Non-aggression principle

The non-aggression principle (NAP), also called the non-aggression axiom, is the fundamental principle of morality that states that any person is permitted do everything with his property except aggression, defined as the initiation of forceful action, which is in turn defined as 'the application or threat of' 'physical interference (property breach) or fraud (contract breach)', any of which without consent. The principle is also called the non-initiation of force. The principle incorporates universal enforcability.

The non-aggression principle is considered by some to be an essential idea of libertarianism, voluntaryism, anarcho-capitalism or minarchism.