Putting the Critical-Rationalism in Libertarianism
Libertarianism is the ideology that liberty should be observed first as a social rule. As the content of my other posts are variations on this theme, not much need appear in this entry. However, it ought to be noted briefly that this definition is a version of, if not identical with, classical liberalism. So it is about the protection of persons and their non-aggressively acquired property allowing for maximal free markets and minimal state control.
One interesting assumption is that libertarianism is necessarily a moral position. Surely it almost always is. However, it would be consistent to advocate it for, for instance, non-moral narrowly self-interested reasons (as anyone is more likely to thrive if liberty is generally respected) or even misanthropic reasons (but here the advocate must consider the results a disaster for most people).
Many, probably most, libertarians think they need some form of justification, foundation or support for their ideology. Various attempts include basing it on autonomy, contractarianism, natural law, utilitarianism or some other form of consequentialism, and, of course, empirical evidence. Although one can subscribe to, or simply use, any of these to defend, or criticize, libertarianism without also being a justificationist.
There is an explicit non-justificationist alternative: critical-rationalist libertarianism. If someone asks a critical-rationalist libertarian to justify his views, he would probably decline to attempt this as he thinks it impossible. He does not adhere to libertarianism on any basis whatsoever. Like all theories, it is ultimately a mere conjecture. All one can do with a conjecture is test it with empirical evidence and intellectual criticism; both of which must also involve conjectures that themselves always remain open to testing. Thus the only reasonable policy is to look for the best tests or criticisms available.
If it comes to convincing a critic, this can only mean answering his specific criticisms as far as possible. Even if this were eventually done to the satisfaction of the critic, it remains just as much an unjustified conjecture as before. It simply wastes time to attempt a futile justification when one will have to answer the specific criticisms of all comers anyway; yet one can also usefully think up criticisms for oneself and attempt to answer them.