sympathize with the resentment of another has also its purpose. For instance, in the case of a murder, we feel for the murdered man the same resentment which he would feel, were he conscious himself, and into which we so far enter as to carry it out as his avengers;and thus, with regard to the most dreadful of all crimes, has nature, antecedent to all reflections on the utility of punishment, stamped indelibly on the human heart an immediate and instinctive approbation of the sacred and necessary law of retaliation.
Resentment within moderation is defensible as one of the original passions of our nature, and is the counterpart of gratitude. Nature "does not seem to have dealt so unkindly with us as to have endowed us with any principle which is wholly and in every respect evil." The very existence of society depending as it does on the punishment of unprovoked malice, man has not been left to his own reason, to discover that the punishment of bad actions is the proper means to pre- serve society, but he has been endowed with an immediate and instinctive approbation of that very application of punishment which is so necessary. In this case, as in so many others, the economy of nature is the same, in endowing mankind with an instinctive desire for the means necessary for the attainment of one of her favourite ends. As the self-preservation of the individual is an end, for which man has not been left to the exercise of his own reason to find out the means, but has been impelled to the means themselves, namely, food and drink, by the immediate instincts of hunger and thirst, so the preservation of society is an end, to the means to which man is directly impelled by an instinctive desire for the punishment of bad actions.