… is from page 136 of GMU Econ alum Edward Stringham’s important 2015 Oxford University Press book, Private Governance :
The most personal form of private governance is individual self-governance or internal moral constraints. Ignored by strict neoclassical economists, the importance of individual self-governance or internal moral constraints has been discussed by writers from Adam Smith to Immanuel Kant and Leo Tolstoy. Internal moral constraints are rules that people choose to follow even if other people do not impose them; these constraints are chosen from within. Manners, politeness, honesty, and trustworthiness are common examples of internal constraints that people commonly adopt independent of external rules.