The Moral Animal

Wright presents evolutionary psychology for a general reader, using Darwin's own life as a running case study to show how the theory explains behaviour that Darwin himself displayed without understanding.

The substantive content covers parental investment theory and its predictions about mating behaviour, the different reproductive strategies available to each sex and the resulting conflicts, kin selection and Hamilton's rule explaining altruism toward relatives, reciprocal altruism and the conditions under which cooperation between unrelated individuals is stable, status competition, and the argument that moral sentiments including guilt, gratitude, indignation and affection are mechanisms evolved to make reciprocal exchange work.

His most consequential argument concerns self-deception. Wright holds that the conscious mind functions substantially as a public relations department, constructing justifications for behaviour whose actual causes are inaccessible, and that this is adaptive because a person who genuinely believes their own case argues it more convincingly. This anticipates the argument Simler and Hanson made later in The Elephant in the Brain. The Darwin biography running through the book shows Darwin's own status anxiety, his treatment of Wallace, his family relationships and his Victorian moral positions, all analysed through the framework.

Evolutionary psychology has been substantially contested since 1994, on the grounds that its hypotheses are difficult to falsify, that the cross-cultural evidence is weaker than claimed, and that it has been used to naturalise existing arrangements. Wright is careful to state that explanation is not justification, which readers frequently ignore. The self-deception argument is the part with the most durable support.