Abstract
For a long time Hume's philosophical achievement was judged almost entirely by Book I of the Treatise . A major contribution of Kemp Smith's work on Hume was the insistence that the epistemological doctrines of Book I were essentially related to the ethical theory of Book III. Recent moral philosophy has found Book III to be of considerable intrinsic interest and relevance to current problems. It is now becoming apparent, however, that Hume's ethical theory is intimately bound up with the philosophy of mind in Book II. This new emphasis upon the significance of Book II for Hume's ethics derives from Dr Pall S. Árdal's book Passion and Value in Hume's Treatise . In view of Árdal's influence on continuing study in this field—witness the recent book by Philip Mercer—it becomes important to point out what I take to be a major error in one part of Árdal's analysis of the relationship between Hume's philosophy of mind and his moral theory