A Critique of Evolutionary Debunking Arguments in Moral Philosophy

Abstract

Evolutionary debunking arguments (EDAs) have received much attention in recent moral philosophy. These types of arguments draw upon speculative evolutionary premises in order to challenge various philosophical viewpoints and theories. In some cases, empirical evidence has also been used to supplement the more speculative evolutionary premises in debunking arguments. This thesis examines three prominent EDAs, from Sharon Street, Richard Joyce and Joshua Greene. Street’s debunking target is the metaethical position of moral realism, particularly non-naturalistic realism. Joyce’s target is the epistemic justification of moral judgements in general, leading to his conclusion of moral scepticism. Greene targets deontological approaches to moral philosophy, while maintaining that consequentialist theories are unaffected by his debunking claims. The main similarity between these three EDAs is the notion that evolutionary theory can be used to ‘explain away’ certain views in moral philosophy, by providing a scientific explanation of moral views that does not need to assume their truth. The discussed EDAs face some common problems as well as problems specific to each argument. One of the main ways of resisting these arguments is to focus on the human capacity for rational reflection; it will thus be argued that our complex mental capacities enable us to overcome possible evolutionary influences on our moral thinking. This applies not only to the basic level of moral intuitions, but also to the complex moral theories that philosophers develop. It is ultimately concluded that none of the discussed EDAs are successful. However, the possibility of more viable EDAs being developed in the future is not ruled out, provided that they can avoid the criticisms presented against these arguments.