Moore's Open Question Arguments are among the most influential arguments in 20th Century metaethical thought. But, surprisingly, there is a fair amount of confusion concerning what the Open Question Arguments actually are, how the Moorean passages should be interpreted, and what they are intended to show. Thus, the early chapters are devoted to clarificatory matters, including the exposing of a variety of contemporary attacks upon Moore's arguments as misguided by indicating where they rest upon faulty interpretations of Moorean passages. Providing (...) what I take to be accurate formulations of Moore's famous arguments, responding to historically important preliminary objections, and, finally, presenting various shortcomings of these arguments constitute the remaining themes of the early chapters. ;Next, I pursue an explanation of what I call the 'Open Question phenomenon': the inclination that many have to endorse Moore's "open question" premises. I survey a variety of popular noncognitivist explanations, arguing that each of them is unsatisfactory. I then present a novel semantic explanation of the phenomenon and use it to construct an augmented Moorean Open Question Argument, one capable of overcoming the shortcomings of Moore's originals. ;The latter chapters are dedicated to an investigation of Moore's preferred normative theory---a version of objective consequentialism. I argue that the standard semantic account of subjunctive conditionals fails to capture the nature of certain subjunctive conditionals relevant to the normative evaluation of alternatives from an objective consequentialist perspective. I then present a modified version of the standard account in an effort to remedy the problem. ;Next, I present a novel objection against all extant versions of objective consequentialism. I then introduce and utilize the concept of an "objective" subjunctive probability in the transformation of a subjective version of consequentialism into an objective version, one capable of dealing with the difficulties posed by the objection. ;I conclude the dissertation with a final chapter in which I defend possibilist versions of consequentialism from a contemporary objection. In doing so, I elucidate a theoretical advantage that possibilist theories have over their subjunctive counterparts. (shrink)

§13 of Principia Ethica contains G. E. Moore’s most famous open question arguments. Several of Moore’s contemporaries defended various forms of metaethical nonnaturalism—a doctrine Moore himself endorsed—by appeal to OQAs. Some contemporary cognitivists embrace the force of Moore’s OQAs against metaethical naturalism. And those who posit noncognitivist meaning components of ethical terms have traditionally used OQAs to fuel their own emotivist, prescriptivist, and expressivist metaethical programs. Despite this influence, Moore’s OQAs have been ridiculed in recent decades. Their deployment has been (...) labeled “accident prone,” “simple to dismiss,” and just plain invalid. Critics accuse Moore of begging the question. Others argue that his OQAs founder upon the paradox of analysis. And still others argue that Moore’s open question argumentation is incompatible with the Kripke–Putnam causal theory of reference and thus it “simply fails; it is bankrupt”. I aim to show that there is something of continuing value in Moore’s open question efforts. I present and criticize Nicholas Sturgeon’s influential interpretation of Moore’s OQAs as a means to motivate and explicate my own interpretation of Moore’s thoughts in §13 of Principia Ethica. I then articulate the role that OQAs are intended to play in Moore’s overall argumentative strategies to undermine metaethical naturalism and thereby provide some theoretical support for metaethical nonnaturalism. Finally, I attend to the most prominent objections to Moore’s theorizing and attempt to evaluate the extent to which Moore’s efforts are successful. My hope is to display both the promising portions of Moore’s metaethical argumentation in Principia Ethica as well as its limitations. (shrink)