This paper has two central aims. The first is to explore philosophical complications that arise when we move from (i) explaining the evolutionary origins of genetically influenced traits associated with human cooperation and altruism, to (ii) explaining present manifestations of human thought, feeling and behaviour involving cooperation and altruism. While the former need only appeal to causal factors accessible to scientific inquiry, the latter must engage also with a distinctive form of explanation, i.e. reason-giving explanation, which in turn raises important philosophical questions, the answers to which will affect the nature of the ultimate explanations of our moral beliefs and related actions. On one possibility I will explore, this explanatory project cannot avoid engaging with first-order ethical theory. The second aim is to apply lessons from these explanatory complications to the critique of ‘evolutionary debunking arguments’, which seek to debunk morality, or at least objective construals of it (i.e. moral realism), by appeal to allegedly scientific debunking explanations of our moral beliefs that would defeat our justification for them. The explanatory complications brought out in the first half raise difficulties for such debunking arguments. If we avoid begging central philosophical questions then such debunking arguments pose little threat of saddling us with moral scepticism or subjectivism, though they do pose an important challenge for those developing a moral realist view.
A New Evolutionary Debunking Argument Against Moral Realism
