280 Robin Collins
Forster, M. (2006) Counterexamples to a likelihood theory of evidence. Minds and Machines 16: 3, 319–38. Available at: http://philosophy.wisc.edu/forster (accessed May 6, 2008).
Forster, M. and Sober, E. (2001) Why likelihood? In M. Taper and S. Lee (eds.), The Nature of Scientifi c Evidence. Chicago: University of Chicago Press. Available at: http://philosophy.wisc.edu/forster (accessed May 6, 2008).
van Fraassen, B. (1980) The Scientifi c Image. Oxford: Clarendon Press.
Greene, B. (1999) The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory. New York: W. W. Norton and Co.
Guth, A. (1997) The Infl ationary Universe: The Quest for a New Theory of Cosmic Origins. New York: Helix Books.
Hacking, I. (1975) The Emergence of Probability: A Philosophical Study of Early Ideas about Probability, Induction and Statistical Inference. Cambridge: Cambridge University Press.
Hacking, I. (1987) Coincidences: mundane and cosmological. In J. M. Robson (ed.), Origin and Evolution of the Universe: Evidence for Design, 119–38. Montreal: McGill-Queen’s University Press.
Holder, R. (2004) God, the Multiverse, and Everything: Modern Cosmology and the Argument from Design. Burlington, VT: Ashgate.
Howson, C. (1991) Discussion: the old evidence problem. The British Journal for the Philosophy of Science 42, 547–55.
Hume, D. (1980) Dialogues concerning Natural Religion and the Posthumous Essays. Ed. R. Popkin.
Indianapolis, IN: Hackett Publishing Co.
Kaku, M. (1999) Introduction to Superstrings and M-Theory, 2nd edn. New York: Springer-Verlag.
Keynes, J. M. (1921) A Treatise on Probability. London: Macmillan.
Kiessling, M. (2001) How to implement Boltzmann’s probabilistic ideas in a relativistic world? In J. Bricmont, D. Dürr, M. C. Galavotti, G. Ghirardi, F. Petruccione, N. Zanghi (eds.), Chance in Physics, 83–102. Berlin: Springer-Verlag.
Kolda, C. and Lyth, D. (1999) Quintessential diffi culties. http://arxiv.org/PS_cache/hep-ph/pdf/9811/
9811375v3.pdf (accessed April 10, 2008).
Koperski, J. (2005) Should we care about fi ne-tuning? The British Journal for the Philosophy of Science 56: 2, 303–19.
Leslie, J. (1988) How to draw conclusions from a fi ne-tuned cosmos. In R. J. Russell W. R. Stoeger, G. V. Coyne (eds.), Physics, Philosophy and Theology: A Common Quest for Understanding, 297–
312. Vatican City State: Vatican Observatory Press.
Leslie, J. (1989) Universes. New York: Routledge.
Leslie, J. (1998) Cosmology and philosophy. Stanford Encyclopedia of Philosophy. Available at: http://
plato.stanford.edu/archives/fall1998/entries/cosmology-theology/ (accessed October, 2007).
Lewis, D. (1986) On the Plurality of Worlds. New York: Basil Blackwell.
Linde, A. (1990) Particle Physics and Infl ationary Cosmology. Trans. M. Damashek. Longhorne, PA: Harwood Academic Publishers.
Mackie, J. L. (1982) The Miracle of Theism. Oxford: Clarendon Press.
Mann, R. (2005) Inconstant multiverse. Perspectives on Science and the Christian Faith 57: 4, 302–10.
McGinn, C. (1999) The Mysterious Flame: Conscious Minds in a Material World. New York: Basic Books.
McGrew, T. and McGrew, L. (2005) A response to Robin Collins and Alexander R. Pruss. Philosophia Christi 7, 425–43.
McGrew, T., McGrew, L., and Vestrup, E. (2001) Probabilities and the fi ne-tuning argument: a skeptical view. Mind 110, 1027–38.
Mena, O. and Santiago, J. (2006) Constraining inverse-curvature gravity with supernovae. Physical Review Letters 96, 041103.
Narlikar, J. V. (2002) An Introduction to Cosmology, 3rd edn. Cambridge: Cambridge University Press.
Oppy, G. (2006) Arguing about Gods. Cambridge: Cambridge University Press.
Otte, R. (2006) Counterfactuals and epistemic probability. Synthese 152: 1, 83–94.
Page, D. (2006) Is our universe decaying at an astronomical rate? http://arxiv.org/abs/hep-th/0612137
(accessed April 10, 2008).
Parsons, K. (1990) Is there a case for Christian theism? In J. P. Moreland and K. Nielsen (eds.), Does God Exist? The Great Debate, 177–96. Nashville, TN: Thomas Nelson.
Peacock, J. (1999) Cosmological Physics. Cambridge: Cambridge University Press.
Penrose, R. (1989) The Emperor’s New Mind: Concerning Computers, Minds, and the Laws of Physics.
New York: Oxford University Press.
T E L E O LO G I C A L
A RG U M E N T 281
Penrose, R. (2004) The Road to Reality: A Complete Guide to the Laws of the Universe. New York: Alfred A. Knopf.
Plantinga, A. (1993) Warrant and Proper Function. Oxford: Oxford University Press.
Plantinga, A. (2000) Warranted Christian Belief. Oxford: Oxford University Press.
Polchinski, J. (1998) String Theory, vols. I and II. Cambridge Monographs in Mathematical Physics.
Cambridge: Cambridge University Press.
Rees, M. (2000) Just Six Numbers: The Deep Forces that Shape the Universe, New York: Basic Books.
Rice, H. (2000) God and Goodness. Oxford: Oxford University Press.
Royall, R. (1997) Statistical Evidence – A Likelihood Paradigm. London: Chapman and Hall.
Sahni, V. and Starobinsky, A. (1999) The case for a positive cosmological lambda-term. http://arxiv.
org/abs/astro-ph/9904398 (accessed March 15, 2008).
Salmon, W. (1984) Scientifi c Explanation and the Causal Structure of the World. Princeton, NJ: Princeton University Press.
Schlesinger, G. (1985) The Intelligibility of Nature. Aberdeen, Scotland: Aberdeen University Press.
Smart, J. C. (1985) Laws of nature and cosmic coincidence. The Philosophical Quarterly 35: 140, 272–80.
Smolin, L. (1997) The Life of the Cosmos. Oxford: Oxford University Press.
Sober, E. (2002) Bayesianism – its scope and limits. In R. Swinburne (ed.), Bayes’s Theorem, 21–38.
Oxford: Oxford University Press.
Sober, E. (2005) The design argument. In W. Mann (ed.), The Blackwell Guide to the Philosophy of Religion, 117–48. Oxford: Blackwell.
Stenger, V. (2000) Natural explanations for the anthropic coincidences. Philo 3: 2, 50–67.
Stenger, V. (2004) Is the universe fi ne-tuned for us. In M. Young and T. Edis (eds.), Why Intelligent Design Fails: A Scientifi c Critique of the New Creationism, 172–84. New Brunswick, NJ: Rutgers University Press.
Stenger, V. (2007) God: The Failed Hypothesis: How Science Shows That God Does Not Exist. Amherst, NY: Prometheus Books.
Swinburne, R. (2001) Epistemic Justifi cation. Oxford: Clarendon Press.
Swinburne, R. (2004) The Existence of God, 2nd edn. Oxford: Oxford University Press.
Tegmark, M. (1998) Is the theory of everything merely the ultimate ensemble theory? Annals of Physics 270, 1–51.
Tegmark, M. (2003) Parallel universes. Scientifi c American, May, 41–51. (Also see Parallel universes.
In J. D. Barrow, P. C. W. Davies, and C. L. Harper (eds.), Science and Ultimate Reality: From Quantum to Cosmos. Cambridge University Press, 2003. Also available at: http://arxiv.org/abs/
astro-ph/0302131).
Teller, P. (1988) Three problems of renormalization. In R. Harré and H. Brown (eds.), Philosophical Foundations of Quantum Field Theory, 73–89. Oxford: Clarendon Press.
Wald, R. (1984) General Relativity. Chicago: University of Chicago Press.
Ward, K. (1987) Concepts of God: Images of the Divine in Five Religious Traditions. Oxford: Oneworld Publications.
Weatherford, R. (1982) Foundations of Probability Theory. Boston: Routledge and Kegan Paul.
White, R. (2000) Fine-tuning and multiple universes. Nous 34, 260–76. Reprinted in N. Manson (ed.), God and Design: The Teleological Argument and Modern Science, 229–50. London: Routledge, 2003).
Zee, A. (2003) Quantum Field Theory in a Nutshell. Princeton, NJ: Princeton University Press.
The Argument from
Consciousness
J. P. MORELAND
Section One: The Backdrop for Locating Consciousness
in a Naturalist Ontology
Consciousness is among the most mystifying features of the cosmos (see Moreland 2008).
