Contemporary Materialism

A Reader

Paul K. Moser, J. D. Trout, Paul K. Moser, J. D. Trout

• Publisher: Routledge
• Year: 2002
• ISBN:
  9781134839339
• Edition: 1
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

Contemporary Materialism brings together the best recent work on materialism from many of our leading contemporary philosophers. This is the first comprehensive reader on the subject. The majority of philosophers and scientists today hold the view that all phenomena are physical, as a result materialism or 'physicalism' is now the dominant ontology in a wide range of fields. Surprisingly no single book, until now, has collected the key investigations into materialism, to reflect the impact it has had on current thinking in metaphysics, philosophy of mind and the theory of value. The classic papers in this collection chart contemporary problems, positions and themes in materialism. At the invitation of the editors, many of the papers have been specially up-dated for this collection: follow-on pieces written by the contributors enable them to appraise the original paper and assess developments since the work was first published. The book's selections are largely non-technical and accessible to advanced undergraduates. The editors have provided a useful general introduction, outlining and contextualising this central system of thought, as well as a topical bibliography. Contemporary Materialism will be vital reading for anyone concerned to discover the ideas underlying contemporary philosophy. David Armstrong, University of Sydney; Jerry Fodor, Rutgers University, New Jersey; Tim Crane, University College, London; D. H. Mellor, Univeristy of Cambridge; J.J.C.

Part I
Materialism and Naturalism

1
Naturalism, Materialism, and First Philosophy

David M.Armstrong

In the first section of this paper, I define and defend a spatio-temporal account of the general nature of reality. I call this doctrine “Naturalism”. In the second section, I define and defend the somewhat more specific, although still very general, doctrine of Materialism or Physicalism. (I take it to be a sub-species of Naturalism.) However, if we define ontology or “first philosophy” as the most abstract or general theory of reality, then it seems that neither Materialism nor even Naturalism is an ontology. In the third section, I sketch very briefly the ontology I favour. Unlike that adopted by many Naturalists and Materialists, it admits both particulars and universals. It is Realistic, not Nominalistic. I maintain, in particular, that only by adopting a Realistic (but not Platonistic) account of universals can the Naturalist and the Materialist solve the pressing problems of the nature of causation and of law-like connection.

NATURALISM

Naturalism I define as the doctrine that reality consists of nothing but a single all-embracing spatio-temporal system. It is convenient here to distinguish this proposition from the weaker claim that reality at least contains as a part a spatio-temporal system. I will say something in defence of the weaker claim first, and then defend the view that reality is nothing but this spatio-temporal system.

It is difficult to deny that a spatio-temporal system appears to exist. But, of course, many philosophers have denied that this appearance is a reality. Leibniz is an example. He held that reality consists of the monads and that space and time are illusions, even if illusions that have some systematic link with reality. Leibniz was at least a pluralist. But for Parmenides, for Hegel and for Bradley, reality is not a plurality but is simply one. The spatiotemporal system is an appearance that completely or almost completely misrepresents the one.

I will not spend any time considering such views, despite their importance. The arguments used to establish them are all a priori. I believe that they can all be answered. But in any case, as an Empiricist, I reject the whole conception of establishing such results by a priori argumentation.

But the Naturalist may seem to face a challenge to the view that there is a spatio-temporal system from a source that he must take more seriously: from natural science itself. It is the impression of an outsider like myself that some speculations in fundamental physics lead to the conclusion that, at deep levels of explanation, space and time dissolve and require to be replaced by other, more fundamental, principles.

However, I suggest that such speculations need not perturb the Naturalist. I believe that he should draw the familiar distinction between denying that a certain entity exists and giving an account of that entity in terms of other entities. It is a very extreme view to deny that the world has spatiotemporal features. I find it hard to believe that even the most far-fetched speculations in fundamental physics require such a denial. But it involves no such denial to assert that the spatio-temporal features of things can be ultimately analysed in terms that do not involve any appeal to spatiotemporal notions. The Naturalist, as I have defined Naturalism, is committed to the assertion that there is a spatio-temporal system. But why is he committed to asserting that spatio-temporality cannot be analysed in terms of non-spatio-temporal principles? What is not ultimate may yet be real. I suppose that if the principles involved were completely different from the current principles of physics, in particular if they involve appeal to mental entities, such as purposes, we might then count the analysis as a falsification of Naturalism. But the Naturalist need make no more concession than this.

