by Jaegwon Kim
Jaegwon Kim is the William Herbert Perry Faunce Professor ofPhilosophy at Brown University. He is the author of Supervenience and Mind, Cambridge University Press, 1993; Philosophy of Mind, Westview, 1996; and Mind in a Physical World MIT Press, 1998 Jaegwon _Kim@brown.edu.
The following article appeared in Process Studies, pp. 28-34, Vol. 28 , Number 1-2, Spring- Summer, 1999. Process Studies is published quarterly by the Center for Process Studies, 1325 N. College Ave., Claremont, CA 91711. Used by permission. This material was prepared for Religion Online by Ted and Winnie Brock.
Kim responds to Griffin’s article, Materialist and Panexperientialist Physicalism: A Critique of Jaegwon Kim’s Supervienience and Mind. (See his article in www.religion-online.org.): Kim wrote his material over a long period of time, so much of his thought have changed. Hence, he does not so much answer as discuss ideas from Dr. Griffin’s comments.
In his "Materialist and Panexperientialist Physicalism" Professor David Griffin gives both a judicious and illuminating exposition and critique of the contemporary "mainstream" physicalism and a brief but clearly articulated synopsis of his own alternative approach which he calls "panexperientialism." Although Griffin’s discussion focuses on my own work, many of his points are applicable, more or less directly, to the broad physicalist framework within which much of current philosophical work in philosophy of mind is being carried on. The relevant papers of mine that Griffin discusses, all of them from my Supervenience and Mind,1 were written over a period of a dozen years, and my views on the issues involved continued to change and evolve during this time (needless to say, this process is still continuing). In view of this, I am especially impressed by Griffin’s ability to tell a reasonably coherent and intelligible story about my overall picture on the mind-body problem.
I consider the following three theses to be central to contemporary physicalism:
1. [Ontological physicalism] The space-time world is wholly constituted by basic bits of matter and their aggregates.
2. [Supervenience] Any two items -- things, events, phenomena, even whole worlds that are physically indiscernible are indiscernible tout court. Alternatively, physical facts determine all the facts.
3. [Causal closure of the physical domain] If any event causes a physical event, it itself is a physical event. In fact, any causal chain that involves at least one physical event must lie wholly within the physical domain.
As is well known, there are various inequivalent ways of stating these claims, but the slight differences between them will not matter for our purposes here. Ontological physicalism gives a sense to the idea that physics, the science of bits of matter in spacetime, is our basic science -- whatever its ultimate success may turn out to be, it is the only science that attempts to give us a comprehensive understanding of all of our world, Other sciences are "special sciences," in that each of them concerns a specially restricted domain. Only physics concerns the whole spacetime world.
Ontological physicalism only concerns the objects, or entities, in the world, and does not speak, at least not directly, about their properties. Properties come on the scene in the second thesis, the doctrine of supervenience; for physical indiscernibility is indiscernibility with respect to physical properties (and relations). Further, a physical fact is constituted by a physical object exemplifying a physical property, or a group of physical objects standing in some physical relationship. The supervenience thesis gives an explicit form to the idea that physical properties are primary and basic, and the physical properties an object instantiates -- that is, its physical nature -- determines all of its properties, that is, its entire nature. This of course allows things to have properties that are nonphysical, perhaps, certain physical aggregates with a high degree of systemic unity and organizational complexity, such as biological organisms and computing machines, may exhibit nonphysical properties.
The third thesis of physicalism, the principle of causal closure of the physical domain, guarantees the self-sufficiency of the domain: there are no nonphysical causal agents -- Cartesian souls, Hegelian spirits, or neovitalist entelechies -- that causally influence the behavior of physical objects or the course of physical processes.2 It also guarantees the explanatory sufficiency of physics: if a physical event has an explanation, it has a physical explanation. Note that this does not say that every physical event has an explanation, or a cause. In particular, the causal closure thesis does not entail physical determinism, and, further, physicalism does not entail determinism. It only says that physical events do not have nonphysical causes. If you deny the causal closure principle, you are saying that theoretical physics is in principle incompletable -- unless, that is, it invoked nonphysical causal agents. This might be the case; but if you believe that this in fact is the case, you are not a physicalist, and you wouldn’t want to be called a physicalist.
