Abstract
that the properties of science are purely extrinsic with the metaphysical principle that substances must also have intrinsic properties, the arguments reach the conclusion that there are intrinsic properties of whose natures we cannot know. It is the goal of this paper to establish that such arguments are not just ironic but extremely problematic. The optimistic physicalist principles that help get the argument off the ground ultimately undermine any justification the premises give for acceptance of the conclusion. Though I do find these arguments unsound, it is nevertheless worthwhile to consider them in order to see more clearly what should be the methodology of the philosopher inclined to take the discoveries of physical science as having ontological authority. And, I hope, what follows will prompt the physicalist to ask herself – what room _is_ there for metaphysics once physical science is complete?