Old Wine in New Bottles

Abstract

Evolutionary debunking arguments (EDAs) purport to show that robust moral realism, the metaethical view that there are non-natural and mind-independent moral properties and facts that we can know about, is incompatible with evolutionary explanations of morality. One of the most prominent evolutionary debunking arguments is advanced by Sharon Street, who argues that if moral realism were true, then objective moral knowledge is unlikely because realist moral properties are evolutionary irrelevant and moral beliefs about those properties would not be selected for. However, no evolutionary, causal explanation plays an essential role in reaching the argument's epistemological conclusion. Street's argument depends on the BenacerrafField challenge, which is the challenge to explain the reliability of our moral beliefs about causally inert moral properties. The Benacerraf-Field challenge relies on metaphysically necessary facts about realist moral properties, rather than on contingent Darwinian facts about the origin of our moral beliefs. Attempting to include an essential causal empirical premise yet avoiding recourse to the Benacerraf-Field problem yields an argument that is either self-defeating or of limited scope. Ultimately, evolutionary, causal explanations of our moral beliefs and their consequences do not present the strongest case against robust moral realism. Rather, the question is whether knowledge of casually-inert, mind-intendent properties is plausible at all.

Can Moral Realists Deflect Defeat Due to Evolutionary Explanations of Morality?

“…However, it stands to reason that the defeating power of the reliability challenge does not depend on evolutionary causal considerations per se (cf. Klenk, 2017), in which case the defeating power of the reliability challenge seems relevantly similar to the defeating power of the cognition-disrupting pills discussed by Moon. For reasons of space, I cannot engage further in this debate in this article.…”

“…Moreover, there are good reasons to conceive of the reliability challenge as an a priori challenge, and in this case, it is even clearer that it does not arise at a particular moment in time (cf. Klenk, 2017).…”

What can debunking do for us (sceptics and nihilists)?

“…3 Justin Clarke-Doane has argued in a series of papers that debunking arguments against moral non-naturalism are analogous to the Benacerraf challenge to Platonism about mathematics (see, e.g., Clarke-Doane, 2016). Similarly, Michael Klenk has argued that Street's evolutionary debunking argument against moral realism relies crucially on the so-called Benacerraf-Field challenge, applied to moral knowledge (Klenk, 2017).…”

Evolutionary arguments against moral realism: Why the empirical details matter (and which ones do)

“…(Street 2006, p. 155)If not as an evolutionary challenge, how should Street’s EDA be understood? Several commentators (Enoch 2010; Clarke-Doane 2012; Crow 2016; Klenk 2017; Tersman 2017; Schechter 2018) have interpreted her argument as the moral analogue of the Benacerraf-Field challenge for mathematical Platonism. Roughly, in its generalized form, this is the challenge of explaining how we can reliably track facts or truths about some specified domain, if we assume that these facts or truths are stance-independent and causally inert.…”