I believe that these three theses receive substantial -- for some people, compelling -- motivation and support from what we know about the world -- that is, our best sciences. To me, these are not ideal metaphysical speculations. Do I think they are all true? I believe that ontological physicalism is true, and that the physical causal closure is difficult to deny. I would like to believe in supervenience as well, but I don’t know if it is true. My reason for this hesitation is that I don’t know if qualia, the qualitative characters of our conscious experiences, are supervenient on physical/neural processes. This depends in part on the strength of the supervenience relation involved. However, I agree with many physicalists in thinking that a clear and satisfying form of physicalism must insist on supervenience with the force of metaphysical necessity -- for reasons that I cannot go into here. What I mean to say, then, is this: I do not know whether qualia supervene, with metaphysical necessity, on physical/neural states and processes. That is, I do not know that we can exclude metaphysically possible worlds that are physically indiscernible from this world but in which qualia are distributed differently -- or perhaps entirely absent.
In any case, that is physicalism. Qualia, as noted, present a fundamental challenge to physicalism. Another challenge comes from mental realism -- in particular the reality of mental causation. As Griffin correctly observes, I take mental realism and mental causation as essentially equivalent. If mental causation is real, then mental phenomena must be real. Conversely, any object or phenomenon in the spacetime world that we wish to recognize as real must have causal powers. That is what I have called "Alexander’s dictum," in honor of the British emergentist Samuel Alexander. Physicalism, however, is not the only thing a physicalist believes. I am a physicalist (modulo the qualia issue), but I believe lots of things other than physicalism. One of them is that mental phenomena are real, and that they have causal powers. The challenge to the physicalist is how to make his belief in the reality of mental causation consistent with his physicalism -- in particular, the physicalist must give an account of how mental events can exercise their causal powers in a physical world in a way that is consistent with the supervenience thesis and the physical causal closure. Griffin gives a lucid account of the conundrum – "the dead end" -- that the physicalist brings upon himself.3
Griffin says: "[Kim] takes his version of physicalism as more certain than our assumption as to the reality and thereby efficacy of conscious experience. I would agree with Whitehead . . . , by contrast, that those notions that we inevitably presuppose in practice should be regarded as the non-negotiable elements in our belief system" (12). I do not believe that I take physicalism as "more certain" than the causal efficacy of the mental. I’m not sure what "more certain" could mean in this context. For me this is not a question of epistemological priority but metaphysical priority. I believe that our own practical epistemic needs must not take metaphysical priority over what we believe to be the fundamental structure of reality, The former should nor dictate the latter. To me, reversing the order here is fundamentally inimical to the very idea of rationality and objectivity. If we want to protect consciousness, mental causation, and free agency we should give an account of how these things are possible within a scheme of a world mandated by theoretical reason -- our science and the best metaphysics that goes with it. To me, it is a form of philosophical indulgence to purposely and consciously build into our foundational metaphysics exactly what we want to protect and save. Doing metaphysics is difficult and rewarding because we want to begin with an austere fund of basic resources and try to get, and explain, other things that we want out of it. To begin metaphysics ‘with all that we want to preserve is a form of what Frank Jackson has called "big list" metaphysics: you would be doing this kind of metaphysics if your ontology consisted merely of making up a list of all that you believe to exist.4 "Serious metaphysics," as Jackson calls it, enters the scene when you begin with an austere and sparse foundation and endeavor to show that it is enough to yield the things you want to save.