During the emergence of the mechanical philosophy in the seventeenth century, Leibniz wrote the following as a challenge to mechanistic materialism:
It must be confessed, moreover, that perception, and that which depends on it are inexplicable by mechanical cause, that is by fi gures and motions. And supposing there were a machine so constructed as to think, feel and have perception, we could conceive of it as enlarged and yet preserving the same proportions, so that we might enter it as a mill. And this granted, we should only fi nd on visiting it, pieces which push one against another, but never anything by which to explain a perception. This must be sought for, therefore, in the simple substance and not in the composite or in the machine. (Leibniz 1979, p. 536)
And while different bells and whistles have been added to our conception of matter since Leibniz’s time, scientifi c naturalist explanations for the emergence of consciousness are as inadequate today as they were when Leibniz threw down his gauntlet. As Geoffrey Madell opines, “the emergence of consciousness, then is a mystery, and one to which materialism signally fails to provide an answer” (Madell 1988, p. 141).
Not only are adequate naturalistic explanations for irreducible consciousness hard to come by, there is a widespread suspicion, if not explicit acknowledgement that irreducible consciousness provides evidence for theism. Thus, Crispin Wright notes:
A central dilemma in contemporary metaphysics is to fi nd a place for certain anthropocentric subject-matters—for instance, semantic, moral, and psychological—in a world as conceived by modern naturalism: a stance which infl ates the concepts and categories deployed by (fi nished) physical science into a metaphysics of the kind of thing the real world essentially and exhaustively is. On one horn, if we embrace this naturalism, it seems we are committed either to reductionism: that is, to a construal of the reference of, for example, semantic, moral and psychological vocabulary as somehow being within the physical domain—or to disputing that The Blackwell Companion to Natural Theology Edited William Lane Craig and J. P. Moreland
© 2009 Blackwell Publishing Ltd. ISBN: 978-1-405-17657-6
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the discourses in question involve reference to what is real at all. On the other horn, if we reject this naturalism, then we accept that there is more to the world than can be embraced within a physicalist ontology—and so take on a commitment, it can seem, to a kind of eerie supernaturalism. (Wright 2002, p. 401)
Similarly, William Lyons claims that:
[physicalism] seem[s] to be in tune with the scientifi c materialism of the twentieth century because it [is] a harmonic of the general theme that all there is in the universe is matter and energy and motion and that humans are a product of the evolution of species just as much as buffaloes and beavers are. Evolution is a seamless garment with no holes wherein souls might be inserted from above. (Lyons 1995, p. lv)
Souls being “inserted from above” is a veiled reference to theism’s explanatory power for consciousness: If “souls” exist, they would have to be “inserted from above”, since natural processes by themselves are “seamless.” Some argue that, while certain features of fi nite mental entities may be inexplicable on a naturalist worldview, they may be explained by theism, thereby furnishing evidence for God’s existence. For some time, mental entities have been recalcitrant facts for naturalists. Indeed, for philosophers who take the issues and options in philosophy of mind to be signifi cantly infl uenced by empirical considerations, the proliferation of a wild variety of physicalist specifi cations of a naturalist treatment of mental phenomena may fairly be taken as a sign that naturalism is in a period of Kuhnian paradigm crisis. The argument from consciousness for God’s existence (hereafter, AC) provides a way of dethroning the naturalist hegemony. Moreover, by giving a more adequate analysis of and explanation for mental entities, it provides a way out of the crisis and, together with other lines of evidence, offers materials for a cumulative case argument for theism.1
For decades, versions of naturalism have multiplied like rabbits, so before we examine AC and its chief rivals, it is important to clarify two factors that constitute the dialectical background for what follows. First, I shall unpack the ideational structure of a version of naturalism that follows most plausibly from taking it as a worldview that claims explanatory, epistemic superiority to its rivals. Second, I shall lay out the central epistemic conditions relevant to assessing the force of AC vis-à-vis naturalism.
While there will be different nuances given to naturalism by different thinkers, it is still possible to give an accurate characterization of a specifi c form of philosophical naturalism (hereafter, simply naturalism or scientifi c naturalism) that is currently enjoying widespread acceptance (cf. Rosenberg 1996; Moreland & Craig 2000). And by clarifying the relationship between a naturalist ontology on the one hand, and its epistemology and creation account on the other, a picture will emerge as to what ought to constitute that ontology. This picture will allow us to identify a substantial burden of proof for alternative naturalist ontologies that bloat naturalist metaphysical commitments beyond what is justifi able within the constraints that follow from the other two aspects of a naturalist worldview.
1. Graham Oppy offers a brief critique of AC, especially as formulated by John Locke and Richard Swinburne.
See Arguing about Gods (Oppy 2006, pp. 382–401). Unfortunately, he rejects all-too-briefl y cumulative case arguments (Oppy 2006, pp. 5–6) and, thus, in my view does not give them suffi cient consideration.
Naturalism is the view that the spatiotemporal universe of entities postulated by our best current (or ideal) theories in the physical sciences, particularly physics, is all there is.
It includes (1) a naturalist epistemic attitude (e.g. a rejection of so-called fi rst philosophy); (2) an etiological account of how all entities whatsoever have come to be, constituted by an event-causal story described in natural scientifi c terms; and (3) a general ontology in which the only entities allowed are ones that bear a relevant similarity to those thought to characterize a completed form of physics. Whether this ontology should also include sui generis emergent properties will occupy our attention shortly.
The ordering of these is important. The epistemic attitude justifi es the etiology, which together justify the ontological commitment. Also, naturalism requires coherence among these three areas. David Papineau claims that we should set philosophy within science in that philosophical investigation should be conducted within the framework of our best empirical theories. It follows that “… the task of the philosophers is to bring coherence and order to the set of assumptions we use to explain the empirical world” (Papineau 1993, p.3). Thus, there should be coherence among third-person scientifi c ways of knowing, a physical, evolutionary account of how our sensory/cognitive processes came to be, and an analysis of those processes themselves. Any entities that are taken to exist should bear a relevant similarity to those characterizing our best (or ideal) physical theories, their coming-to-be should be intelligible in light of the naturalist causal story, and they should be knowable by scientifi c means.
The naturalist epistemic attitude
Scientism constitutes the core of the naturalist epistemology. Wilfrid Sellars said that “in the dimension of describing and explaining the world, science is the measure of all things, of what is that it is, and of what is not that it is not” (Sellars 1963, p.173). Contemporary naturalists embrace either weak or strong scientism. According to the former, nonscientifi c fi elds are not worthless nor do they offer no intellectual results, but they are vastly inferior to science in their epistemic standing and do not merit full credence. According to the latter, unqualifi ed cognitive value resides in science and in nothing else. Either way, naturalists are extremely skeptical of any claims about reality that are not justifi ed by scientifi c methodology in the hard sciences.
For example, that methodology is a third-person one that sanctions only entities capable of exhaustive description from a third-person perspective. Skepticism prevails for entities that require the fi rst-person perspective as their basic mode of epistemic access. For such naturalists, the exhaustive or elevated nature of scientifi c knowledge entails that either the only explanations that count or the ones with superior, unqualifi ed acceptance are those employed in the hard sciences.2 At least two philosophical theses elaborate the naturalistic epistemic and methodological constraints for philosophy. First, there is no such thing as fi rst philosophy; rather, there is continuity between philosophy and natural science. Second, scientifi c theories that are paradigm cases of epistemic/explanatory success, for example, the atomic theory of matter, evolutionary biology, employ combinatorial modes of explanation. Thus, any process that constitutes the Grand Story and any entity in the naturalist ontology should exhibit an ontological structure analyzable in terms that are isomorphic 2. I am assuming here a realist construal of explanation.
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with such modes of explanation. Colin McGinn has defended this idea along with what he takes it to entail, viz., the inability of naturalism to explain genuinely unique emergent properties:
Can we gain any deeper insight into what makes the problem of consciousness run against the grain of our thinking? Are our modes of theorizing about the world of the wrong shape to extend to the nature of mind? I think we can discern a characteristic structure possessed by successful scientifi c theories, a structure that is unsuitable for explaining consciousness. . . .
Perhaps the most basic aspect of thought is the operation of combination. This is the way in which we think of complex entities as resulting from the arrangement of simpler parts.
There are three aspects to this basic idea: the atoms we start with, the laws we use to combine them, and the resulting complexes . . . I think it is clear that this mode of understanding is central . . . [and] our scientifi c faculty involves representing the world in this combinatorial style. (McGinn 1999, pp.55–6; cf. pp.54–62, 90, 95)
The naturalist Grand Story
Let us call the naturalist creation account “the Grand Story”: All of reality – space, time, and matter – came from the Big Bang and various heavenly bodies developed as the universe expanded. On at least the Earth, some sort of prebiotic soup scenario explains how living things came into being from nonliving chemicals. And the processes of evolution, understood in either neo-Darwinian or punctuated equilibrium terms, gave rise to all the life forms we see including human beings. Thus, all organisms and their parts exist and are what they are because they contributed to (or at least did not hinder) the struggle for reproductive advantage, more specifi cally, because they contributed to the tasks of feeding, fi ghting, fl eeing, and reproducing.
