Non-Aggression Principle

The non-aggression principle is an ethical principle forbidding the use of aggression – initial physical force, the threat thereof (coercion), or fraud. It's directly derived from the natural right to self-ownership. Combined with the homestead principle, it forms the basis of libertarianism.

Murray N. Rothbard believed that the non-aggression principle was necessary to prevent contradictions of the right to self-ownership.

The non-aggression principle (NAP} based in the theory of natural right and in the context of property rights does not particularly forbid protection or justice, but instead manages to allow justifiable protection against aggression and justice in relation to the restitution of damages. According to Rothbard, if a person uses aggression, reason would dictate that in order to avoid contradiction, a contract must be assumed in which the aggressor owes the victim something as great, but no greater than, that which he or she was deprived.

Aggression, like all blanket terms, is made up of several different variations. The NAP, however, does not always apply to this somewhat ambiguous topic. In a Rothbardian sense, aggression is composited of two variations, that is fraud and violent invasion of property.

Aggression doesn't apply to inaction such as the refusal to help somebody in need, or the use of one's own property as leverage. It also doesn't apply to something a person does to his or her self, because their right to self-ownership isn't being violated in such cases. Likewise, the broad term of “harm” is often either omitted by libertarian philosophers or replaced with a one of the two variations of aggression. In the libertarian sense, harm itself does not always mean aggression, but rather only physical aggression or breach of contract implies a violation of the NAP.

According to Rothbard,

[If] A is a successful seller of razor blades. But then B comes along and sells a better blade, teflon-coated to prevent shaving cuts. The value of A's property is greatly affected. Should he be able to collect damages from B, or, better yet, to enjoin B's sale of a better blade? The correct answer is not that consumers would be hurt if they were forced to buy the inferior blade, although that is surely the case. Rather, no one has the right to legally prevent or retaliate against “harms” to his property unless it is an act of physical invasion. Everyone has the right to have the physical integrity of his property inviolate; no one has the right to protect the value of his property, for that value is purely the reflection of what people are willing to pay for it. That willingness solely depends on how they decide to use their money. No one can have a right to someone else's money, unless that other person had previously contracted to transfer it to him.

In the law of torts, “harm” is generally treated as physical invasion of person or property. The outlawing of defamation (libel and slander) has always been a glaring anomaly in tort law. Words and opinions are not physical invasions. Analogous to the loss of property value from a better product or a shift in consumer demand, no one has a property right in his “reputation.” Reputation is strictly a function of the subjective opinions of other minds, and they have the absolute right to their own opinions whatever they may be.

In cases of fraud, a contract was made between two or more parties, and one or more of them violated it. Therefore, defrauder can't expect to have legitimate ownership of what the contract would have allowed them. For example, if Bob buys cake from Steve, but doesn't pay as previously agreed, the property is assumed to still belong to Steve.

The most widely acknowledged form of aggression includes the use of violent, physical force to obtain, threaten, or hurt another individual. A common example would be if Bob punched Steve in the face in order to hurt him without permission or justifiable reason to do so.

It is important to note that though this example may vary significantly in details, the core concept of aggression rests on the innocence of Steve and the guilt of Bob in a Rothbardian context. In the libertarian framework, it matters not if Steve had taunted Bob because the action of taunting is not a violent invasion of Bob's property, whereas the punching of Steve is.