The Non-Aggression Principle

One of the more common bedrock concepts in libertarian ideologies that seems to at least be present, lurking in the mental background, regardless of how heavily emphasized (or not) it is. The concept is somewhat familiar to anyone with a basic understanding of liberal theories of rights. For example, "Your right to swing your fist ends at my nose." The idea is that we may exercise our rights to the extent that we do not interfere with others' exercise of their rights. This is theory of negative rights, and libertarianism takes it in a more technically abstract and vague direction.

The non-aggression principle (hereafter NAP) stipulates that it is absolutely morally impermissible to initiate the use of force or its credible threat (i.e., "aggress") against another person. In the implied gap, we have the right to do anything which does not count as aggressing against someone else. This is one of those classically "sounds good in theory" concepts. We can accept readily that committing acts of violence or threatening to do so is bad except in some rare circumstances, such as self-defense (which is not *initiating* force). But how far can we take this principle?

## In Their Own Words

The Mises Institute, on their own wiki, defines this principle as follows:

The **non-aggression principle** (also called the **non-aggression axiom**, or the **anti-coercion** or **zero aggression principle** or **non-initiation of force**) is an ethical stance which asserts that "aggression" is inherently illegitimate. "Aggression" is defined as the "initiation" of physical force against persons or property, the threat of such, or fraud upon persons or their property. In contrast to pacifism, the non-aggression principle does not preclude violent self-defense. The principle is a deontological (or rule-based) ethical stance.
Already we can see that the implications of this go a bit beyond what might seem obvious from the basic principle: why is "fraud" an instance of aggression anyway? This and other questions are the major subject of this page.

The Mises Wiki has a number of quotations on this principle which go back farther than actual modern libertarian thinkers, establishing the basic idea of the NAP as having a long lineage. It is not clear, though, that everyone who espoused the basics of this principle saw it as an absolute in the way that libertarians do. For example, if Thomas Jefferson said that "No man has a natural right to commit aggression on the equal rights of another, and this is all from which the laws ought to restrain him," is this compatible with slavery, a thing he seemed to not be in a rush to oppose? (The surprising answer: Maybe!)

## The NAP and Rights

The NAP establishes a basis for a theory of negative rights - i.e., "freedom from" interference - but perhaps more important is the fact that it delegitimizes any theory of positive rights - i.e., an enabled "freedom to" - as a violation of its own terms. Positive rights to be able to do things, after all, require some enabling entity which, if it truly guarantees something as a right, would almost certainly be funded by taxes, which are inherently an initiation of force. Not all libertarians will take this to the limit of its implications and call for the complete abolition of the state in any form, recognizing the nearly obvious fact that in order for any negative right to be guaranteed as a right, a set of "protecting" institutions analogous to "enabling" institutions will be necessary.

But how does it actually function as a basis for rights? By allowing you to do anything that does not violate it. What counts as a violation? "Aggression," but as seen above, aggression is not really a transparent concept.

Consider this thought experiment: someone has claimed several thousand acres of forest as his personal property and posted signs along the borders of this plot of land. He does not actually use most of this land. He'll hunt on it periodically but he lives alone and can't practically visit all of it on any day. Suppose that, near to sundown, a hiker is trying to reach a campground on the opposite side of this private stretch of land. He sees the "No Trespassing" signs, and realizes that he might end up in the forest at night and lost if he tries to circumvent it. So instead he sets off through it, resolving to not touch or harm anything but to simply walk straight to the other side as quickly as possible. In the middle of the traverse from one side to another, he comes across the owner, who informs him that he's trespassing on private property and will have to got back the way he came. The hiker apologizes and explains that he just needs to get to the other side before nightfall. The owner refuses to allow this, seeing no reason to help a trespasser and demands that the hiker go back the way he came or else the owner will protect his rights by whatever means available... which would certainly include the hunting rifle he's carrying. Even lacking that, though, he would press charges against the hiker in a court of law.

Question: who is aggressing in this scenario? The obvious libertarian answer is, in fact, the hiker. The owner is simply defending his property rights from the hiker's aggressive violation of them. But how did he come to have a right to this huge expanse of forest? The homesteading theory and principle of just transfers would say that his rights derived from peaceful acquisition, either by the original appropriation of simply claiming that land or by purchasing it from a legitimate owner. In other words, the right to this title comes from a set of actions establishing ownership in accordance with the NAP.

There is a problem here, though: this is circular reasoning. The hiker is violating the NAP by infringing in the owner's rights to property, but these property rights are based in the NAP. In other words:

1. We know what our rights are: whatever we do that does not aggress against another, we have a right to do.
2. We know what constitutes aggression: whatever violates another's rights is aggression.

Either the definition of aggression assumes what it is supposed to establish, the scope of our rights, or the theory of rights derived from the NAP assumes what it is supposed to establish, what rights we have which can be violated. It effectively tells us nothing worthwhile about what our rights are because it has no definition of aggression independent of its own implications.