In Search of Greene's Argument

The moral psychologist Joshua Greene has proposed a number of arguments for the normative significance of empirical research and for the unreliability of deontological intuitions. For these arguments, much hinges on the combination of various components of Greene's research – namely the dual-process theory of moral judgement, ‘personalness’ as a factor in moral decision-making, and his functional understanding of deontology and consequentialism. Incorporating these components, I reconstruct three distinct arguments and show that the Personalness Argument for the claim that empirical research can advance normative ethics and the Combined Argument against deontology are both sound and interesting in themselves. They do not, however, cast doubt on traditional deontology or reserve a specific role for neuroscience. The Indirect Route argument overcomes some of the other arguments’ limitations. It is, however, invalid. I conclude by pointing out the broader philosophical relevance of Greene's arguments as shedding light on second-order morality.