The Grand Story has three key features. First, at its core are two theories that result from combinatorial modes of explanation: the atomic theory of matter and evolutionary theory.
If we take John Searle to be representative of naturalists here, this means that causal explanations, specifi cally, bottom-up but not top-down causal explanations, are central to the (alleged) explanatory superiority of the Grand Story (Searle 1994, p.83–93).
Second, it expresses a scientistic philosophical monism, according to which everything that exists or happens in the world is susceptible to explanations by natural scientifi c methods. Prima facie, the most consistent way to understand naturalism in this regard is to see it as entailing some version of strong physicalism: everything that exists is fundamentally matter, most likely, elementary “particles” (whether taken as points of potentiality, centers of mass/energy, units of spatially extended stuff/waves, or reduced to/eliminated in favor of fi elds), organized in various ways according to the laws of nature. By keeping track of these particles and their physical traits, we are keeping track of everything that exists.
No nonphysical entities exist, including emergent ones. When naturalists venture away from strong physicalism, however, they still argue that additions to a strong physicalist ontology must be depicted as rooted in, emergent from, and dependent on the physical states and events of the Grand Story.
Third, the Grand Story is constituted by event causality and eschews both irreducible teleology and agent causation (AGC) in which the fi rst relatum of the causal relation is in the category of substance and not event. And the Grand Story is deterministic in two senses:
diachronically, such that the state of the universe at any time t coupled with the laws of nature determine or fi x the chances for the state of the universe at subsequent times; and synchronically, such that the features of and changes regarding macrowholes are dependent on and determined by microphenomena.
The naturalist ontology
Weak versus strong naturalism
There is a distinction between strong/strict and weak naturalists. Strong naturalists (e.g.
Papineau) accept a strict version of physicalism (all individuals, events, states of affairs, properties, relations, and laws are entirely physical) for the natural world, while weak naturalists (e.g. Searle) embrace various emergent entities.
The location problem
A good place to start a more detailed analysis of a naturalist ontology is with what Frank Jackson calls the location problem (Jackson 1998, pp. 1–5). On the basis of the superiority of the naturalist epistemology, naturalists accept a fairly widely accepted physical story about how things came to be (the Grand Story) and what they are. The location problem is the task of locating some entity (e.g. semantic contents) in that story.
For Jackson, the naturalist must either locate a problematic entity in the basic story or eliminate it. Roughly, an entity is located in the basic story just in case it is entailed by that story. Otherwise, the entity must be eliminated. At this point, it is worth recalling that Kim and others have complained that one does not explain a phenomenon by labeling it supervenient. Likewise, one might think that someone has not really “located” a puzzling phenomena if all one has done is point out that it necessarily covaries with this or that sort of physical phenomenon. In any case, Jackson provides three examples of location. First, just as density is a different property from mass and volume, it is not an additional feature of reality over and above mass and volume in at least this sense: an account of things in terms of mass and volume implicitly contains, that is, entails the account in terms of density.
Second, Jones’s being taller than Smith is not an additional feature of reality besides Jones’s and Smith’s heights because the relational fact is entailed, and in this sense located by the latter.
More importantly, Jackson focuses on the location of macrosolidity. He acknowledges that prior to modern science, there was a widely accepted commonsense notion of macrosolidity, viz., being everywhere dense. However, due to modern science, this notion has been replaced with being impenetrable. Thus, macrosolidity may be located in the basic microstory: given a description of two macro-objects in terms of their atomic parts, lattice structures, and subatomic forces of repulsion, this description entails that one macro-object is impenetrable with respect to the other.
Jackson believes mental properties are troublesome entities for the naturalist to locate, and the naturalist must argue that they globally supervene on the physical. He unpacks this claim with two clarifi cations. First, he defi nes a minimal physical duplicate of our world as “a world that (a) is exactly like our world in every physical respect (instantiated property for instantiated property, law for law, relation for relation), and (b) contains nothing else in the sense of nothing more by way of kinds or particulars than it must to satisfy (a)”
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(Jackson 1998, p. 13). Second, he advocates B*: any world that is a minimal physical duplicate of our world is a psychological duplicate of our world.
The logic of the mereological hierarchy
Jackson correctly grasps the connection between accepting the epistemic superiority of naturalism and deciding between weak and strong naturalism. For Jackson, if naturalism is to have superior explanatory power, this entails strong naturalism. Jackson understands that there are at least three constraints for developing a naturalist ontology and locating entities within it: (a) entities should conform to the naturalist epistemology; (b) entities should conform to the naturalist Grand Story; (c) entities should bear a relevant similarity to those found in chemistry and physics or merely be capable of one-to-one or one-to-many correlation with entities in chemistry or physics or be shown to depend necessarily on entities in chemistry and physics.
Further in the discussion, we will see why these constraints disallow explanations for the existence of emergent properties. Regarding emergent properties, the second disjunct of (c) “solves” the so-called explanatory gap by simply naming the problem and dismissing the need for a naturalist to do any further explanatory work. For many philosophers, including many naturalists, this strategy is inadequate. The second disjunct also suffers from the diffi culty of justifying the existence of sui generis emergent entities in light of criteria (a) and (b). The third disjunct of (c) suffers from this latter problem and also from diffi culties with justifying the claim that emergent entities are “necessitated” by their subvenient physical bases. Defending these claims are central to the desiderata of this chapter.
But it may be useful at this stage of refl ection to show how (a) and (b) justify the standard mereological hierarchy as the proper naturalist ontology.
Construing the hierarchy in terms of individual entities and properties rather than in terms of concepts or linguistic descriptions, it consists in an ascending level of entities in the category of individual such that for each level above the ground level of elementary microphysics (at which entities have no further physically signifi cant separable parts), wholes at that level are composed of the separable parts at lower levels. Thus, from bottom to top we get microphysical entities, subatomic parts, atoms, molecules, cells, living organisms, and so on. The relationship between individuals at level n and n + 1 is the part/whole relation.
Here is a key point about the hierarchy in the category of individual and property (see further discussion): the “hierarchy” is not really a hierarchy. There is no ascending anything.
Rather, the levels form spatiotemporally wider and wider wholes. So we should think of the “hierarchy” as going out, not up.
Moreover, there are ontological constraints for what sorts of properties a naturalist should include in the hierarchy. As typically presented, the hierarchy entails the causal closure of the basic microphysical level along with the ontological dependence of entities and their activities at supervenient levels on entities and their activities at that basic level.
Causal closure and top/down causation are controversial. But acceptance of closure and a rejection of top/down causation are hard for a naturalist to avoid. The basic naturalist argument for causal closure is that if it is rejected, then
you are ipso facto rejecting the in-principle completeability of physics—that is, the possibility of a complete and comprehensive physical theory of all physical phenomena. For you would
be saying that any complete explanatory theory of the physical domain must invoke nonphysical causal agents. . . . It is safe to assume that no serious physicalist could accept such a prospect. (Kim 1998, p. 40)
The completeability of physics is not arbitrary. It follows naturally from the Grand Story, according to which one begins at the Big Bang with a small number of physical entities and explains the origin and behavior of everything else in terms of the laws of physics and new combinations of microphysical entities. The Story itself gives pride of place to microphysical entities and it is bottom/up at its core. The completeability of physics is essential to the explanatory superiority of the Story. The causal closure principle (no physical event has a nonphysical cause) is not arbitrary nor is it an additional postulate naturalists are intellectually free to reject. It follows from the combinatorial mode of causal explanation and the Grand Story’s commitment to the sort of micro-macro constitution and deter mination at the core of the atomic theory of matter, evolutionary biology, and other central theories of how things have come to be. If a naturalist rejects closure, he or she will have to accept sui generis, contingent brute facts. In turn, this undermines the claim that a naturalist worldview is superior to rivals because it can explain how all things have come to be.
Besides closure, a related issue for deciding what sorts or properties should populate the hierarchy is the problem of top/down causation. There is severe intellectual pressure from naturalism itself for rejecting top/down causation for genuinely emergent sui generis properties. Moreover, the only way to save top/down causation is to reduce it to outside/in causation that occurs with respect to structural wholes at the same level as their parts via causal feedback. I also think that the price to be paid for retaining causal laws in the special sciences is to disallow emergent properties and allow only microphysically based structural properties constituted by microphysical parts, properties, and relationships. If this is right, it follows that an adequate treatment of these desiderata (to preserve “top/down” causation and causal laws in the special sciences) entails that a naturalist ontology constituted by the standard mereological hierarchy can countenance structural wholes in the category of individual and structural supervenient properties in the category of property, but it cannot countenance genuine emergent properties, especially causally active emergent properties.
