This paper examines the contribution of The Theory of Moral Sentiments to the study of how we acquire moral knowledge. In Smith, this is associated with the moral judgment of an impartial spectator, a hypothetical ideal conjured in the imagination of an agent. This imagined spectator has the properties of impartiality, information and sympathy. I argue Smith develops this construct in the context of personal ethics, i.e., as a guide to moral conduct in personal relationships. There are limitations, however, to this model for personal ethics, as acknowledged by Smith himself and suggested by subsequent social science findings. Moreover, this model does not necessarily extend to social ethics, i.e., to moral judgment in less personal economic and social interactions, such as firms, industries and governments. Hence, I propose modifying the spectator model in light of modern social science methods and of Smith’s own insights to address its limitations for personal ethics and to provide it with a foundation for social ethics. The proposed approach is based on a quasi-spectator, i.e., the empirical analysis of the moral views of real spectators whose properties approximate those of the ideal spectator. A review of quasi-spectator studies suggests this as a promising method for informing both descriptive and prescriptive ethics.