I am not suggesting that Griffin begins with all that he wants to save in the way of human consciousness, mental causation, and free agency. That would have been a "wish list" metaphysics," to go along with Jackson’s "big list" metaphysics. But Griffin’s metaphysical foundation -- the foundation of his panexperientialism -- does remind one of a metaphysical wish list. For consider his "individuals." I am not sure exactly what individuals, in general terms, are in Griffin’s (or Whitehead’s) system, but he writes:
Second, laws applying to genuine individuals, whether simple or compound, would be statistical, because all individuals have at least an iota of mentality and thereby spontaneity. This prediction is fulfilled, for example, by the laws of quantum mechanics, which predictively describe the behavior of groups of particles, not that of any individual particle. (24)
As I take it, the basic particles of physics are, or are among, Griffin’s "simple individuals," and each of them has some sort of proto-mentality, which endows it with "spontaneity" and "creativity." Moreover, it is because of these individuals’ spontaneity and creativity that the laws governing them, that is, quantum mechanical laws, are statistical and nor deterministic. Although I don’t know the details, which I am certain are worked out systematically in Griffin’s book, Unsnarling the World-Knot,5 this talk of spontaneity and creativity appears to indicate the presence of some form of proto-agency even in "simple individuals." I am reminded here of what William James once said:
If evolution is to work smoothly, consciousness in some shape must have been present at the very origin of things. Accordingly, we find that the more clear-sighted evolutionary philosophers are beginning to posit it there. Each atom of the nebula, they suppose, must have had an aboriginal atom of consciousness linked with it.6
The basic idea here appears to be something like this: we know that consciousness has emerged from the process of evolution. But unless we posit consciousness at the starting point, there is no way of accounting for the existence of consciousness. So we must endow each and every atom with some form of "aboriginal consciousness" – "Mind-dust" as James calls it.7
Note that neither Griffin’s nor James’s procedure is exactly what I called "wish list" metaphysics. For what they posit at the beginning, or at the bottom level, is not full-flown mentality or free agency, of the sorts we see in humans, but some sort of "aboriginal" or proto-mentality, or, to use Griffin’s words, "an iota of mentality." But what I don’t see is how this really helps. How are we supposed to derive human consciousness -- our rationality and intentionality, our richly variegated qualitative experiences, our sense of free choice, our complex and highly developed agency -- from the aboriginal mentality of the simple individuals, presumably the basic particles, that constitute us? For Griffin, we are "compounds," not mere "aggregates," of simple individuals, and this makes us genuine individuals. He regards individual cells to be endowed with mentality. He says that "the brain cells are themselves regarded as centers of experience," and that "living cells themselves provide a lower-level example, in that the cell’s living occasions of experience have emerged out of the cell’s more elementary constituents" (19-20). But exactly how is the positing of mentality at the level of individual cells and neurons supposed to help explain the emergence of full-blown consciousness in the human brain?8 Just what sort of mentality is the supposed proto-mentality possessed by basic particles, and how does a "compound" made up of these particles get to have a resultant mentality of a certain kind? I suppose that Griffin’s notion of a "compound" must do most of the work if these questions are to be answered. In particular, what I would like to see is an independently motivated and defended principle that tells us that if something X is a compound individual composed of individuals x1 . . . , xn each with a certain specific kind and degree of mentality and in a certain structural configuration R, then X exhibits mentality of some specific kind M.
Although Griffin refers to his position as a form of emergentism, it clearly is not a form of classic emergentism. The classic emergentism of Samuel Alexander, C. Lloyd Morgan, and C. D. Broad would nor accept basic material particles with a "mental pole." The emergentism these philosophers defended accepted ontological physicalism, where the "bits of matter" are nothing but bits of matter without anything mental to them. For them mentality was a true emergent, and what they regarded as a brute and unexplainable fact is that mentality emerges when certain physical/biological conditions are realized. Alexander advised us to accept this with "natural piety." In this sense, these emergentists were austere metaphysicians, and they would have rejected Griffin’s and Whitehead’s framework in which the basic constituents of the world are given some form of mentality as ad hoc and ultimately not very helpful. Furthermore, as is clear from the title of his essay, Griffin believes that his approach is, or can be considered, a form of physicalism. This is a gracious gesture on his part, but I am inclined to think it misleading to regard panexperientialism as any form of physicalism. I believe that this position is inconsistent with each of the three doctrines (understood in their proper intended sense) that I listed above as central to contemporary physicalism.
Finally, I would like to correct one point in Griffin’s discussion of my views, since it represents one kind of misapprehension that seems widely spread among the critics of physicalism, and even among some physicalists (especially, of the nonreductive variety). I am willing to take the blame for this since the lack of clarity in my writings has undoubtedly helped abet the misunderstanding. Griffin writes:
. . . all things big enough to be directly observed would be of the same type: We could not regard living cells or multi-celled animals as being or containing, higher-level actualities to which causal efficacy could be attributed. We would have to think of them, with Kim, as ontologically decomposable into atoms and other basic physical particles," to which all causal efficacy would be assigned. (18)
A bit later, he says: "All observable things are of the same organizational type, so that human beings are analogous to material things such as rocks and bodies of water."(19). Here Griffin is not speaking for himself; rather, he is drawing what he considers to be the consequences of the kind of physicalism I espouse – specifically, the mereological supervenience of macro-properties on micro-properties.
