The Fallacy of Ambiguity in the Non-Aggression Principle

The Non-Aggression Principle (NAP) is an effectively axiomatic element of libertarian political philosophy. However, it suffers from a fallacy of ambiguity that results in omitting forms of aggression that are normally accepted as such. The libertarian may argue that this means intuitions of justice must be changed in accordance with this principle, but this is unfounded since it is based on a fallacy of ambiguity. Once the fallacy of ambiguity is identified and clarified, the concept of non-aggression can be refined and extended in a way that eliminates otherwise undesirable and often extreme claims found in libertarian political philosophy.

As a terminological point, there are two uses of the word aggression:  The first is the initiation of hostilities, coercion, or forceful physical action and the second is any hostile, coercive, or forceful physical action. The Non-Aggression Principle is generally accepted as meaning avoiding the initiation of hostile, coercive, or forceful action, but permitting such actions reasonably in self-defense, and such a sense is appropriate.

This concept of non-aggression is distinct from the Indian conception of ahimsa[1] or ‘non-violence,’ popularized by Gandhi who preached non-violence even in self-defense. Ahimsa is essentially the same principle found in Matthew 5:39: “But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also” (King James Bible) and observed in the lives of many saints. The Non-Aggression Principle is quite distinct from this principle for the reason that the Non-Aggression Principle does not forbid hostilities in self-defense.

However, in order to accord with the Non-Aggression Principle, it is essential that self-defense be reasonable in order not to itself constitute an aggression even if the person over-reacting did not initiate the coercion. While this may appear to be a contradiction, this is because each action must be evaluated individually and the initiation of self-defense may constitute the initiation of an aggression if it is excessive. For instance, it is not reasonable for a store owner to shoot a child that steals a piece of candy from his store, but it is reasonable to shoot a person invading one’s home.

This is not to say that self-defense must be proportional. The reason is that action must be evaluated based on the information available at the time of the action, not ex-post information. Very often it is the case that a person knows very little about the aggressor. For instance, in a home invasion, the homeowner generally has no idea who the person is, their true intent, if they are armed, their skill in weapons use or hand-to-hand combat, if there is possibly more than one person, and so on. In such a case, the benefit of the doubt must go to the person being aggressed, so that disproportional defense based on ex-post information is considered reasonable in the judgment of the action of self-defense.

One concern with the Non-Aggression Principle is the ambiguity of what precisely constitutes an aggression and correlatively at what point one is justified in initiating self-defense. It must be recognized that the benefit of the doubt must always be given to the person taking defensive action in order to protect against aggression and judgment is on the action rather than ex-post knowledge of the situation, but this must still fall within the requirement of reasonable self-defense.

This certainly requires judgment and plausible reasoning,[2] but this does not thereby make these judgments “arbitrary,” as some may suggest if the distinction is not based on absolute epistemic objectivity, i.e., deductive logic. If a child steals a pack of chewing gum at a store, it is not “arbitrary” to claim that shooting the child is an unreasonable defense of property and, therefore, constitutes an aggression itself, and it should be clear that deductive logic cannot be the method to judge such action.

One difficulty with this issue is that this objection rests on an erroneous conception of rationality in which there is either absolute epistemic objectivity or else it must, therefore, be epistemically subjective.[3] This is a significant flaw which appears to be common in libertarian thought, and it should be noted that those of the Austrian School of economics should consider that plausible reasoning is at the heart of the subjective theory of value which allows incommensurables to be compared and decided upon utilizing a single intensive scale of value, which is ultimately that of well-being as determined by praxeological analysis.

This process is not arbitrary[4] by any means, and this economic category of choice is the foundation for reasoning, and this foundation of plausible reasoning permits increasingly formalized methods of reasoning to be utilized.[5] This is also realized in Searle’s resolution of the Lewis Carroll Paradox, in which the validity of an inference is not based on further rules but rather independently valid inferences (Searle, 2001: 19-20).[6] In other words, valid inferences are not determined by further rules, but rather are rationally recognized as independently valid.

