Hume's Law: An Essay on Moral Reasoning (review)

Hume Studies Volume 31, Number 1, April 2005, pp. 177-180 HAKAN SALWEN. Hume's Law: An Essay on Moral Reasoning. Stockholm: Almqvist & Wiksell International, 2003. Pp. 154. ISBN 91-22-02044-6, paper, $62.50. Much has been written about Hume's infamous statement that an "ought" cannot be derived from an "is," leading many readers to wonder whether there is anything new to say about it. Salwén's discussion of "Hume's Law" shows that not only is there something new to say about the topic, but also that there is much more work to be done on it. His stated purpose is "to assess the tenability and significance of Hume's law" (10) by exploring the different ways it can be interpreted and the implications each interpretation has for broader issues in meta-ethics, epistemology, and the philosophy of language. Readers oÃ- Hume Studies will notice that nowhere in this stated purpose is an attempt to analyze Hume's own position, and Salwén makes no pretenses about doing so. He dutifully quotes Hume's is/ought passage in the introduction and moves very quickly to a discussion of contemporary interpretations of Hume's law, which constitute his primary focus. This is thus not a book on Hume. It is, however, a detailed and technical analysis and defense of Hume's law. While I do not think his project succeeds, many parts of his discussion are worthwhile. In addition to giving very concise summaries of many different positions people have taken on the debate surrounding Hume's law, Salwén raises a number of important issues concerning the connection between Hume's law and various epistemological positions. Of particular interest is his approach to defending Hume's law: while most people tend to accept or reject Hume's law on its own, and then explore the implications of this acceptance or rejection for their other philosophical commitments , Salwén looks first to our prior commitments in logic, meta-ethics, epistemology, and philosophy of language, and then uses these commitments to determine the truth of Hume's law. His discussion of these issues—while at times problematic - stand to give the reader new insight into the question of how moral claims are related to non-moral ones, even if Salwén's own answer to this question is unsatisfactory. Salwén takes as his starting point Brink's formulation of Hume's law: "Moral claims cannot be inferred from non-moral claims" (10). From here, he gives three different, and, I think, previously underappreciated, interpretations of the sort of inference implied by Hume's law. The first is a formalized interpretation, labeled HL(F). HL(F) is the claim that "a moral expression (no matter what expression counts as moral) cannot occur non-vacuously in the conclusion of a valid inference unless it appears among the premises" (17). The second is a conceptual interpretation , labeled HL(C). HL(C) is the claim that "there is no analytic bridge premise" Hume Studies 178 Book Reviews that connects non-moral premises, such as "Jones has promised to pay Smith five dollars" to moral conclusions, suchas "Jones ought to pay Smith five dollars" (18). The third interpretation is the epistemological interpretation, labeled HL(E). HL(E) is the claim that "A non-moral belief constitutes an epistemic reason for a person, P, at a certain time, t, to hold an atomic moral belief only if P at t accepts a moral principle connecting the two beliefs" (76). Of these three interpretations, HL(F) receives the least amount of discussion, as, for reasons not entirely clear, the bulk of the text devoted to this interpretation is relegated to the Appendix. In his Chapter One introduction to HL(F), Salwén discusses Pigden's proof, and concludes that, on conservative interpretations of logic, HL(F) is true. He goes on to discuss the implications of HL(F), and claims that it is neutral with respect to either cognitivism and non-cognitivism, and does not imply that naturalism is false. These implications, Salwén argues, goes against what most people take to be the central implications of Hume's law, namely, that non...