Scholars of justice theory often refuse to apply their principles to concrete social or political issues; instead, they develop those principles in abstraction from contemporary value conflicts or policy debates, preferring to remain silent on how justice might inform controversial political decisions. Rawls, for example, casts questions concerning the application of his “justice as fairness” conception across national, generational, and species boundaries as among the several “problems of extension” for which his theory may or may not be equipped, noting that “the idea of political justice does not cover everything, nor should we expect it to” (1993, 20–21). Even where he applies his justice theory to problems of international relations in his The Law of Peoples, Rawls describes its application as merely “an extension of a liberal conception of justice for a domestic regime to a Society of Peoples” (1999, 9), as though constructing and applying justice principles are entirely discrete steps, with its application to concrete social or political issues a unidirectional project of wielding static principles as practical tools, offering nothing of importance to a normative theory's development.