All emergent properties, if such there be, must be epiphenomenal.
An emergent property is a completely unique, new kind of property different from those that characterize its subvenient base. Accordingly, emergent supervenience is the view that the supervenient property is a simple, intrinsically characterizable, novel property different from and not composed of the parts, properties, relations, and events at the subvenient level. We may characterize “novel” as follows:
Property P is a novel emergent property of some particular x at level ln just in case P is an emergent property, x exemplifi es P, and there are no determinates P’ of the same determinable D as P such that some particular at level li=1−(n−1) exemplifi es P or P’. (Haldane 1996) A structural property is one that is constituted by the parts, properties, relations, and events at the subvenient level. A structural property is identical to a confi gurational pattern among the subvenient entities. It is not sui generis.
The existence of emergent mental properties presents two problems for naturalism.
First, for those who accept a causal criterion of existence, emergent mental properties are
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epiphenomenal and, thus, do not exist. One is then faced with a dilemma: accept phenomenal consciousness as emergent and reject causal closure or retain closure and reject phenomenal consciousness on the grounds that it is epiphenomenal. In the subsequent sections, we shall examine versions of naturalism that accept emergent mental properties. These versions must address epiphenomenalism.
Second, it is pretty obvious that mental states are causal factors in our behavior. Knowledge and agency are hard to salvage if this is denied. Indeed, if an analysis of mental states entails epiphenomenalism, this is widely recognized as fodder for a reductio against that analysis. Thus, many naturalists think that the only way to save mental causation is to identify it with the physical. Not all naturalists reject top/down causation. But since bottom/
up but not top/down causation follows most naturally from (1) the central theories that constitute the Grand Story and (2) the mereological hierarchy with the dependency of lower on higher levels, there is a burden of proof on those naturalists who accept genuine top/down (and not merely outside/in) causation.
Here is one fi nal constraint for a naturalist ontology. If we limit ourselves to macroproperties, an appropriate limitation because consciousness is a macrofeature, then the following principle seems to be prima facie justifi ed:
Principle of Naturalist Exemplifi cation (PNE): (x) Px → Ex
P stands for any property whatever and E stands for the property of being extended. Moreover, x ranges over and only over property instances. Elsewhere I have defended a constituent ontology in which property instances are complex entities, and I shall merely assume this ontology here (see Moreland 2001b). According to this ontology, when some concrete particular e exemplifi es a property P, then the-having-of-P-by-e is a property instance that is modally distinct from both P and e. Thus, x is neither identical to P nor e. So understood, property instances are certain sorts of states of affairs and, moreover, if the instantiation of P by e is temporal, then the property instance becomes an event.
Note that P and e are constituents of x. If we focus on paradigm cases that satisfy PNE, it becomes reasonable to hold that the spatial extension of x is grounded in, obtains in virtue of the spatial extension of e. For example, when an apple is red, the-having-of-red-by-the-apple is a property instance spread out through the extended region occupied by the apple. It is in virtue of the apple’s extension that the particular instance of red is extended. This may be seen, for example, by noting that it is because the apple has a particular shape that its instance of red has that shape as well.
PNE says that if a property in the naturalist ontology is to be exemplifi ed, then a necessary condition is that both the concrete particular that exemplifi es P and the property instance that results have spatial extension.
PNE seems to capture nicely the wide range of properties in macrophysics, chemistry, geology, neuroscience, and so forth. It could be objected that PNE fails because certain entities, for example, some quantum entities or the point particles of Roger Boscovich were unextended and provide counterexamples to PNE. I do not think this objection works. Regarding quantum entities, there are at least eight different empirically equivalent philosophical models of quantum reality and, it is irresponsible to make dogmatic claims about the ontology of the quantum level (Herbert 1987, p. 15–29). And since I have limited PNE to the macrolevel, we may set aside the quantum world for our purposes. Regarding entities such as Boscovich’s particles, rather than conclude that they are counterexamples
to PNE, their lack of spatial dimensionality may be taken as a reductio against them. Indeed, this is how the history of physics ran. Boscovichian particles fi t more easily into a spiritual-ist ontology (e.g. Berkeley’s) than in a straightforward version of materialism, and like action at a distance, they were rejected.
There is a debate about whether individual mental states such as pains and thoughts are extended. I cannot enter that debate here. But on the basis of PNE, if it turns out that mental states are not extended, then PNE banishes them and their constituent properties from a naturalist ontology. In this case, PNE counts against any naturalist ontology that quantifi es over emergent mental properties.
It is time to summarize what a naturalist ontology should look like (cf. Moreland 1998b). In the category of individual, if we reject an eliminativist strategy, then all wholes
“above” the microphysical level are structural, relational entities constituted by the parts, properties, and relations at the microphysical level. Such wholes stand in a constituent/
whole relation to these microphysical entities and are actually wider entities at the basic level. Regarding the category of property, consider the following:
Emergence0: new features that can be deduced from base (e.g. fractals)
Emergence1: ordinary structural properties (e.g. being water, solidity)
Emergence2a: sui generis, simple, intrinsically characterizable, new kinds of properties relative to base that are also epiphenomenal (e.g. being painful construed epiphenomenally) Emergence2b: sui generis, simple, intrinsically characterizable, new kinds of properties relative to base with new causal powers construed as passive liabilities (e.g. being painful understood as having top/down causal liabilities)
Emergence2c: sui generis, simple, intrinsically characterizable, new kinds of properties with active power
Emergence3: an emergent, suitably unifi ed mental ego with active power
Clearly, Emergence0 and Emergence1 fi t nicely in the mereological hierarchy and conform to the naturalist epistemology (e.g. combinatorial explanation) and Grand Story. But Emergence2a through Emergence3 should be disallowed for reasons we have already investigated. It would seem that all a naturalist could do with them is simply to label them as contingent brute facts and assert that they are not a problem for the naturalist. We will look at different attempts to handle some of these sorts of properties in subsequent sections. But we have already examined reasons to be highly suspicious of a naturalist view that accepts one or more of these sorts of properties and also claims that naturalism is explanatorily and epistemically superior to alternative worldviews.
Moreover, there is an increasingly heavy burden of proof on a naturalist ontology as one moves from Emergence2a to Emergence3. All types of emergence fall prey to previous arguments against emergent entities. Emergence2a requires less justifi cation than stronger forms of emergence because it does not require a rejection of closure. Emergence2b is subject to these arguments and additional diffi culties with top/down causation and causal closure. But relative to Emergence2c and Emergence3, it has the advantage of exhibiting the same sort of causal power – passive liability subject to law – that characterizes causal particulars at the microphysical level.
Emergence2c has all the problems exemplifi ed by Emergence2b and it also suffers from having a unique sort of active causal power different from causal powers of the naturalist ontology besides agent-causal events. Emergence3 shares diffi culties with Emergence2c and
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it also suffers from two further facts not easily accommodated in the naturalist ontology if they are taken as irreducible and uneliminable facts about the world: the indexical fact associated with “I” and diffi culties with explaining how one can get a sort of primitive, substantial unity in which its various inseparable parts/faculties are internally related to the substantial subject from a mereological aggregate constituted by a structural arrangement of separable parts that stand in external relations to each other and their mereological whole.
Serious metaphysics, simplicity, and emergent properties
Frank Jackson begins his attempt to develop a naturalistic account of the mental by contrasting two very different approaches to metaphysics. The fi rst he calls serious metaphysics. Serious metaphysics is not content to draw up large pluralistic lists of sui generis entities. Advocates of serious metaphysics tend to approach the discipline with a prior epistemic commitment of some sort which functions as a criterion of knowledge or justifi ed belief for quantifying over some entity. Thus, naturalist commitment to serious metaphysics usually includes epistemological methodism constituted by the naturalist epistemic attitude. Accordingly, serious metaphysics is primarily explanatory and not descriptive metaphysics. Thus, advocates seek to account for all entities in terms of a limited number of basic entities and in this way serious metaphysics is inherently reductionistic.
For naturalists, these entities will constitute those at the core of the Grand Story: A property /event/object x exists iff it is contained within (truth functionally entailed by) the Grand Story.
The second perspective we may call a “shopping-list” approach whose primary goal is a careful description and categorial analysis of reality. Advocates usually employ epistemological particularism, and it is no accident that Roderick Chisholm is the paradigm case of epistemological particularism and shopping-list metaphysics (cf. Chisholm 1989a,b, pp. 162–8).
