The Righteous Mind

Jonathan Haidt's 2012 argument that moral reasoning is post-hoc rationalization of intuitive moral judgment (the elephant and the rider) and that liberals and conservatives use different moral foundations — providing the psychological account of political polarization.

Creates Moral Foundations Theory and explains political polarization psychologically — Haidt's argument that conservatives use all six moral foundations (care, fairness, loyalty, authority, sanctity, liberty) while liberals primarily use two (care and fairness) explains why liberal arguments often fail to persuade conservatives.