  The heterogeneity of matter in Holbach’s metaphysics puts him at a disadvantage to the traditional Lockean view, in a sense. Locke’s account of matter, if true, is simpler and has great explanatory power: the full panoply of sensations that we encounter are to be explained by an account of our sensory organs, a short list of primary qualities, and the laws which govern their interaction. Holbach, on the other hand, requires separate explanations for each perceived property. He promises an explanation of all phenomena in terms of matter and motion, but delivers not even a framework for such an explanation.