This paper examines the rhetorical dimension of arguments about global justice. It draws on postcolonial theory, an approach that has explored the relationship between knowledge and power. The global justice literature has elaborated critiques of global inequality and advanced arguments about how to overcome the legacies of domination. These concerns are also shared by critics of colonialism, yet there are also epistemological differences that separate the two scholarly communities. Despite these differences, I argue that bringing the two literatures into conversation generates important benefits. Postcolonial theory draws attention to the way that abstract concepts can function as metaphors that have the unintended consequence of reinforcing power relations. Normative theory will be more effective at promoting global justice if it pays more attention to the politics of representation.