The epistemology of evolutionary debunking

Abstract

The Epistemology of Evolutionary Debunking Justis Koon IntroductionMoral realism, as I will understand it here, is the conjunction of four theses: that moral language should be interpreted literally, that moral claims express beliefs, that there are at least some moral truths, and that these truths are mind-and language-independent. 1 Sharon Street (2006; and Richard Joyce (2006; have both advanced evolutionary debunking arguments which purport to show that, if moral realism is true, our moral beliefs are systematically unjustified. 2 These arguments are motivated by recent empirical work on the evolution of morality, work which suggests that the human moral sense was selected chiefly to promote cooperation among small tribes of huntergatherers in our distant evolutionary past. 3 If, however, our moral sense evolved due to the positive contribution that cooperation made to our ancestors' reproductive fitness, it becomes something of a mystery how it could also succeed in tapping into a well of mind-independent moral truths. It seems like it would be an extraordinary coincidence -in Street's words, nothing short of a miracle -if 1 For comparison, Ayer-style emotivists will reject all four theses, error theorists will reject the third, and moral relativists and constructivists will reject the fourth. There are a few meta-ethical views -I am thinking especially of thin forms of reductive naturalism, like those defended by Copp (2008) and Sterelny and Fraser (2017) -where it is unclear whether we should categorize them as realist or anti-realist. I will not be addressing these sorts of views here. 2 See Horn (2017) and Lutz (2018) for more recent presentations of evolutionary debunking arguments, and Korman ( 2019) for a review of the evolutionary debunking literature. 3 See Section 3.5 and the references therein. 2 evolutionary forces indifferent to the moral truth somehow shaped our faculties to be appropriately sensitive to it.Contrast the situation for vision. Any plausible account of the evolution of our visual faculties will make it clear that they were selected to capture information about the color, shape, texture, brightness, and relative distance of objects in our visual field, and to produce beliefs that accurately reflect these features of our surroundings. 4 We should not expect natural selection to have made our vision perfectly reliable, of course, both because selection is not all-powerful and must work within existing physical and biological constraints, and because visual illusions may, in rare circumstances, be adaptive. But, generally speaking, it will be an enormous boon to an organism's fitness for it to have an accurate picture of its environment, rather than being left in the dark about what goes on around it, blind not only to the presence of food, water, and potential mates, but also to the threats posed by predators and other hazards. So evolutionary theory gives us every reason to think that our visual faculties were selected primarily to produce true beliefs about the sources of the lig...

Recalibrating evolutionary debunking

“…This way of formalizing the argument is adapted fromKoon (2021).8 Similarly, we should understand phrases like "our capacity for moral cognition" as referring to whatever cognitive faculty or faculties are responsible for producing our moral intuitions, judgments, and beliefs, when those faculties are applied to the moral domain.9 CompareMachery & Mallon (2010) on this point.10 Christensen (2010) gives a nice overview of higher-order evidence.…”