Adam Smith is seen as the great defender of self-interest, but in his Theory of Moral Sentiments, he develops a theory of behavior founded on the individual’s capacity to switch roles with others. Against the utilitarianism of conventional economic theory, Smith holds that man derives satisfaction not only from his own pleasure but also from sympathetic involvement in the experiences of his fellow-beings. For Smith, even the self-seeking, materialistic behavior necessary to energize the capitalist system stems in the last resort from fellow feeling. Since Smith remained faithful to this socialpsychological viewpoint throughout his life, the Wealth of Nations needs to be reinterpreted in the light of the Theory of Moral Sentiments.