Writing in an age that exalted reason, the Scottish-born skeptic David Hume was the first modern philosopher to emphasize the role of psychology, or 'passion', in the formulation of moral judgments and ethical systems. Included in this edition of his ethical writings is the entire text of An Enquiry Concerning the Principles of Morals, selections from A Treatise of Human Nature and Dialogues Concerning Natural Religion, and the essays 'Of the Original Contract', 'Of the Standard of Taste', and 'Of Suicide'. Professor MacIntyre's introduction clarifies the relationship of Hume's intellect to his Calvinist background and cogently summarizes his importance to the subsequent development of moral philosophy.