Problems for Moral Twin Earth Arguments*

Terry Horgan and Mark Timmons have recently presented a series of papers in which they argue against what has come to be called the ‘new wave’ moral realism and moral semantics of David Brink, Richard Boyd, Peter Railton, and a number of other philosophers. The central idea behind Horgan and Timmons’s criticism of these ‘new wave’ theories has been extended by Sean Holland to include the sort of realism that drops out of response-dependent accounts that make use of an analogy between moral properties and secondary qualities. This paper argues that Holland’s extension depends crucially on the fact that his target is a direct response-dependent account of moral value. His argument does not work against such accounts of more basic normative notions such as ‘harm’ or ‘benefit’. And these more basic notions may then serve as the basic normative building blocks for an indirectly response-dependent moral theory. * Thanks to Mark Timmons for helpful and friendly comments on an earlier version of this paper, and also to an audience at the 2003 Pacific APA, and to the reviewers for this journal.