Jackson correctly claims that the scientifi c naturalist will prefer serious metaphysics. His naturalist approach to metaphysics expresses a certain form of the principle of simplicity and provides material content for that principle of simplicity most suited for a philosophical naturalist. To see this, let us compare two versions of the principle of simplicity, an epistemic and ontological version, respectively:
SimplicityE: entities must not be multiplied beyond necessity
SimplicityO: our ontology/preferred theory about the world should be simple
Of course, there are various ways to state each principle, but these will do for our purposes. SimplicityE may not be easy to apply (one rival may be simple in one respect and the other in a different respect; one rival may be simpler and the other may be more empirically accurate), but its rationale is fairly straightforward. All things being equal, if a simpler theory does the epistemic job, then the more complicated theory has baggage that serves no important epistemic function. Ontological simplicity is quite different from epistemic simplicity, and some philosophers confl ate the two principles. For example, Kim rightly advocates epistemological simplicity for the same reason just mentioned. But he then passes over into ontological simplicity, apparently without noticing the equivocation. After embracing “entities must not be multiplied beyond necessity,” he urges with no justifi cation
or further explanation that “we expect our basic laws to be reasonably simple, and we expect to explain complex phenomena by combining and iteratively applying these simple laws”
(Kim 1996, p. 91).
Ontological simplicity does not follow from epistemic simplicity. In fact, it sometimes happens that progress in an area of science entails adopting a more complicated ontology even though both the simpler and more complicated ontologies are epistemically simple.
The shift from the simpler ideal gas equation to the more complicated van der Waals equation is a case in point. That said, I believe that the naturalist should adopt both principles of simplicity, and Kim and Jackson give the reason why. Each makes reference to the Grand Story (which, in turn, is justifi ed by the naturalist epistemology), which is inherently reductionistic.
Moreover, if naturalists claim to have epistemic/explanatory superiority over rivals, then their employment of the Grand Story must be done such that entities that cannot be identifi ed with some structural combination of fundamental microphysical entities must be eliminated. Kim and Jackson both understand this, and while Jackson seeks to carry out this way of understanding the location project, Kim has abandoned it in recent months (see Kim 2005, chap. 6; cf. 1998, chap. 4). Still, Kim’s appeal to ontological simplicity ever bit as much as Jackson’s provides a representative naturalist employment of the principle.
And their characterization of it provides a way of transforming the merely formal principle SimplicityO into a related version with material content. For Kim, we begin with simple, basic laws – and presumably microphysical particulars governed by them – and allow more complex entities into one’s ontology only if they are subject to combinatorial modes of explanation that involve the iterative application of the basic laws. Similarly, Jackson says one should start with the Grand Story and allow entities into one’s ontology only if they are entailed by that ontology (Jackson 1998, pp. 24–7).3 For Jackson, this means accepting only structural entities that are Emergence0 or Emergence1. Expressed in terms of the appropriate naturalist material principle of simplicity, we have
SimplicityON: our ontology or preferred theory about the world should be simple in the sense that it contains the microphysical entities of an ideal physics or entities whose existence can be explained by the naturalist epistemology (e.g. combinatorial modes of explanation) applied to the microphysical entities that constitute the Grand Story.
SimplicityON would seem to rule out entities that are Emergence2 or Emergence3.
A realist view of causation and emergent properties
We have seen reasons for adopting a prima facie burden of proof on any naturalist ontology that includes emergent entities. If such entities are accepted, then a naturalist would owe us a causal account of their coming-to-be. In closing this section, it is important to state 3. By “entails” here, Jackson means the ordinary truth-functional connective. Jackson actually thinks physicalism a priori entails the psychological and that this is a necessary truth. If physicalism ϕ is true, then, of necessity, the psychological truths ψ follow a priori. Jackson employs a version of two-dimensional semantics to defend the claim that instances of ϕ → ψ are a priori necessary. But this is a stronger claim and many naturalists would not follow him in this, so I shall employ the weaker truth-functional version in what follows. I am indebted to Shaun McNaughton for pointing this out to me.
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certain constraints on such an account. In the sections to follow, we shall look at naturalist views that seek to conform to or disregard these constraints. But these constrains seem prima facie justifi ed because they follow naturally from the naturalist epistemology, Grand Story, and other aspects of the naturalist ontology.
Regarding emergent properties, although some demur, at least fi ve reasons have been proffered for the claim that causal explanations in the natural sciences exhibit a kind of causal necessity, that on a typical realist construal of natural science, physical causal explanations must show – usually by citing a mechanism – why an effect must follow given the relevant causal conditions:
(1) Causal necessitation unpacks the deepest, core realist notion of causation, namely, causal production: a cause “brings about” or “produces” its effect.
(2) Causal
necessitation
fi ts the paradigm cases of causal explanation central to the core
theories that constitute a naturalist worldview and in terms of which it is purported to have explanatory superiority to rival worldviews.
(3) Causal necessitation provides a way of distinguishing accidental generalizations or coincidences from true causal laws or sequences.
(4) Causal necessitation grounds the derivation of counterfactuals.
(5) Causal necessitation clarifi es the direction of causality.
Three points of clarifi cation are in order. First, minimally, the sort of modality involved may be taken as physical necessity, a form of necessity that runs throughout possible worlds relevantly physically similar to our actual world (e.g. in having the same physical particulars, properties, relations, and/or laws). Second, strong conceivability is the test that is used to judge causal necessitation (given the lattice structures and so forth of two macro-objects impenetrable with respect to each other, it is strongly inconceivable that one could penetrate the other).
Finally, Principles (3)–(5) have sometimes been offered as additions to a covering law form of explanation to provide an adequate natural scientifi c causal explanation. Strictly speaking, a covering law “explanation” is just a description of what needs to be explained and not an explanation. But by adding a causal model that underwrites it and that exhibits causal necessitation, the total package provides explanations for both what and why the phenomena are as they are. For brevity’s sake, I will talk as if a covering law explanation is an explanation, but when I speak of a covering law explanation I mean to include in it an underwriting causal model.
In this section, we have examined the limitations on a naturalist ontology that follow from naturalism itself taken as a worldview epistemically/explanatorially superior to its rivals. Let N stand for the truth of naturalism. In the terms of epistemic appraisal proffered by Chisholm, it seems that – (N & Emergence2a) is at least epistemically in the clear where a proposition is epistemically in the clear provided only that subject S is not more justifi ed in withholding that proposition than in believing it. Alternatively, it is at least reasonable to disbelieve (N & Emergence2a) (S is not more justifi ed in withholding that proposition than in disbelieving it) (Chisholm 1977, p. 16).
However, there are additional limits for a naturalist ontology when a plausible rival worldview is brought into the picture. As Timothy O’Connor points out, emergent properties, especially mental properties, must be shown to arise by way of causal necessitation from a microphysical base if we are to “render emergent phenomena naturalistically
explicable” (O’Connor 2000, p. 112). Among his reasons is the idea that if the link between microbase and emergent properties is a contingent one, then the only explanation for the existence and constancy of the link is a theist explanation (O’Connor 2000, pp. 70–1, n. 8).
O’Connor claim seems to me to be correct, and to probe this matter further, we turn to an examination of the theistic argument for God’s existence from consciousness.
Section Two: The AC
In this section, I shall clarify and defend this AC by describing three issues in scientifi c theory acceptance relevant to assessing AC’s force, presenting three forms of AC and offering a brief defense of its premises. I hope to show that an important factor in theory acceptance – scientifi c or otherwise – is whether or not a specifi c theory has a rival. If not, then certain epistemic activities, for example, labeling some phenomenon as basic for which only a description and not an explanation is needed, may be quite adequate not to impede the theory in question. But the adequacy of those same activities can change dramatically if there is a suffi cient rival. Section one presented reasons for denying emergent mental properties/events that follow solely from naturalism. In this section, we shall discover additional reasons for naturalists to eschew emergent mental entities that follow because of the presence of AC. The combined force of sections one and two place a severe (and increasing) burden of proof on any naturalist who seeks to reconcile the existence of emergent mental entities (from Emergence2a to Emergence3) with naturalism.
Three issues in scientifi c theory acceptance
Basicality
While theism and naturalism are broad worldviews and not scientifi c theories, three issues that inform the adjudication between rival scientifi c theories are relevant to AC. The fi rst issue involves deciding whether it is appropriate to take some phenomenon as basic such that only a description and not an explanation for it is required, or whether that phenomenon should be understood as something to be explained in terms of more basic phenomena. Attempts to explain uniform inertial motion are disallowed in Newtonian mechanics because such motion is basic on this view, but an Aristotelian had to explain why a particular body exhibited uniform inertial motion. Thus, what is basic to one theory may be derivative in another.
Naturalness
Issue two is the naturalness of a postulated entity in light of the overall theory of which it is a part. The particulars, properties, and relations postulated should be at home with other entities in the theory and, in this sense, be natural for the theory. Some entity (particular thing, process, property, or relation) e is natural for a theory T just in case either e is a central, core entity of T or e bears a relevant similarity to central, core entities in e’s category within T. If e is in a category such as substance, force, property, event, relation, or cause, e should bear a relevant similarity to other entities of T in that category. This is a formal defi nition and the material content given to it will depend on the theory in question. In
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section one, I argued that the basic entities constituitive of the Grand Story provide the material content for naturalism.
