Metaphysics

2. Specific metaphysics

There is also metaphysics that arises in reference to particular subject matters, this being therefore metaphysical primarily with regard to the second question (what are things ultimately like? – or, what kinds of thing ultimately exist?) rather than the first. One of the most obvious cases, and historically the most prominent, is theology; we have already mentioned the philosophy of mind, the philosophy of mathematics and the theory of values. Less obviously, metaphysical issues also intrude on the philosophy of language and logic, as happens when it is suggested that any satisfactory theory of meaning will have to posit the existence of intensional entities, or that any meaningful language will have to mirror the structure of the world (see Intensional entities; Logical atomism). The political theorist or social scientist who holds that successful explanation in the social sphere must proceed from properties of societies not reducible to properties of the individuals who make them up (thereby making a society an entity that is in a sense more basic than its members) raises a metaphysical issue (see Holism and individualism in history and social science). Metaphysics, as demarcated by the second question, can pop up anywhere.

The relationship with metaphysics is, however, particularly close in the case of science and the philosophy of science. Aristotle seems to have understood his ‘first philosophy’ as continuous with what is now called his physics, and indeed it can be said that the more fundamental branches of natural science are a kind of metaphysics as it is characterized here. For they are typically concerned with the discovery of laws and entities that are completely general, in the sense that everything is composed of entities and obeys laws. The differences are primarily epistemological ones, the balance of a priori considerations and empirical detail used by scientists and philosophers in supporting their respective ontological claims. The subject matter of these claims can even sometimes coincide: during the 1980s the reality of possible worlds other than the actual one was maintained by a number of writers for a variety of reasons, some of them recognizably ‘scientific’, some recognizably ‘philosophical’ (see Possible worlds). And whereas we find everywhere in metaphysics a debate over whether claims should be given a realist or an antirealist interpretation, in the philosophy of science we find a parallel controversy over the status of the entities featuring in scientific theories (see Realism and antirealism; Scientific realism and antirealism).

It is true that there has been considerable reluctance to acknowledge any such continuity. A principal source of this reluctance has been logical positivism, with its division of propositions into those which are empirically verifiable and meaningful, and those which are not so verifiable and are either analytic or meaningless, followed up by its equation of science with the former and metaphysics with the latter (see Demarcation problem; Logical positivism; Meaning and verification). When combined with the belief that analytic truths record nothing about the world, but only about linguistic convention, this yields a total rejection of all metaphysics – let alone of any continuity with science. But apart from the fact that this line of thought requires acceptance of the principle about meaninglessness, it also makes a dubious epistemological assumption: that what we call science never uses non-empirical arguments, and that what we regard as metaphysics never draws on empirical premises. Enemies of obscurantism need not commit themselves to any of this; they can recognize the continuity between science and metaphysics without robbing anyone of the vocabulary in which to be rude about the more extravagant, ill-evidenced, even barely meaningful forms which, in the view of some, metaphysics has sometimes taken.

Even the philosopher with a low opinion of the prospects for traditional metaphysics can believe that there is a general framework which we in fact use for thinking about reality, and can undertake to describe and explore it. This project, which can claim an illustrious ancestor in Kant, has in the twentieth century sometimes been called descriptive metaphysics, though what it inquires into are our most general patterns of thought, and the nature of things themselves only indirectly, if at all. Though quite compatible with a low estimate of traditional metaphysics as defined by our two primary questions, it does imply that there is a small but fairly stable core of human thought for it to investigate. Hence it collides with the view of those who deny that there is any such thing (see Postmodernism).