One of the biggest revolutions in my thinking due to critical rationalism (CR) has been in the realm of political philosophy. What political philosophy is implied by CR is somewhat controversial. Popper himself appeared to think that some form of socialism was compatible with CR, while also criticizing utopian conceptions of socialism such as Marx proposed. Many critical rationalists today are proponents of libertarianism, and I count myself among them. I contend that libertarian ideals are an implication of the CR worldview.

Libertarianism can be drawn as a conclusion of the Non-Agression Principle (NAP). The NAP may be stated simply: it is never moral to take aggressive violent action towards other people. Violence is only moral when it is in retaliation or defense.

The idea that ‘taxation is theft,’ a common libertarian catchphrase, can be drawn from the NAP. The NAP implies that taking someone’s property under threat of violence (arrest and imprisonment) without their consent is an agressive action that is neither retaliation nor defense. The NAP also implies that the only crime should be violent crime; enforcing a non-violent crime would itself be violating the NAP by taking aggressive action against the criminal. Crime without a victim does not violate the NAP.

If libertarianism can be derived from the NAP, the only task left is to derive the NAP from CR principles. CR’s claim is that all of our knowledge consists of unjustifiable guesses. Since our knowledge can never be perfect or justified, the only way to further the growth of knowledge is to criticize our current knowledge and attempt to make better guesses.

The most fundamental moral truth is that the means of error correction, criticism, must be protected. This is the most fundamental principle both because moral progress relies on criticism and because the only way we can know that the moral principles we hold are the best that we have access to is by subjecting them to criticism and seeing that they do not fail.

Since none of our guesses can ever be justified, and all of our proposed plans of action are themselves guesses, we can never justify our actions. This is a refutation of utilitarianism as a comprehensive moral system capable of justifying our acts. No moral calculation can justify any particular action, although it may serve as criticism for one. Utilitarians are not wrong to point out that an action that is expected to provide net negative utils (units of pain subtracted from units of pleasure) provides strong incentive not to take that action, but an expected net positive cannot justify an action. For instance, if two actions are both expected to result in the same util value, but one of them violates the NAP, the one that does not violate the NAP should be taken.

Admittedly, the above is a simple case and in the real world things are often more complex. The point is only that moral theories can serve as criticisms, but since an action can never be fully justified, irreversible harms should be avoided. Coercive actions are inherently anti-rational; they prevent error correction by not resolving a disagreement (problem) rationally.

Knowledge grows through conflict within already existing knowledge. When we have an argument with someone, our opponent may find a way to cause us to abandon some theory we previously thought was true. This may occur with all of our practical or scientific theories. It is possible that either or both parties of a conversation are wrong and the only way of discovering this is for both parties to engage in conversation with one another. In order to convince someone else of your position you must be creative; you must find new ways of communicating the idea you have to them so that they will understand what you are saying. It also requires creativity on the part of the person being convinced, otherwise they would not have been able to move to a new position.

Coercion prevents the resolution of a conflict in ideas by arbitrarily favoring one over another. The coercer’s position survives, but because a rational discussion was prevented between the coerced and coercer, it remains unclear whether that position is true or false, or whether the position of the coerced is true or false. Rational discussion and creativity applied to the problem might also have revealed that both positions are flawed and that some other position should be held.

People act on the knowledge they have. One might argue that people often act on intuition or emotion. This is true, but intuition and emotion are themselves forms of knowledge, sometimes knowledge that has developed over millions of years of evolution. Even if we concede for a moment the idea that emotions or intuitions are irrational, they are still affected by relatively intellectual thinking. If you come upon a snake in a field, you may feel intense fear, but this fear will dissipate when you recognize that it is actually just a rope. Your feelings change based on a change in understanding about the facts.

Knowledge often exists independent of any individual person. One type of this kind of knowledge is institutional knowledge. For example, no one person knows how to build a NASA space rocket, but the institution of NASA knows how to build space rockets. Any top-down prohibition or commandment that NASA leadership makes will be at least somewhat coercive in that it will override pre-existing knowledge that has been adapted for making rockets. Unless the institution has a healthy tradition of criticism that allows for pushback against misinformed commands, significant damage can be done in this way. Orders may actually destroy the knowledge needed in order to build rockets.

The economy is essentially an incredibly large computation and store of institutional knowledge that helps individuals know how to allocate resources. No one person knows everything about how the economy works. In a completely free market, no action is coerced. No one can be forced to do a job that they don’t want to and no one is forced to purchase something they don’t want. Knowledge grows or is sustained by these voluntary exchanges by providing information about supply and demand to consumers and business owners. If wages get too low, or prices for goods or services get too high, people will abstain or go elsewhere.

Libertarianism is not itself a solution to all of our problems, or a positive vision of utopia. But it is the best way we know of for organizing a society that is able to solve problems as quickly as possible. It is a system that helps prevent the destruction of the means of error correction by minimizing coercion and maximizing individual freedom to create revolutionary ideas.

See Libertarianism and the Solubility of Problems for more on critical rationalism and libertarianism.