A Defense of Mackie's Moral Error Theory: Essays on the Argument from Queerness and Formulation Problems



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In Ethics: Inventing Right and Wrong, J. L. Mackie argues that, while our moral claims point “to something objectively prescriptive,” no such things exist and thus “these claims are all false” (Mackie 1977). A number of issues with Mackie's articulation of “moral error theory” have cast doubt on the view. This work defends two essential claims of moral error theory: the claim that moral facts would be queer, and that all moral claims would be false. In response to the claim that moral facts would be queer, several eminent philosophers have developed metaphysical accounts of moral facts that apparently avoid any queerness (Nagel 1997, Putnam 2004, Parfit 2011, Scanlon 2014). According to them, moral facts exist without ontological robustness, so they would not be queer. However, once the argument from queerness is more clearly articulated, it becomes apparent that the queerness of moral facts is not that they are ontologically robust, but that they are additional fundamental ontological commitments. Thus, even if facts can exist non-robustly, moral facts are queer. It has also been suggested that the central thesis of moral error theory that “all moral claims are false” may entail a contradiction (Sinnott-Armstrong 2006, Pigden 2010, Olson 2014). There are two separate problems that could both lead to a contradiction. The first problem can be solved by formulating the central thesis of error theory as “All positive moral claims are false” and the second problem can be solved by redefining the deontic definition of permissibility as the following: an action is permissible if and only if that action is not wrong and there is some action that is wrong.



J. L. Mackie, moral error theory, argument from queerness, quietist normative realism, formulation problems