Scarcity is a universal, unknowable, marginal indifference. It is praxeologicaly non-existent. I cannot know and act on it. Cost is particular, knowable, and decidable because of marginal differences. It is praxeologicaly existential. I can know and act on it.
Scarcity is a necessary constraint between states, that need not reduce local transaction costs, but which must avoid conflict despite differences in in-group (local) rules.
Morality is important between individuals, because they must reduce transaction costs sufficiently to engage in production in a division of knowledge and labor. Morality prohibits free riding, and is determined by costs that are knowable by the actors.
Polities must form laws (rules) of cooperation, that mix the necessary rules of morality (prohibition on free riding), with the rules necessary for the production of commons, with the utilitarian allocation of privileges (norms) that assist in either parasitism or the organization of production or both.
Rothbard, as a cosmopolitan, was trying to justify separatism. Not describe necessary properties of cooperation, nor the necessary properties of rule of law, under which a group of people can cooperate without allocation of discretion to individuals with authority.
( That basic argument should put the bullet in Hoppe’s Scarcity argument forever. Just like I have put the bullet in his Argumentation forever. Just like I have put a bullet in ghetto ethics forever. Just like I have put a bullet in the NAP(IVP) forever. Just as I suspect I may have put a bullet in ‘meaning’ forever. )
The Propertarian Institute