The proposition in argumentation ethics is that “arguing for any political position other than libertarian anarchism is logically inconsistent” (wiki).  This proposition was set forth in 1988 by Professor Hans-Hermann Hoppe of the University of Nevada at Las Vegas. The basic idea is that the non-aggression principle is a premise implied in every argument, and so it cannot be logically denied in any doctrine. The concept of argumentation or discourse ethics had been developed by several German philosophers, such as Jürgen Habermas.

The non-aggression principle is that aggression – the initiation of force or fraud against a person –  is morally evil. The argumentation proposition is that non-aggression is a presupposition of every argument, and so the concept cannot be logically denied within an argument. If a person argues that slavery is justified, the contradiction is that by engaging in argument with another person, he is implying that they are both seeking to arrive at truth by persuasion as equal independent non-slave parties. Since the person who argues for slavery is not using force to make the other person a slave, that implies that he is thereby rejecting slavery. It is then logically and performatively inconsistent for him to argue that enslaving any other person would be justified.

The prevailing argument for a libertarian ethic, based on natural moral law, is based on human nature applied to human action, rather than argumentation. The two premises set forth by John Locke in his Second Treatise of Government are human independence and equality.

Independence is the biological statement that persons think and feel as independent beings. Equality means that human beings have an equal moral worth, which is the basis of Jefferson’s statement that we are created equal, and is the basis of equality before the law. The equality premise is based on the observation that there is no inherent master-slave relation among human beings, and so equality is more consistent with human biology than any inherent moral superiority of any race, sex, or culture.

Hoppe states that concept of human nature is too diffuse to provide a determinate set of premises for natural law. Locke’s premises of independence and equality indeed have fuzzy edges, such as for beings not yet born, but they seem to be clear enough for practical purposes. Libertarians have no consensus on issues such as abortion, capital punishment, land value subsidies, the use of the military, and the justification of imposed government, but argumentation does not resolve such issues either. One needs additional premises to solve issues such as personhood, e.g. under which conditions is a human organism a person with rights. After all, one cannot have discourse with a newly born baby.

The concept of argumentation ethics has been rejected by several libertarian scholars, for example the article in The Journal of Libertarian Studies (Spring 2006) by Robert Murphy and Gene Callahan. They point out that at most, argumention establishes self-ownership only to one’s mind and mouth, and only during the argument. A slave owner can argue with a slave while the slave is in chains, and then murder the slave. The superiority of the slave owner is not refuted by the owner’s asking the slave whether he prefers to be strangled or shot with a bullet.

As pointed out by Murphy and Callahan, a statist may believe that under particular conditions, the initiation of force is justified, even though when this is discussed, the parties are equally in their ability to argue.

Another refutation was made by Jason Brennan in “Hoppe’s Argumentation Ethics Argument Refuted in Under 60 Seconds.” Brennan first presents two definitions. “A liberty right is something that grants me permission to do something. A claim right is something that entails others have obligations, responsibilities, or duties toward me.”

He then writes:

“all I need to avoid a performative contradiction here is for me to have a liberty right to say, ‘I propose such and such.’ I need not presuppose I have a claim right to say ‘I propose such and such.’ Instead, at most, I presuppose that it’s permissible for me to say, ‘I propose such and such’. I also at most presuppose that you have a liberty right to believe what I say. I do not need to presuppose that you have a claim right to believe what I say. However, libertarian self-ownership theory consists of claim rights… Hoppe’s argument illicitly conflates a liberty right with a claim right, and so fails.”

Yet another refutation of argumentation is made in “Justopia” by Justin:

“That flaw is revealed by showing that intent matters. This flaw eliminates the performative contradiction aspect because one cannot, without further information, determine whether many of the statements that Hoppe would claim are performative contradictions actually are performative contradictions.”

The Lockean foundation for natural moral law does not suffer from such flaws. Based on its premises from human nature, the universal ethic has three basic rules:

1. Acts which are welcomed benefits are good.
2. All acts, and only those acts, which coercively harm others are evil.
3. All other acts are neutral.

It is curious why some natural-law libertarians have not accepted Locke’s libertarian ethic and have instead turned to German discourse philosophy. Perhaps the answer involves psychology and sociology rather than pure philosophy. At any rate, argumentation ethics is not the answer.

(This article also appears in http://www.progress.org )