  Second, if Locke indeed identifies material bodies’ real essences with the primary qualities of their constituent corpuscles, then that view of real essence, together with his pessimism about the possibility of ever discovering real essences, implies pessimism about the corpuscular hypothesis—specifically, about the claims that bodies are made of corpuscles and that their observable qualities are reducible to the corpuscles’ qualities. In the same passages in which Locke seems to accept or assume these central tenets of the corpuscular hypothesis—that observable bodies are made up of corpuscles and that those corpuscles have a restricted set of inherent properties—he simultaneously appears very skeptical about the hypothesis’ promise to reduce observable properties such as color and taste to that restricted set of primary properties.