"We must recognize that only scarce resources are ownable; second, that the body is a type of scarce resource; third, that the mode of acquiring title to external objects is different from the basis of ownership of one's own body."

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The basis of self-ownership is the fact that each person has direct control over the scarce resource of his body and therefore has a better claim to it than any third party (and any third party seeking to dispute my self-ownership must presuppose the principle of self-ownership in the first place since he is acting as a self-owner).

— Stephan Kinsella