Griffin appears to be reasoning as follows: mereological supervenience says that the properties characteristic of wholes are supervenient on, or determined by, the properties of their parts, and ultimately, therefore, the properties of the basic particles that make them up. And the causal powers of these wholes must, too, be supervenient on the properties of these basic microconstituents, and reduce to them. Now compare a human being and a rock: at bottom they are made up of pretty much the same basic particles -- electrons, protons, neutrons, quarks, and what have you. So, on this view, there can be no principled difference between human beings and animals ("genuine individuals"), on one hand, and rocks, clouds, and water puddles ("mere aggregates"), on the other. In fact, it is a mystery; on this account, how the causal powers of human beings can differ from those of rocks.
If this indeed is Griffin’s thought, it can be rebutted. Mereological supervenience only asserts that the properties of the whole are determined, or fixed, by the properties and relations that characterize its parts. That only means that if two wholes are microstructurally identical, they must exhibit the same macroproperties -- and the same causal powers. And these can be new causal powers; it is only that they are determined by microstructure. Mereological supervenience does not say, or imply, that the properties of the whole are identical with properties of their microconstituents. As emergentists, too, would say; such properties as inflammability, ductility, and temperature of macro-objects are not among the properties of individual molecules or atoms. For both emergentists and (most) physicalists. they are genuine properties and causal powers, which supervene on, or are determined by the microstructural makeup of the objects that have them. Emergentists and physicalists would stress that the Structural configuration, no less than the intrinsic properties, of microconstituents is crucial in determining what macro-properties are exhibited by a whole. For wholes -- anyway, those of interest to us -- are structures, not mere assemblages of atoms and particles, and the very same atoms and particles configured in different structural relationships can, and do, exhibit very different properties and causal powers at thc level of wholes. And many of these properties are not had by the wholes’ micro-constituents. This is completely consistent with physicalism, and in particular with mereological supervenience and micro-reductionism. Thus, two points: first, determination must be sharply distinguished from identity’ and, second, structure is crucially important. These points would have been acknowledged by many classic emergentists as well, including C. D. Broad.
Griffin’s essays poses serious challenges to contemporary physicalism, not only because it forces physicalists to return to the beginnings and re-examine their fundamental assumptions but, more importantly, because it does so by proposing a radical, thought-provoking alternative. I do not presume to have grasped the details and full import of Griffin’s approach. The main question I will have to keep in mind as I read his book (as I hope to in the near future) is whether, and to what extent, the panpsychic approach he espouses helps us to understand "the mystery of consciousness" -- that is, just how it does its job better here than the various well-known forms of contemporary physicalism. Finally, we should all be grateful to Professor Griffin for his important service in bringing the Whiteheadian perspective to bear on current debates in the analytical philosophy of mind and showing how the two approaches can be relevant to each other, especially in regard to our shared concern to understand the place of the mind in the natural world.
1. Jaegwon Kim, Supervenience and Mind (Cambridge: Cambridge University Press, 1993).
2. Does ontological physicalism imply the causal closure of the physical domain? No, because, as noted, the supervenience doctrine allows physical systems to have nonphysical properties, and these nonphysical properties might causally interact with physical properties.
3. For additional considerations see my Mind in a Physical World (Cambridge MIT Press, forthcoming.)
4. See, e.g., Frank Jackson, "Finding the Mind in the Natural World," in Philosophy and Cognitive Science, ed. R. Casati, B. Smith, and G. White (Vienna: Verlag Hoelder-Pichler, 1994).
5. David Ray Griffin, Unsnarling the World-Knot (Berkeley: University of California Press, 1998).
6. William James, The Principles of Psychology (Cambridge Harvard University Press, 1983; originally published in 1890), 152 (italics in the original. I came upon this paragraph in James Van Cleve’s "Mind-Dust or Magic? Panpsychism versus Emergence," Philosophical Perspectives 4 (1990), 215-226.
7.And I have heard philosophers say that there is consciousness "all the way down" -- down to the level of elementary particles, quarks. or what have you.
8. Van Cleve, in the article cited in note 4, raises similar questions.
9. There is another distinction that is often overlooked (but not by classic emergentists): to be determined by such-and-such is one thing, to be explainable by such-and-such is another thing. On the standard conception, emergents are determined by their "basic conditions" but not explainable by them. At least, the concept of determination here does not entail explainability.