Master of Arts (MA)


Philosophy and Religious Studies

Document Type



In the late twentieth century, moral realists began to resurrect a type of argument that emerged during the Enlightenment. These realists appealed to moral progress as evidence for moral facts, and their arguments took the form of inferences to the best explanation. Recently, the argument style has emerged again. This time, the inference to the best explanation is being used by empirically-informed sentimentalists to argue that their theories can provide accounts of moral evolution that have greater explanatory and predictive power than the accounts offered by the moral realists. This thesis examines the arguments to the best explanation of such moral realists as Nicholas Sturgeon, Michael Slote, Michael Smith, Peter Singer, and Thomas Nagel. The views of these moral realists are confronted with the substantial empirical evidence provided by Shaun Nichols to bolster his Sentimental Rules account, which is a variety of sentimentalism. Nichols attempts to expand epidemiological approaches to cognitive anthropology to accommodate his research on affect-backed norms. I elucidate Nichols’ research and his own inference to the best explanation of the data he examines as well as his attack on the accounts provided by the moral realists. After examining this substantive piece of the debate over what actually counts as the best explanation of moral evolution, I argue that the inference to the best explanation is actually being employed in two distinct uses by these theorists. The first use presupposes a metaethical thesis regarding the nature of moral facts and renders the inference circular. The majority of the moral realists examined employ the inference in this fashion. The second use is not circular, but leaves the theorist with a very restricted ability to fill out the content of moral beliefs and moral facts.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Gregory J. Schufreider