Moreover, given rivals R and S, the postulation of e in R is ad hoc and question-begging against advocates of S if e bears a relevant similarity to the appropriate entities in S, and in this sense is “at home” in S, but fails to bear this similarity to the appropriate entities in R. The notion of “being ad hoc” is diffi cult to specify precisely. It is usually characterized as an inappropriate adjustment of a theory whose sole epistemic justifi cation is to save the theory from falsifi cation. Such an adjustment involves adding a new supposition to a theory not already implied by its other features. In the context of evaluating rivals R and S, the principle just mentioned provides a suffi cient condition for the postulation of e to be ad hoc and question-begging.
Naturalness provides a criterion for advocates of a theory to claim that their rivals have begged the question or adjusted their theory in an inappropriate, ad hoc way. Naturalness is also useful for deciding the merits of accepting R, which depicts phenomenon e as basic, versus embracing S, which takes e to be explainable in more basic terms. If e is natural in S but not in R, it will be diffi cult for advocates of R to justify the bald assertion that e is basic in R and that all proponents of R need to do is describe e and correlate it with other phenomena in R as opposed to explaining e. Such a claim by advocates of R will be even more problematic if S provides an explanation for e.
Epistemic values
Issue three involves epistemic values, normative properties which confer some degree of justifi cation on a theory possessing them. Examples are theories should be simple, descriptively accurate, predicatively successful, fruitful for guiding new research, capable of solving their internal and external conceptual problems, and use certain types of explanations or follow certain methodological rules and not others (e.g. “appeal to effi cient and not fi nal causes”).
Studies in scientifi c theory assessment have made it clear that two rivals may solve a problem differently depending on the way each theory depicts the phenomenon to be solved.
It is possible for two rivals to rank the relative merits of epistemic values in different ways or even give the same virtue a different meaning or application. Rivals can differ radically about the nature, application, and relative importance of a particular epistemic value. Thus, in arguing against B, it may be inappropriate for advocates of A to cite its superior comportment with an epistemic value when B’s proponents do not weigh that value as heavily as they do a different one they take to be more central to B. For example, given rivals A and B, if A is simpler than B but B is more descriptively accurate than A, then it may be inappropriate – indeed, question-begging – for advocates of A to cite A’s simplicity as grounds for judging it superior to B. I am not suggesting that rivals are incommensurable. In fact, I believe that seldom, if ever, is this the case. Only on an issue-by-issue basis can one appropriately make judgments about the epistemic impact of the confl ict of disparate epistemic values.
The AC
The deductive form of the argument
Theists (e.g. Robert Adams (1992, pp. 225–40) and Richard Swinburne (1979, chap. 9; 1986, p. 183–96)) have advanced a different theistic argument from consciousness. The argument
may be construed as an inference to the best explanation, a Bayesian-style argument, or a straightforward deductive argument in which its premises are alleged to be more reasonable then their denials. Setting the inductive forms aside, AC becomes the following: (1) Mental events are genuine nonphysical mental entities that exist.
(2) Specifi c mental and physical event types are regularly correlated.
(3) There is an explanation for these correlations.
(4) Personal explanation is different from natural scientifi c explanation.
(5) The explanation for these correlations is either a personal or natural scientifi c explanation.
(6) The explanation is not a natural scientifi c one.
(7) Therefore, the explanation is a personal one.
(8) If the explanation is personal, then it is theistic.
(9) Therefore, the explanation is theistic.
Overview of deductive premises
In my view, Premises (3) and (6) are the most crucial ones for the success of AC, since they are the premises most likely to come under naturalist attack. Let us set them aside for the moment. We are assuming the truth of Premises (1) and (2). All the naturalist rivals of AC
we are considering agree with them.
The main justifi cation for Premise (4) is the difference between libertarian and event causal theories of agency. J. L. Mackie rejected (4), claiming that personal explanation is simply a subclass of event causal explanation. Moreover, divine action in Swinburne’s account of personal explanation involves the direct fulfi llment of an intention on the part of God. But, argued Mackie, since human action is a type of effi cient event causality between the relevant prior mental state, for example, an intending, and a fulfi llment which runs through and depends on a number of intermediate events which are part of a complex physical mechanism, there is a disanalogy between human intentional acts in which intentions are fulfi lled indirectly and those of a god in which, supposedly, intentions are directly fulfi lled. On Mackie’s view, this disanalogy makes alleged divine action and the relevant sort of personal explanation mysterious and antecedently improbable. Thus, (4) is false and, even if it is true, it makes theistic personal explanation less, not more probable.
Is Mackie’s argument successful against (4)? I do not think so. For one thing, pace Mackie, it is not at all clear that libertarian agency and the associated form of personal explanation are not to be preferred as accounts of human action to event-causal accounts.
Obviously, we cannot delve into this issue here, but if libertarian agency is correct, then Mackie is wrong in his claim that (4) is false.
Secondly, a defense of (4) may only require a concept of libertarian agency and personal explanation, even if we grant an event-causal theory of action for human acts. If we have such a clear conception, then even if human acts do not fall under it, under the right circumstances, it could be argued that a form of explanation clearly available to us is now to be employed. What those circumstances are and whether they obtain are more centrally related to Premises (3) and (6) of AC and not (4). But since Mackie criticized (4) on the grounds that if true it would make theistic explanation antecedently improbable, I want briefl y to say something about what could justify the claim that a personal explanation of the libertarian sort should actually be used.
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Many have tried to state necessary and suffi cient conditions for personal action in event-causal terms with John Bishop’s account being the most sophisticated to date. But Bishop admits that our concept of agency is different from and irreducible to event causality and is, in fact, libertarian (Bishop 1989, pp. 58, 72, 69, 95–6, 103–4, 110–1, 126–7, 140–1, 144).
For Bishop, the pervasiveness and power of the libertarian conception of agency places the burden of proof on the defender of a causal theory of action. Bishop claims that his own causal theory works only for worlds relevantly similar to ours in being naturalistic worlds.
He does not offer an analysis of action true across all possible worlds because he admits that our concept of action is libertarian and there are worlds in which it is satisfi ed. His justifi cation of this minimal task is a prior assumption of naturalism, but such an assumption is clearly question-begging against AC. So if we have a clear, powerful, and prima facie justifi ed libertarian conception of agency, Mackie’s point about the mysteriousness and antecedent improbability of anything answering to this concept is seriously overstated.
Granting the nonphysicality of mental states, a causal theory of personal action will boil down to the claim that person P does some act e (raising one’s hand to vote) if and only if some event b (the hand going up), which instantiates the type of state intrinsic to e-ing is caused by the appropriate mental state in the appropriate way. Note carefully that, regardless of the details of such an account, it will amount to nothing more that a causal correlation between certain physical states and the relevant mental events. According to Premises (2) and (3) of AC, these correlations need and have an explanation. A causal theory of action will not do for the origin, regularity, and precise nature of these correlations, since these are what constitute a causal theory of action in the fi rst place. If a causal theory of action presupposes mental states, then it will be impotent to explain the existence, regularity, and precise nature of those mental states themselves unless, of course, a divine causal theory of action is used. If this is so, and if we possess a clear concept of libertarian agency and personal explanation, then there is no good reason why a theist cannot use this type of explanation in this case.
However, a defender of (4) could deny a libertarian view of agency and personal explanation. After all, some Christian theists (e.g. certain Calvinists) employ a causal theory for divine action. One could argue that there is some difference between normal physical event causality and a causal theory of personal action. Minimally, the latter utilizes appropriately related mental states as parts of causal chains. Since (4) simply notes that there is a distinguishable difference between personal and natural scientifi c explanation, the alternative we are now considering may be all that AC needs to rebut Mackie. Bishop claims that for a naturalist causal theory of action must be combined with a strong physicalist theory of mental states (Bishop 1989, pp. 8, 43, 103). But setting this aside, since we are assuming the reality of mental states, Bishop’s physicalist rendition of the causal theory of action simply does not apply here and a suitable statement of the nature and role of mental states in a causal theory could be all that is needed to distinguish personal from natural scientifi c explanation according to (4).
The presence of personal explanation as a unique argument form means that when it comes to explaining emergent properties such as those constituitive of consciousness, one does not need to acquiesce with Samuel Alexander’s dictum that such properties are “to be accepted with the natural piety of the investigator.” Thus, it is more than curious to fi nd naturalists jump straightaway from the recognition that mental properties are genuinely emergent and incapable of naturalist explanation to the conclusion that we must take then as brute facts.
