In this way the feeling of moral approbation is seen to be the product of time and slow growth of circumstance, a phenomenon to which both reason and sentiment contribute in equal shares in accordance with the laws that condition their development. Moral approbation is no more given instantaneously by sympathy than it is given instantaneously by a moral sense. Sympathy is merely one of the conditions under which it is evolved, one of the feelings which assist in its formation. It is indeed the feeling on which, more than on any other, the moral agencies existing in the world build up and confirm the notions of right and wrong; but it does of itself nothing more than translate feelings from one mind to another, and unless there is a pre-existent moral element in the feeling so translated, the actual passage will not give rise to it. Sympathy enables one man's fear, resentment, or gratitude to become another man's fear, resentment, or gratitude; but the feeling of moral approbation which attends emotions so diffused, arises from reference to ideas otherwise derived than from a purely involuntary sympathyfrom reference, that is, to a standard set up by custom and opinion.
A child told for the first time of a murder might so far enter by sympathy into the resentment of the victim as to feel indignation prompting him to vengeance; but his idea of the murder itself as a wrong and wicked acthis idea of it as a deed morally worse than the slaughter of a sheep by a butcher, would only arise as the result of the various forces of education, availing themselves of the original law of sympathy, by which an act disagreeable to ourselves seems disagreeable in its application to others. And what is true in this case, the extreme form of moral disapprobation, is no less true in all the minor cases, in which approbation or the contrary is felt.
The feeling of moral approbation is therefore much more complex than it is in Adam Smith's theory. Above all things it is one and indivisible, and it is impossible to distinguish our moral judgments of ourselves from our judgments of others. There is an obvious inconsistency in saying that we can only judge of other people's sentiments and actions by reference to our own power to sympathize with them, and yet that we can only judge of our own by reference to the same power in them. The moral standard cannot primarily exist in ourselves, and yet, at the same time, be only derivable from without. If by the hypothesis moral feelings relating to ourselves only exist by prior reference to the feelings of others, how can we at the same time form any moral judgment of the feelings of others by reference to any feelings of our own?