Title

What in the world could show whether moral realism is true?

Date of Completion

January 2006

Keywords

Philosophy

Degree

Ph.D.

Abstract

Philosophers such as Hilary Putnam and Tyler Burge evaluate philosophical positions by testing whether we talk the way that the positions require. In a series of influential papers, Terence Horgan and Mark Timmons follow their lead and construct thought experiments designed to show that we do not talk the way that moral realism requires. In chapter 1, I argue that suitably constructed thought experiments show that we do talk the way that moral realism requires. However, I also question whether the way that we talk is a reliable guide to showing what is real in the world. I distinguish between experiments that test how we talk about the world and experiments that test what happens in the world. In chapter 2, I construct experiments designed to show what would happen in the world under certain conditions if Oxford moral realism were true. In chapter 3, I construct experiments designed to show what would happen in the world under certain conditions if Cornell moral realism were true. In both chapters, I use abductive arguments to interpret the results of the experiments and conclude that moral realism is not true. In chapter 4, I question the role that empirically informed work on human psychology and social relations can serve in establishing moral claims about human lives and social institutions. I identify subtle equivocations between moral and nonmoral conceptions of goodness in work by authors such as Richard Boyd, Martha Nussbaum, and Paul Bloomfield. I elucidate these equivocations by formulating a version of the is-ought gap in which nonmoral goodness takes the role of descriptive premises and moral goodness takes the role of prescriptive conclusions. Moral conclusions about motivation, behavior, and society are underdetermined by many empirically informed premises about nonmoral goodness. ^ In sum, this dissertation defends moral anti-realism in metaethics and sets an agenda for research in substantive ethics that does not founder on mistaken assumptions about metaethics. ^