Truth is said to be what corresponds to reality. If this is so, then truth must be one thing, and reality another. Metaphysics, as I understand it, is an enquiry into the nature of this supposed reality. Presumably, such an enquiry, if it is possible at all, must start with whatever knowledge of the world we think we have, and consider what implications it may have concerning the supposed reality that gives rise to it. In this chapter it will be argued that an enquiry into the metaphysical implications of science is certainly possible, but is not itself part of science. For science is limited in what it can tell us about reality. What is needed, it will be argued, is not more science, but the progressive development of higher and higher levels of explanation of the world that is revealed to us by science. For the aims of metaphysics are different from those of science, and the structures of metaphysical explanations are different from those of scientific explanations. Metaphysical explanations all proceed from the premise that truth supervenes on being. And the general question being asked is: how does it supervene? Scientific explanations make no such assumption, and scientific enquiries usually stop short of asking this question.

Science is not limited, as the early positivists believed it to be, to just describing what can be observed, and constructing theories that will enable scientists to make sound predictions concerning future observations.