There are two sides to (5): is personal explanation different from natural scientifi c explanation and are there other explanations for the facts mentioned in (1) and (2) besides these two? We have already dealt with the fi rst question in conjunction with (4). Regarding question two, I think it is safe to say that, given the current intellectual climate, a personal theistic or a naturalistic explanation would exhaust at least the live, if not the logical, options. It is true that Thomas Nagel suggested that panpsychism may be necessary to explain the mental (Nagel 1986, pp. 49–53). But it is widely recognized that panpsychism has serious problems in its own right – for example, explaining what an incipient or protomental entity is or how the type of unity that appears to characterize the self could emerge from a mere system of parts standing together in various causal and spatiotemporal relations (cf. Moreland 2008, chap. 6). Moreover, panpsychism is arguably less reasonable than theism on other grounds, although I cannot pursue this point here. Further, it is not clear that panpsychism is an explanation of the phenomena in question. As Geoffrey Madell notes,
the sense that the mental and the physical are just inexplicably and gratuitously slapped together is hardly allayed by adopting . . . a panpsychist . . . view of the mind, for [it does not]
have an explanation to offer as to why or how mental properties cohere with physical. (Madell 1988, p. 3)
For these and other reasons, I shall not consider panpsychism further except as part of Timothy O’Connor’s project.
Premise (7) follows from previous steps in the argument and asserts the adequacy of a personal explanation for the facts expressed in (1) and (2). One may reject (7) (or (5)) on the grounds that personal explanation, theistic or otherwise, does not give us any real understanding of an explanandum, especially one like (1) and (2). Sometimes this objection assumes that an explanation must cite a mechanism before it can count as adequate.
My response to this problem centers on the difference between libertarian and event causality and their associated forms of explanation.
Advocates of libertarian agency widely employ the following form of personal explanation (that stands in contrast to a covering law model): A personal explanation (divine or otherwise) of some basic result R brought about intentionally by person P where this bringing about of R is a basic action A will cite the intention I of P that R occur and the basic power B that P exercised to bring about R. P, I, and B provide a personal explanation of R: agent P brought about R by exercising power B in order to realize intention I as an irreducibly teleological goal.
By way of application, the adequacy of a personal explanation does not consist in offering a mechanism, but rather, in correctly citing the relevant person, his intentions, the basic power exercised, and in some cases, offering a description of the relevant action plan. Thus, if we have some model of God and His intentions for creating a world suitable for human persons (from revelation or otherwise), we can make reference to God, His intentions for creating a world with persons with mental states regularly correlated with their environment, and the adequacy of His power to bring about the basic results captured in (1) and (2).
Premise (8) seems fairly uncontroversial. Humean style arguments about the type, size, and number of deities involved could be raised, but these issues would be intramural theistic problems of small comfort to someone committed to naturalism (cf. Martin 1990,
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p. 220). And if we take live options only, then it seems fair to limit our alternatives in (5) to theistic or naturalistic. If that is acceptable, at least for the purposes of arguing against Searle and other naturalists like him, then (8) should not be objectionable.
In the terms of epistemic appraisal proffered by Chisholm, it seems that, given AC and what we have seen about the naturalist ontology from section one, – (N & Emergence2a) is at least beyond reasonable doubt where a proposition is beyond reasonable doubt for a subject S means that S is more justifi ed in believing that proposition than in withholding it. Alternatively, given AC, (N & Emergence2a) is at least reasonable to disbelieve (S is more justifi ed in disbelieving that proposition than in withholding it) (Chisholm 1989a, pp. 10–7).
However, it would be premature to conclude that this is the correct epistemic appraisal of (N & Emergence2a). We still need to look at Premises (3) and (6). Rather than doing so directly, I shall examine them in sections three through fi ve in the context of naturalist attempts that, if successful, would defeat (3) and (6).
Preview of sections three through fi ve
We have seen reasons that follow from the nature of naturalism itself and from the presence of AC as a rival for why a naturalist ought to be a strong physicalist. Unfortunately, strong physicalism is a tough sell, and a growing number of philosophers are dissatisfi ed with it.
Perhaps our conclusion that a naturalist ought to be a strong physicalist is premature.
Maybe there are adequate naturalist accounts of the mental. In sections three through fi ve, we will look at representative samples of the major strategies employed to provide such an account. I will conclude that none of these solutions is adequate and that AC is to be preferred. If I am right about this, then the existence of fi nite mental states provides good evidence that God exists. The best thing for a naturalist to do in this case it to opt for a strong form of physicalism.
Section Three: John Searle and Contingent Correlation
The weakest position for a naturalist who accepts emergent mental properties and events is one according to which all the naturalist must do adequately to explain the mental is to establish contingent correlations between physical and mental states and leave it at that.
Searle’s view is the most prominent attempt to fl esh out this approach.
Searle’s position
Contingent correlation
Actually, Searle acknowledges that correlations are not enough and an adequate account should include the transformation of correlations into causal relations by showing that the manipulation of the physical state alters the mental state and by providing a mechanism as to how this works. But for three reasons, I believe it is appropriate to take him as an example of a contingent correlation position. First, he takes such correlations to be adequate to justify the superiority of biological naturalism, so they are suffi cient conditions for a naturalist account of consciousness. Second, he claims that a causal explanation
of consciousness may be, in principle, beyond our abilities to obtain; even so, biological naturalism remains standing. Third, he argues against the need for a naturalist to meet some necessitation requirement, according to which one can show that the relevant mental state must occur given a certain physical state. That leaves us with correlations for which the establishment of counterfactual covariance would be nice but not necessary for biological naturalism to be adequate.
Biological naturalism
Searle says harsh things about the last 50 years or so of work in the philosophy of mind (Searle 1994, chaps. 1 and 2; cf. Burge 1992).4 He says that the fi eld has contained numerous assertions that are obviously false and has cycled neurotically through various positions because of the dominance of strong physicalism as the only option for a naturalist. For these naturalists, if one abandons strong physicalism one has rejected a scientifi c naturalist approach to the mind/body problem and opened himself up to the intrusion of religious concepts and arguments about the mental such as AC.
Searle offers his analysis of the mind as a naturalistic account because, he says, no one in the modern world can deny “. . . the obvious facts of physics–for example, that the world is made up entirely of physical particles in fi elds of force …” (Searle 1994, p. 28). Naturalism is constituted by the atomic theory of matter and evolutionary biology both of which allow for micro-to-micro or micro-to-macro causal explanations, but not macro-to-micro ones. Dualism in any form is widely rejected because it is correctly considered to be inconsistent with the scientifi c worldview. People educated in the scientifi c worldview know how the world works, and the existence of God is no longer a serious candidate for truth. But a commitment to naturalism and a concomitant rejection of dualism have blinded people to the point that they feel compelled to reject what is obvious to experience, namely, the obvious nature of consciousness and intentionality.
Searle’s own solution to the mind/body problem is biological naturalism: consciousness, intentionality, and mental states, in general, are emergent biological states and processes that supervene upon a suitably structured, functioning brain. Brain processes cause mental processes that are not reducible to the former. Consciousness is just an ordinary (i.e. physical) feature of the brain and, as such, is merely an ordinary feature of the natural world. Despite the frequent assertions by a number of philosophers that Searle is a property dualist, he denies the charge and seems puzzled by it. However, in my view, Searle is indeed a property dualist and an epiphenomenalist one at that, although he also denies the latter charge as well. To show this, let us consider the charge of property dualism fi rst. Searle’s characterization of neurophysiological and mental states are exactly those of the property dualist who insists that mental and physical properties are to be characterized in a certain way and that they are two, different types of properties. In light of Searle’s descriptions of the mental and physical, it is obvious why most philosophers charge him with property dualism, and the burden of proof is on him to show why he is not.
4. Since the publication of The Rediscovery of the Mind, Searle has restated his views on these topics, but he continues to cite this earlier work as his most thorough treatment on the topic from which he has not deviated. See his works The Mystery of Consciousness (1995, p. 194) and Mind (2004, p. 2). Thus, I will rely on The Rediscovery of the Mind in explicating Searle’s views and supplement them when needed.
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Searle’s response is twofold. First, he seems to think that a property dualist must accept the entire Cartesian metaphysics. Second, he says that dualists accept a false dichotomistic vocabulary in which something is either physical or mental but cannot be both.
So biological naturalism is to be distinguished from property dualism in that the former does not include the entire Cartesian apparatus and it rejects this dichotomistic vocabulary.
If this is how Searle distinguishes biological naturalism from property dualism, his response is inadequate. For one thing, it is absurd to claim that one must accept the entire Cartesian metaphysics to be a property dualist. Thomas Aquinas was a certain sort of property (and substance) dualist, but obviously, he did not accept the Cartesian apparatus (cf.
Moreland 1995; Moreland & Wallace 1995). Swinburne defends Cartesian property and substance dualism without accepting Descartes’ entire metaphysical scheme (Swinburne 1986, chap. 8). Moreover, Searle’s own view has a dichotomistic vocabulary in which he distinguishes normal physical (e.g. neurophysiological) properties from emergent biological “physical” (i.e. mental) properties. So he has simply replaced one dualism with another one.
