Abstract

One of the most persuasive arguments against moral realism is the argument from disagreement. It argues that the best explanation for the vast amount of disagreement in ethics is that there are no moral facts. For this argument to work two points must be established. First, inference to the best explanation must be a justified rule of inference, and second, the "no moral facts thesis" must be shown to be the best explanation of moral disagreement. I provide justification for the first, but argue against the second. The first task is a difficult one. Some, such as Richard Fumerton, have argued that inference to the best explanation is simply a type of induction lacking any independence as a form of inference, and Bas van Fraassen has argued that inference to the best explanation is an irrational rule of belief revision. Using Gilbert Harman as a guide, I argue Fumerton has things backwards: induction requires IBE. Similarly, van Fraassen misunderstands IBE while inadvertently using it himself Inference to the best explanation nevertheless does fall victim to the criticism that it begs the question, if a priori justification cannot be found. Hence, after giving an analysis of explanation that requires reference to the cause or nature of the event to be explained, I provide an a priori defense of the criteria of inference to the best explanation that while limited does provide some justification. The best explanation is likely to be true. Finally, I argue that the second point the anti-realist must make is miscalculated. The best explanation of moral disagreement is a realist position based on intuitively justified pluralistic moral criteria similar to W. D. Ross's prima facie duties. Due to the plurality of criteria, and the lack of a system to determine which criteria are overriding when there is conflict, we can easily explain the disagreement. The theory is also strengthened because it is able to explain the agreement that exists when there is no conflict among the criteria