It is a fact that 2 + 2 = 4. It is a fact that bears can swim. It is a fact that many people believe that it is morally wrong to steal. There are many types of facts—mathematical, biological, and psychological, to name a few. The question I set out to answer in this thesis is: Are there any moral facts? It is a fact that many people believe it is morally wrong to steal, but is it also a fact that it is morally wrong to steal? I examine three arguments against the possibility of moral facts and one supporting argument. One of the skeptical arguments comes from Gilbert Harman and two come from J. L. Mackie. The supporting argument comes from Michael Smith. I argue that not one of these arguments succeeds. I then present my own positive argument, which is similar to arguments from other moral realists in that it is an argument to the effect that morality is based on rationality, and conclude that there are moral facts.
The first skeptical argument, from Harman, is this: If there were any moral facts, then they would have to figure in the best explanations of our experiences; but moral “facts” do not figure in the best explanations of our experiences, so there are no moral facts. I argue that this argument is unsound because the second premise is false—moral facts do indeed help explain some of our experiences.
The second skeptical argument, from Mackie, is this: If there were any moral facts, then they would have to be intrinsically motivating; but no facts are intrinsically motivating, so there are no moral facts. I argue that this argument is unsound because the first premise is false; I maintain that it is common but not necessary for the judgment that a moral fact obtains to motivate an agent, and that this is so even if the agent is practically rational. Smith gives an argument which, if successful, would support this premise that I reject. His argument is this: If moral facts were not intrinsically motivating, then the very best that a moral agent could be, conceptually, would be fetishistic; but the very best that a moral agent can be, conceptually, is not fetishistic, so moral facts, if there are any, must be intrinsically motivating. Against Smith, I argue that moral facts could be extrinsically motivating and this would not rule out the conceptual possibility of a truly good moral agent.
The third skeptical argument, from Mackie, is this: If there were any moral facts, then they would necessarily provide reasons for action; but no facts necessarily provide reasons for action, so there are no moral facts. I argue that this argument is unsound because there are facts that necessarily provide reasons for action and so moral facts, if there are any, could be facts of this type.
The positive argument I offer for thinking that there are moral facts is this: All persons are the same in that each has desires she or he wants satisfied, so if one wants one of these persons’ desires satisfied (e.g. one’s own), then one must equally want all of these persons’ desires satisfied, because all persons are the same in this respect. I claim that such impartial treatment of persons with respect to desire satisfaction is at least partially constitutive of morality, so if we have reason to act impartially then we have reason to act morally; and if we have reason to act morally, then there are moral facts.