The Psychology of Moral Reasoning

In the last issue of Judgment and Decision-Making (Volume 3, Number 2, February 2008),

Monica Bucciarelli, Sangeet Khemlani, and P. N. Johnson-Laird (well-known for his research on mental models in reasoning) present an account of the psychology of moral reasoning (pdf - html). It is based on many experiments and gives a large place to deontic reasoning (often neglected in current moral psychology) and constrasts sharply with many sentimentalist accounts of morality (according to which moral judgment is mainly emotional). Their main findings are :

1. Indefinability of moral propositions: No simple criterion exists to tell from a proposition alone whether or not it concerns morals as opposed to some other deontic matter, such as a convention, a game, or good manners.
2. Independent systems: Emotions and deontic evaluations are based on independent systems operating in parallel.
3. Deontic reasoning: all deontic evaluations, including those concerning morality, depend on inferences, either unconscious intuitions or conscious reasoning.
4. Moral inconsistency: the beliefs that are the basis of moral intuitions and conscious moral reasoning are neither complete nor consistent.