However, this aspect of reasoning does not mean that one should not strive to maximize epistemic objectivity, which is critical to minimize conflict and improve conflict resolution when it does occur. Epistemic objectivity should be maximized at all times wherever possible, and where it cannot, the role of plausible reasoning must be acknowledged and understood so that it can be properly utilized in judgment.

The error is in over-simplifying the situation in order to attempt to achieve absolute epistemic objectivity or by trying to force the actions of man into a closed logical system of rules in order to attempt to achieve absolute epistemic objectivity, neither of which is rationally tenable. One must always strive to maximize epistemic objectivity, but to take it beyond what is possible in the realm of human action is an egregious error and itself constitutes irrationality.

The fallacy of ambiguity found in the Non-Aggression Principle appears to be the most significant weakness found in contemporary libertarian political philosophy. The problem is not with the principle itself but rather its interpretation. Due to a systemic ambiguity of the terms ‘subjective’ and ‘objective,’ there fails to be a distinction between ontological subjectivity and objectivity on the one hand and epistemic subjectivity and objectivity on the other, along with a failure to distinguish degrees of epistemic objectivity.

Due to the failure to make the former distinction, many libertarian political philosophers often require that the Non-Aggression Principle be interpreted in an ontologically objective manner by requiring physically defined aggression.[7] This results in a profound weakness in the Non-Aggression Principal because this interpretation permits a significant amount of what most people consider an aggression that results in epistemically objective harm.

However, if the Non-Aggression Principle is to be primarily interpreted as requiring epistemic objectivity rather than ontological objectivity in the form of physical acts or physical violations, this widens the purview of what constitutes aggression and permits accommodation of infringements which are otherwise excluded from the conventional libertarian conception of the Non-Aggression Principle.

In cases involving libel or slander, for example, there is no need to require physical aggression in the form of physical ontologically objective harm, contact, or invasion, but instead can be defined in epistemically objective terms of demonstrable damages beyond a reasonable doubt. For instance, if an intentionally false claim results in a person losing his employment, then the time missed from this employment in finding another could be calculated in an entirely epistemically objective manner. It could be easily demonstrated beyond a reasonable doubt in a court of law assuming that one could demonstrate that the employer fired the employee based on the false claim. The damages, although not in any way a physical aggression and the result of a potentially epistemically subjective valuation on the employer’s part, would be classified as aggression and fall within the purview of the Non-Aggression Principle as understood here and, therefore, rights based on epistemically objective evidence. Regardless of the fallacy of ambiguity in the sense of subjective in the subjective theory of value, whether a decision was made based on false information can be demonstrated with epistemic objectivity.

In sum, any interpretation of the Non-Aggression Principle which requires an aggression to be an ontologically objective event and omits epistemically objective acts of aggression is inadequate and a result of the systemic ambiguity of the terms ‘subjective’ and ‘objective’ as well as an inadequate theory of rationality and a failure to distinguish levels of epistemic objectivity. Any act classified as an aggression can be classified as such based on the categories of epistemic objectivity and, therefore, can be demonstrated beyond a reasonable doubt at least in principle.


[1] It is acknowledged that there are different conceptions of ahimsa, for example, the Jain conception is much more extreme and even includes speech, while the traditional Hindu interpretation is not as extreme. There are other conceptions, but this is not the place to make a scholarly distinction of all the different interpretations. Another famous practitioner of ahimsa is Dr. Martin Luther King, Jr. was inspired by Gandhi’s practice of ahimsa, and himself practiced the principle similarly, for example when he was attacked during a speech at the Southern Christian Leadership Conference in Birmingham, Alabama September 28th, 1962 and did not hit back and directed others not to attack the man but instead pray for him  (Alan Deutschman, Walk the Walk: The #1 Rule For Real Leaders, 2009).

[2] Plausible reasoning is an informal method of reasoning which requires judgment rather than logical deduction (Polya, 1954: v). See Hodgson (1991: 114-116) for its use in law and Polya (1954) for its use in mathematics.