Consider, as a parallel example, the attitude of Materialists towards purposes. There are some Materialists who deny that men and other organisms have purposes. This seems to me to be a quite foolish position to adopt. Materialism may be true—my hypothesis is that it is true—but it is a speculative doctrine. The existence of purposes, on the other hand, is a plain matter of fact. The prudent Materialist therefore will argue in the following way. There is no reason to believe that what it is for an organism to have a purpose involves anything more than the operation of purely physical processes in the organism. (These mechanisms are, perhaps, very sophisticated cybernetic processes.) In this way, an account of purposes is proposed in terms of processes that do not themselves involve purpose. No doubt this is a somewhat deflationary view of what a purpose is. But it is a view of the nature of purposes, not a denial of them.

Spatio-temporality may be analysed, just as the Materialist claims that purpose can be analysed. However, in default of some quite extraordinary analysis of spatio-temporality—say, in terms of spiritual principles— Naturalism is not thereby falsified. But, just as it is an incredible view that purposes can be analysed away, so, I think, it is an incredible view that spatio-temporality could be analysed away. A priori reasoning should not convince us of the unreality of space and time. Nor, I have just argued, is it at all plausible that a posteriori reasoning will ever drive us to the same conclusion.

So much by way of brief defence of the positive content of Naturalism. I turn now to its negative contention: that the world is nothing more than a spatio-temporal system. Here we find that philosophers and others have postulated a bewildering variety of additional entities. Most doctrines of God place him beyond space and time. Then there are transcendent universals, the realm of numbers, transcendent standards of value, timeless propositions, non-existent objects such as the golden mountain, possibilities over and above actualities (“possible worlds”), and “abstract” classes, including that most dilute of all entities: the null-class. Dualist theories of mind are interesting intermediate cases, because they place the mind in time but not in space. The same holds for some theories of God and also, apparently, for Karl Popper’s recently proposed “third world” of theories, which interacts with the “second” world of mind (Popper, 1973: chs. 3–4).

Despite the incredible diversity of these postulations, it seems that the Naturalist can advance a single, very powerful, line of argument that is a difficulty for them all. The argument takes the form of a dilemma. Are these entities, or are they not, capable of action upon the spatio-temporal system? Do these entities, or do they not, act in nature?

In the case of many of these entities, they were at least originally conceived of as acting in nature. God acted in the world. The Forms in Plato’s Phaedo are causes, and the Forms were apparently transcendent universals, as well as being transcendent numbers and transcendent standards of value. Descartes’ spiritual substances interact with matter, and Popper’s “third world” interacts with the “second world” of mind, which in turn interacts with material things.

Nevertheless, there are very great difficulties involved in holding that any of these transcendent entities act upon the spatio-temporal system.

First, there are logical or conceptual difficulties. A great many of these entities are not thought of as capable of change. This holds for transcendent universals, the realm of numbers and values, propositions, non-existent objects, possible worlds and abstract classes. In many theological systems, God is taken not to change. Now in typical cases of causation, one change brings about another. It follows that, if these entities work causally in the world, they do not work in this typical way. How, then, do they work? Could they be conceived of as sustaining certain features of the natural world, or as exerting some sort of steady, unchanging, pressure upon it that, when certain circumstances arise in nature, gives rise to certain effects? Such a notion is perhaps barely possible, but the actual identification of such alleged causal operation is a major difficulty. For instance, where sustaining causes are postulated in nature, hypotheses about such causes can be tested by observing situations where the alleged sustaining cause is absent. If the alleged effect is also absent, the hypothesis is supported. But no such verification is possible, even in principle, in the case of unchanging entities. In the Parmenides (133b–134e), Plato goes so far as to raise logical difficulties for the conception of any relation at all (and so, a fortiori, a causal one) between the Forms and spatio-temporal particulars.

