 Although physics does not seem to challenge these two theses, several philosophers do challenge them on distinctively philosophical grounds. Some of them suggest that the nomic, the intensional, or the normative do not supervene on the distribution of perfectly natural properties. Others suggest that the nomic,  intentional,  or normative properties are perfectly natural, and as a consequence perfectly natural properties are not freely recombinable. The philosophical arguments in favour of such positions rarely turn on the precise constitution of the Humean’s preferred subvenient base. If Lewis can show that such arguments fail in the setting of classical physics, then he’ll have refuted all of the arguments against Humean superveience that don’t rely on the details of modern physics. In practice that means he’ll have refuted many, though not quite all, of the objections to Humean supervenience.