Political realism (henceforth realism) maintains that political philosophy should source its basic substantive claims about politics from a distinct, autonomous, and authoritative “political” normative domain. The most plausible realist account of the distinctiveness, autonomy, and authority of the political domain is the practice-based account, which tells us to use the norms inherent to real-world statist social practices as a basis for anchoring and demarcating it. I develop three objections to the practice-based account. First, the practice-based account generates inconsistencies in sets of substantive principles presumed to be true, which realism lacks the theoretical resources to resolve. Second, the practice-based account fails to establish the distinctiveness of the political domain because statist social practices and substantive claims about these practices implicate persons. Finally, the practice-based account fails to secure the autonomy and authority of the political domain because social practices must be justified against practice-independent considerations.
