"The libertarian seeks property assignment rules because he values or accepts various grundnorms such as justice, peace, prosperity, cooperation, conflict-avoidance, and civilization. The libertarian view is that self-ownership is the only property assignment rule compatible with these grundorms; it is implied by them.”
-  “Grundnorm” was legal philosopher Hans Kelsen’s term for the hypothetical basic norm or rule that serves as the basis or ultimate source for the legitimacy of a legal system. See Hans Kelsen, General Theory of Law and State, trans. Anders Wedberg (Cambridge, Mass.: Harvard University Press, 1949). I employ this term to refer to the fundamental norms presupposed by civilized people, e.g., in argumentative discourse, which in turn imply libertarian norms.
That the libertarian grundnorms are, in fact, necessarily presupposed by all civilized people to the extent they are civilized — during argumentative justification, that is — is shown by Hoppe in his argumentation-ethics defense of libertarian rights.
For discussion of why people (to one extent or the other) do value these underlying norms, see Stephan Kinsella, “The Division of Labor as the Source of Grundnorms and Rights,” Mises Economics Blog (April 24, 2009), and idem, “Empathy and the Source of Rights,” Mises Economics Blog (Sept. 6, 2006). See also idem, “Punishment and Proportionality,” pp. 51 and 70:
- People who are civilized are … concerned about justifying punishment. They want to punish, but they also want to know that such punishment is justified — they want to legitimately be able to punish … Theories of punishment are concerned with justifying punishment, with offering decent men who are reluctant to act immorally a reason why they may punish others. This is useful, of course, for offering moral men guidance and assurance that they may properly deal with those who seek to harm them.
— Stephan Kinsella