Non-descriptive definitions are part of the reason for the failure of libertarianism. With descriptive definitions rather than vague obscurantist “principles” the philosophical vacuousness of the movement is readily exposed.
The reason these debates still occur, and the reason this article is just one of thousands of similar pretentions is the fact that the NAP is untestable. And as I have argued, it is untestable for the same reason that dialectical materialism is untestable: to allow for individual interpretation of scope of that which can be aggressed upon. And therefore, via suggestion, creates a false consensus on the complete sentence where there is none. Nearly all libertarian differences are reducible to differences in the definition of property that can be aggressed upon: physical, externality, normative, institutional, territorial.
The NAP sounds meaningful to many but because as an incomplete sentence, it leaves the object of aggression substitutable by each individual. AS SUCH NAP IS MORALLY RELATIVE since each person interprets the scope to which aggression must be limited differently.
Yet, to form a voluntary polity, one cannot posses moral relativity. The problem with any such polity is (a) whether it competes as a rational choice of membership versus competing polities (especially given high transaction costs in anarchy) and (b) whether it is possible to sustain competition for power from within such a polity, and (c) whether such a polity would be tolerated by neighboring polities.
The NAP is just another bit of verbal deception like dialectical materialism or the labor theory of value. It’s another bit of pseudoscientific nonsense. one does not determine that which is “right” – others do. One determines what is right by whether or not others retaliate against you for it.
Walter Bock and Murray Rothbard’s ancestors practiced the NAP in the wildlands and ghettos of Eastern Europe, and were almost always exterminated or outcast for it. And it is probably the reason why the polity was never able to functionally produce the commons that were necessary for the defense of and holding of territory.
The jewish method of argument originating in their scriptures is indirection, suggestion, and externality. The entire methodology of monotheistic abrahamic religion is deception by suggestion using half truths, loading, overloading and repetition. (Gossiping). The methods of marx, freud, boaz, cantor, mises, rothbard are all examples of this kind of deceit. They give us half truths consisting of comforting lies, that we desperately wish to believe, and through heaping of undue praise, the parchment, pulpit, book, magazine, newspaper, radio, television, play and movie they distribute a desirable falsehood in order to obscure the unpleasant truth. Lies are much cheaper than truths and more desirable. So in every era that new means of distributing lies at a discount was made possible by technology, thy have created new methods of lying and distributed them vociferously.
The only liberty that is existentially possible is that which prohibits retaliation, because it is the need for costly retaliation that causes demand for the authoritarian state to suppress retaliation. The only cure is to provide an institutional means for resolving any and all cases of retaliation, so that there is no existentially possible demand for the state that is not in and of itself a demand for parasitism.
Period. End of story. Individual moral choice is a lie. Morality is empirically determined by the value of cooperation and the cost of retaliation.
But it is a cognitive bias, probably born of developmental defect that causes people to become attracted to libertarianism in order to claim to determine morality on their own, of their own choice, rather than out of necessity. And why? Because as outcasts the desire to escape payment for normative and physical commons is a rational reaction to obtaining less value from the commons than one is required to pay in costs.