Three different accounts have been given of this principle of approbation. According to some, we approve and disapprove both of our own actions and of those of others, from self-love only, or from some view of their tendency to our own happiness or disadvantage: according to others, reason, the same faculty by which we distinguish between truth and falsehood, enables us to distinguish between what is fit and unfit both in actions and affections: according to others this distinction is altogether the effect of immediate sentiment and feeling, and arises from the satisfaction or disgust with which the view of certain actions or affections inspires us. Self-love, reason, and sentiment, therefore, are the three different sources which have been assigned for the principle of approbation.
Before I proceed to give an account of those different systems, I must observe, that the determination of this second question, though of the greatest importance in speculation, is of none in practice. The question concerning the nature of virtue necessarily has some influence upon our notions of right and wrong in many particular cases. That concerning the principle of approbation can possibly have no such effect. To examine from what contrivance or mechanism within, those different notions or sentiments arise, is a mere matter of philosophical curiosity.
That the tendency of virtue to promote, and of vice to disturb the order of society, when we consider it coolly and philosophically, reflects a very great beauty upon the one, and a very great deformity upon the other, cannot, as I have observed upon a former occasion, be called in question. Human society, when we contemplate it in a certain abstract and philosophical light, appears like a great, an immense machine, whose regular and harmonious movements produce a thousand agreeable effects. As in any other beautiful and noble machine that was the production of human art, whatever tended to render its movements more smooth and easy, would derive a beauty from this effect, and, on the contrary, whatever tended to obstruct them would displease upon that account: so virtue, which is, as it were, the fine polish to the wheels of society, necessarily pleases; while vice, like the vile rust, which makes them jar and grate upon one another, is as necessarily offensive. This account, therefore, of the origin of approbation and disapprobation, so far as it derives them from a regard to the order of society, runs into that principle which gives beauty to utility, and which I have explained upon a former occasion; and it is from thence that this system derives all that appearance of probability which it possesses. When those authors describe the innumerable advantages of a cultivated and social, above a savage and solitary life; when they expatiate upon the necessity of virtue and good order for the maintenance of the one, and demonstrate how infallibly the prevalence of vice and disobedience to the laws tend to bring back the other, the reader is charmed with the novelty and grandeur of those views which they open to him: he sees plainly a new beauty in virtue, and a new deformity in vice, which he had never taken notice of before, and is commonly so delighted with the discovery, that he seldom takes time to reflect, that this political view, having never occurred to him in his life before, cannot possibly be the ground of that approbation and disapprobation with which he has always been accustomed to consider those different qualities.
When those authors, on the other hand, deduce from self-love the interest which we take in the welfare of society, and the esteem which upon that account we bestow upon virtue, they do not mean, that when we in this age applaud the virtue of Cato, and detest the villany of Catiline, our sentiments are influenced by the notion of any benefit we receive from the one, or of any detriment we suffer from the other. It was not because the prosperity or subversion of society, in those remote ages and nations, was apprehended to have any influence upon our happiness or misery in the present times; that according to those philosophers, we esteemed the virtuous, and blamed the disorderly characters. They never imagined that our sentiments were influenced by any benefit or damage which we supposed actually to redound to us, from either; but by that which might have redounded to us, had we lived in those distant ages and countries; or by that which might still redound to us, if in our own times we should meet with characters of the same kind. The idea, in short, which those authors were groping about, but which they were never able to unfold distinctly, was that indirect sympathy which we feel with the gratitude or resentment of those who received the benefit or suffered the damage resulting from such opposite characters: and it was this which they were indistinctly pointing at, when they said, that it was not the thought of what we had gained or suffered which prompted our applause or indignation, but the conception or imagination of what we might gain or suffer if we were to act in society with such associates.
Sympathy, however, cannot, in any sense, be regarded as a selfish principle. When I sympathize with your sorrow or your indignation, it may be pretended, indeed, that my emotion is founded in self-love, because it arises from bringing your case home to myself, from putting myself in your situation, and thence conceiving what I should feel in the like circumstances. But though sympathy is very properly said to arise from an imaginary change of situations with the person principally concerned, yet this imaginary change is not supposed to happen to me in my own person and character, but in that of the person with whom I sympathize. When I condole with you for the loss of your only son, in order to enter into your grief I do not consider what I, a person of such a character and profession, should suffer, if I had a son, and if that son was unfortunately to die: but I consider what I should suffer if I was really you, and I not only change circumstances with you, but I change persons and characters. My grief, therefore, is entirely upon your account, and not in the least upon my own. It is not, therefore, in the least selfish. How can that be regarded as a selfish passion, which does not arise even from the imagination of any thing that has befallen, or that relates to myself, in my own proper person and character, but which is entirely occupied about what relates to you? A man may sympathize with a woman in child-bed; though it is impossible that he should conceive himself as suffering her pains in his own proper person and character. That whole account of human nature, however, which deduces all sentiments and affections from self-love, which has made so much noise in the world, but which, so far as I know, has never yet been fully and distinctly explained, seems to me to have arisen from some confused misapprehension of the system of sympathy.