A critical appraisal of the Dual Process account of moral judgment

The Dual Process account asserts that moral judgments are the result of a competition between two independent decision processes: a utilitarian process and a deontological/affective process. We trace the development of the dual process account and highlight how the neural and behavioral evidence almost universally relies on the validity of a series of untested statements that, collectively, we call the Dual Process assumption. We show how the acceptance of this assumption produces experimental methods that cannot falsify the dual process account. By way of contrast, we highlight a competing account of moral reasoning, Psychological Value Theory (PVT), which is embodied in a computational model that supports very detailed and falsifiable predictions. PVT is based on a radically different set of assumptions to those of the dual process account. Such assumptions accord well with generally accepted processes of stochastic decision-making. PVT’s predictions have been verified and provide strong evidence that the Dual Process assumption is invalid. We recommend reassessing the conclusions of research that relies on the Dual Process assumption.