Even in the relatively straightforward case of the interaction of spiritual substance with material body, conceptual difficulties have been raised. For instance, the impossibility of specifying any mechanism or other explanation of how the spirit acts upon its body has been thought to be a problem. Descartes himself, as evidenced in particular by his correspondence with Princess Elizabeth, thought that the action of spirit on matter involved some conceptual difficulty.

In the case of many of the postulated transcendent entities, there never was any thought of crediting them with causal power in the natural world. Possible worlds, for instance, are not thought to act upon the actual world. But even in the case of entities originally credited with power in the natural world, considerations of the sort just sketched have been an important pressure towards denying that they had such power.

I confess, however, that it is not upon these conceptual difficulties that I, as a Naturalist, would place the most weight. Instead, I would appeal to natural science. It seems to me that the development of the natural sciences very strongly suggests that Nature, the spatio-temporal system, is a causally self-enclosed system. We have rather good scientific reasons to believe that, whatever occurs in this system, if it has a cause at all, is caused solely by other events (processes etc.) in the spatio-temporal system. Of course, this proposition is not susceptible of strict proof. But in the present state of scientific knowledge, it looks a promising bet.

In the past, religious thinkers thought of God as intervening freely in the spatio-temporal world. He might give victory to the righteous or answer prayers for rain in defiance of the way that matters would have shaped if the spatio-temporal system had been left to its own devices. But even those who still believe in a transcendent God are increasingly reluctant to believe that he acts upon Nature in this way. They hold that he created it, and created it for a purpose which is working itself out. But does he ever intervene?

Consider, again, the Dualist theory of the mind. Descartes saw clearly that, if Dualist Interactionism was to be made plausible, then he must postulate places in the human brain where physical events occurred, the immediate causes of which were, in part at least, spiritual happenings. He guessed that this happened in the pineal gland, but we now know that the pineal gland can play no such role. Where, then, do spiritual happenings have their immediate physical effects? Nobody has come up with a plausible suggestion. Most neurophysiologists would be astounded to hear that what happens to the brain has any other cause except earlier states of the brain and its physical environment.

Yet the cases of God and the soul are the two most plausible cases of things outside the spatio-temporal system acting upon it. (It is noteworthy that they are the two examples that non-philosophers would be most likely to give of things outside Nature acting upon Nature.) If the anti-Naturalist case is weak here, it is far more unpromising in the other cases. Suppose, for instance, that there is a transcendent realm of numbers. How scientifically implausible to think that this realm, or members of this realm, can act on brains!

So let us now explore the other horn of the dilemma. Let us assume that no transcendent entity acts in nature. I maintain that this remedy is worse than the disease. The anti-Naturalist goes from a hot frying-pan into a blazing fire.

The argument is simply this. The spatio-temporal system certainly exists. Whether anything else exists is controversial. If any entities outside the system are postulated, but have no effect on the system, there is no compelling reason to postulate them. Occam’s razor then enjoins us not to postulate them.

Natural science has made spectacular advances as a result of the postulation of unobservable entities. Consider microbes, genes, atoms, molecules, electrons, quarks and black holes. The value of such postulations is a standing reproach to any positivistic conception of natural science. Now, contemporary analytic philosophers are deeply affected by the justified reaction against positivism. As a result, the fashionable defence of transcendent entities is to compare them with the theoretical entities of natural science of the sort just mentioned. For instance, “abstract” classes (classes over and above the aggregates of their members) are postulated on the ground that, by their means, we can explain what mathematics is about, mathematics which in turn is required for the truth of physics, which explains the workings of Nature. The justification for the introduction of abstract classes is thus no different from the justification for the introduction of electrons.

In fact, however, the resemblance is superficial only. There is this vital difference. Abstract classes, to continue with these as our example, provide objects the existence of which, perhaps, can serve as the truth-conditions for the propositions of mathematics. But this semantic function is the only function that they perform. They do not bring about anything physical in the way that genes and electrons do. In what way, then, can they help to explain the behaviour of physical things? Physics requires mathematics. That is not in dispute. But must...