Abstract
Morality is a pervasive characteristic of human societies, with social norms and codes of conduct defining acceptable and unacceptable behaviors across cultures. Our evolved moral sense facilitates group living by regulating interpersonal interactions and promoting cooperation beyond the bounds of kinship ties. Moral beliefs that are held with high certainty and perceived as absolute and universally applicable can motivate a strong commitment to justice and benevolent collective action. They also have a darker side. Moral conviction can foster dogmatism, intolerance, and punitive actions, including vigilantism and violence. This article integrates theories and empirical evidence from evolutionary social psychology, cognitive science, political psychology, and neuroscience to examine both the ultimate and proximate mechanisms of moral conviction. This interdisciplinary approach clarifies the functional architecture and potential deleterious consequences of moral conviction.