 P. Kyle Stanford (1998), on the other hand, distinguishes real essences from internal constitutions by arguing that real essences, by definition, include the causal powers of the body, whereas the internal constitution is simply its material components. Thus, for Stanford, a real essence “consists of those features of an entity from which all of its observable or experienceable properties can be logically deduced” (Stanford 1998, p. 80). By contrast, knowledge of the internal constitution, qua mere material components, entails no such deducibility. For example, in IV.vi.11 he says that knowledge of the real essence of an object entails knowledge of all of its powers, but knowledge of mere material structure cannot entail that kind of knowledge. Moreover, in all the quotations where Locke talks about real essences, he does not just define them as a material structure, but also as the causal grounds of the observable qualities of the body, indicating that the powers are included in the definition.