[3] There are three levels of epistemic objectivity: Absolute, which is in the realm of math and logic, strong, which is in the realm of the physical sciences, and weak, which is in the realm of sciences like psychology or sociology. With respect to epistemic subjectivity, there is weak epistemic subjectivity that involves plausible reasoning (see footnote 2), and strong epistemic subjectivity, which are matters of pure taste or opinion.

[4]i.e., determined by chance, whim, or impulse, and not by necessity, reason, or principle.

[5] Rothbard has stated that mathematical logic is based upon verbal logic (Rothbard, 1962: 76): “Contrary to what might be believed, the use of verbal logic is not inferior to logistics. On the contrary, the latter is merely an auxiliary device based on the former. For formal logic deals with the necessary and fundamental laws of thought, which must be verbally expressed, and logistics is only a symbolic system that uses this formal verbal logic as its foundation. Therefore, praxeology and economics need not be apologetic in the slightest for the use of verbal logic—the fundamental basis of symbolic logic, and meaningful at each step of the route” (Cf. René Poirier, “Sur Logique” in André Lalande, Vocabulaire technique et critique de la philosophie (Paris: Presses Universitaires de France, 1951), pp. 574–75.).

[6] Full treatment of this issue must be left to future posts. However, suffice it to say that the Classical Theory of Rationality is founded upon the fundamentally mistaken Newtonian Worldview that based on the theoretical structure of Newtonian mechanics that replaces temporal causation with logical necessity. Rather than being understood as a model of the physical world, it was understood to have ontological significance, radically distorting the nature of philosophical explanation for centuries up to the present time of writing. John Searle does not base his philosophy on this Newtonian Worldview, but instead does an excellent job of performing analytic philosophy without these metaphysical distortions common in philosophy. However, an ultimate ontological grounding of his theories is necessary and will also be explained in future posts.

[7] For example, Hans Herman Hoppe (1993: 325): “According to the libertarian ethic, the first such specification is that aggression is defined as an invasion of the physical integrity of other people’s property.” [emphasis in original] Here, too, Hoppe cites Rothbard The Ethics of Liberty (1982) “on the importance of the definition of aggression as physical aggression” in chapters 8 and 9, however, while Rothbard does state that “all legally punishable offenses [are] confined to invasions of the person or property of individuals,” (Rothbard, 1982: 51), other statements are more ambiguous, for example, “In either case, the aggressor imposes his will over the natural property of another—he deprives the other man of his freedom of action and of the full exercise of his self-ownership” (Rothbard, 1982: 45). This is ambiguous for the reason that aggression need not be ontologically objective and that epistemically objective aggressions may deprive a man of freedom of action or self-ownership. This is not to claim, however, that one has a right to property values, as Hoppe explains (Hoppe, 1993: 325, 337).

Works Cited:

Hodgson; David. (1991) The Mind Matters: Consciousness and Choice in a Quantum World. New York, U.S.A.: Oxford University Press  (1993), ISBN: 0-19-824068-6.

Hoppe; Hans Herman. (1993) The Economics and Ethics of Private Property: Studies in Political Economy and Philosophy. Auburn, U.S.A.:  Ludwig von Mises Institute, 2nd edition (2006), ISBN: 978-1-61016-679-9.

Polya; George. (1954) Mathematics and plausible reasoning, Volume 1: Induction and Analogy in Mathematics—a guide to the art of plausible reasoning. Princeton, U.S.A.: Princeton University Press, Eighth Printing (1973), ISBN: 0-691-08005-4.

Rothbard, Murray N. (1962) Man, Economy, and State with Power and Market. Auburn, U.S.A.:  The Ludwig von Mises Institute, Scholar’s Edition (2009) ISBN: 978-1-933550-27-5.

Rothbard; Murray N. (1982) The Ethics of Liberty. New York, U.S.A.: New York University Press (2002) ISBN: 0-8147-7559-4.

Searle; John R. (2001) Rationality in Action. Cambridge, U.S.A.: The MIT Press, ISBN: 0-262-69282-1.