The Rationalist Delusion?

a post hoc investigation

Jeanette Kennett, Philip Gerrans

Research output: Chapter in Book/Report/Conference proceedingChapter


What is a moral judgment? Jonathan Haidt and others who adopt a dual-process model of cognition see moral judgment as largely automatic and regard explicit reasoning as directed to the task of ex post facto justification and persuasion. This chapter argues that a capacity for diachronic agency is essential to moral deliberation and that once we focus on the full range of processes involved in moral decision-making it is not so clear that rationalism is undermined. In particular, initial, quick, affective moral judgments are just one input to moral decision-making, subject to moderation by social and rational pressures consistent with a broadly rationalist perspective.
Original languageEnglish
Title of host publicationMoral Brains
Subtitle of host publicationthe neuroscience of morality
EditorsS. Matthew Liao
Place of PublicationNew York
PublisherOxford University Press
Number of pages13
ISBN (Print)9780199357666
Publication statusPublished - 2016



  • moral reasoning
  • intuition
  • social intuitionist model
  • Jonathan Haidt
  • rationalism
  • dual process
  • moral judgment
  • diachronic agency
  • moral deliberation
  • decision-making

Cite this

Kennett, J., & Gerrans, P. (2016). The Rationalist Delusion? a post hoc investigation. In S. M. Liao (Ed.), Moral Brains: the neuroscience of morality (pp. 74-86). New York: Oxford University Press.