But perhaps there is a different and deeper distinction between (at least) Cartesian property dualism and biological naturalism for Searle. For the property dualist, mental and physical properties are so different that it is inconceivable that one could emerge from the other by natural processes. However, for the biological naturalist, biological physical properties are normal physical properties in this sense: they are like solidity, liquidity, or the properties of digestion or other higher-level properties that can emerge by means of natural processes. I do not wish to comment further on this claim here except to say that Searle’s employment of it to distinguish biological naturalism from property dualism amounts to nothing more than a mere assertion combined with a few undeveloped examples (e.g.
liquidity) that are supposed to be good analogies to emergent mental states. But this assertion is simply question-begging in light of AC and, as I will show later, it amounts to an abandonment of naturalism. At the very least, one should stop and ask why, if Searle’s solution to the mind/body problem is at once obvious and not at all problematic for naturalists, a fi eld of philosophy dominated by naturalists for 50 years has missed this obvious solution?
Searle’s three reasons why biological naturalism is not a threat to naturalism Why are there no deep metaphysical implications that follow from Searle’s biological naturalism? Why is it that biological naturalism does not represent a rejection of scientifi c naturalism which, in turn, opens the door for religious concepts about and arguments from the mental? Searle’s answer to this question is developed in three steps. First, he cites several examples of emergence (e.g. liquidity) that he takes to be unproblematic for a naturalist and argues by analogy that the emergent properties of consciousness are likewise unproblematic.
Step two is a formulation of two reasons why, appearances to the contrary notwithstanding, consciousness is not a problem for naturalists. First, Searle says that naturalists are troubled by the existence of irreducible mental entities because they are misled into thinking that the following is a coherent question that needs an answer: “How do unconscious bits of matter produce consciousness?” (Searle 1994, p. 55; cf. pp. 32, 56–7). Many “fi nd it diffi cult, if not impossible to accept the idea that the real world, the world described by physics and chemistry and biology, contains an ineliminably subjective element. How could
such a thing be? How can we possibly get a coherent world picture if the world contains these mysterious conscious entities?” (Searle 1994, p. 95).
For Searle, the question of how matter produces consciousness is simply a question about how the brain works to produce mental states even though individual neurons in the brain are not conscious. This question is easily answered in terms of specifi c, though largely unknown, neurobiological features of the brain. However, Searle thinks that many are misled into thinking this question is about something deeper and more puzzling.
Setting consciousness aside, in all other cases of entities arranged in a part/whole hierarchy of systems, we can picture or image how emergent features arise because these systems and all their features are objective phenomena. Our problem is that we try to image how consciousness could arise from a system of unconscious bits of matter in the same way, but this is not possible because consciousness itself is not imageable and we cannot get at it through a visual metaphor. Once we give up trying to imagine consciousness, any deep puzzlement about the emergence of consciousness, given naturalism, evaporates, and the only question left is one about how the brain produces mental states.
There is another reason Searle offers as to why the emergence of consciousness has no deep metaphysical signifi cance. In standard cases of reduction, for example, heat and color, an ontological reduction (color is nothing but a wavelength) is based on a causal reduction (color is caused by a wavelength). In these cases, we can distinguish the appearance of heat and color from the reality, place the former in consciousness, leave the latter in the objective world, and go on to defi ne the phenomenon itself in terms of its causes. We can do this because our interests are in the reality and not the appearance. The ontological reduction of heat to its causes leaves the appearance of heat the same. However, when it comes to mental states such as pain, even though an ontological reduction cannot be found, there is a similar causal pattern; for example, pain is caused by such and such brain states.
So why do we regard heat as ontologically reducible but not pain? In the case of heat, we are interested in the physical causes and not the subjective appearances, but with pain it is the subjective appearance itself that interests us. If we wanted to, we could reduce pain to such and such physical processes and go on to talk about pain appearances analogous to the heat case. However, in the case of consciousness, the reality is the appearance. Since the point of reductions is to distinguish and separate reality from appearance in order to focus on underlying causes by defi nitionally identifying the reality with those causes, the point of a reduction for consciousness is missing, since it is the appearance itself that is the reality of interest. Therefore, the irreducibility of consciousness has no deep metaphysical consequences and is simply a result of the pattern of reduction that expresses our pragmatic interests.
In step three, Searle claims that an adequate scientifi c explanation of mental emergence is a set of very detailed, even lawlike correlations between specifi c mental and physical states.
Critique
Searle versus Nagel on causal necessitation
Searle rejects an argument by Thomas Nagel which denies that mere correlations amount to a scientifi c explanation. In terms of AC, Nagel would accept Premise (6) (the explanation is not a natural scientifi c one) and deny that Searle’s correlations count as scientifi c
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explanations. Searle rejects (6) and believes such correlations count as adequate scientifi c explanations. Nagel claims that in other cases of emergence such as liquidity, a scientifi c explanation does not just tell us what happens, it explains why liquidity must emerge when a collection of water molecules gather under certain circumstances. In this case, scientifi c explanation offers physical causal necessity: given certain states of affairs, it is causally necessary that liquidity emerge and it is inconceivable that it not supervene. But, argues Nagel, no such necessity and no answer to a why question is given by a mere correlation between mental states and physical states in the brain.
Searle’s response to Nagel is threefold. First, he says that some explanations in science do not exhibit the type of causal necessity Nagel requires; for example, the inverse square law is an account of gravity that does not show why bodies have to have gravitational attraction. This response is question-begging against Nagel because the inverse square law is merely a description of what happens and not an explanation of why it happens. Interestingly, Newton himself took the inverse square law to be a mere description of how gravity works but explained the nature of gravity itself (due to his views about action at a distance, the nature of spirit, and the mechanical nature of corpuscularian causation by contact) in terms of the activity of the Spirit of God. The point is not that Newton was right, but that he distinguished a description of gravity from an explanation of what it is and his explanation cannot be rebutted by citing the inverse square law. Rather, one needs a better explanatory model of gravity. So Searle’s own example actually works against him.
Moreover, even if we grant that mere covering law explanations are, in fact, explanations in some sense, they are clearly different from explanations that offer a model of why things must take place given the model and its mechanisms. Since the AC assumes the correlations and offers an answer to the why question, Searle’s solution here is not really a rival explanation but merely a claim that such correlations are basic, brute facts that just need to be listed. In light of what we have already seen, there are at least two further diffi culties with Searle’s claim.
First, given AC and the nature of theory adjudication among rivals, it is question-begging and ad hoc for Searle to assert that these correlations are basic, since the correlations themselves, along with the entities and properties they relate are natural and bear a relevant similarity to other entities, properties, and relations in theism (e.g. God as spirit who can create and causally interact with matter), but are unnatural given the naturalist epistemology, Grand Story, and ontology. As we saw in section one, self-refl ective naturalists understand this. Thus, Terence Horgan says that “in any metaphysical framework that deserves labels like ‘materialism’, ‘naturalism’, or `physicalism’, supervenience facts must be explainable rather than being sui generis” (Horgan 1993, pp. 313–4). And D. M. Armstrong’s admits:
I suppose that if the principles involved [in analyzing the single all-embracing spatio-temporal system which is reality] were completely different from the current principles of physics, in particular if they involved appeal to mental entities, such as purposes, we might then count the analysis as a falsifi cation of Naturalism. But the Naturalist need make no more concession than this. (Armstrong 1978b, p. 262)
Horgan and Armstrong say this precisely because mental entities, the supervenience relation, or a causal correlation between mental and physical entities simply are not natural
given a consistent naturalist paradigm. Nor can they be located in Jackson’s sense in the Grand Story. Their reality constitutes a falsifi cation of naturalism for Horgan and Armstrong and, given AC, they provide evidence for theism. It is question-begging and ad hoc simply to adjust naturalism as does Searle, given the presence of AC as a rival explanation.
Naturalists have long criticized Cartesian dualism on the grounds that the causal relation it posits is so bizarre and its relata so disparate that the relation is virtually unintelligible. Many Cartesian dualists are theists and have sought to rebut this claim by appealing to the alleged clarity of divine miraculous activity in the natural world as a counterexample.
However, the dialectical situation worsens if the Cartesian is a naturalist for she must now try to render interaction intelligible solely in light of the resources of the Grand Story, and that cannot be done if the interaction relation is taken to be a natural entity at home in the naturalist ontology. It clearly does not bear a relevant similarity to other entities in that ontology. However, this problem is not a function of the ontological category of the relata.
Specifi cally, it is not a problem that arises for naturalism only if the relata are in the category of individual. It applies equally to the category of property. This is why this problem is sometimes called “Descartes’ Revenge.” Thus, Searle’s employment of a supervenience relation – causal or otherwise – between the brain and consciousness is a serious diffi culty for his biological naturalism, one he does not adequately address.
Second, Swinburne’s version of AC points out that a correlation can be either an accidental generalization or a genuine law (which exhibits at least physical necessity), and we distinguish the two in that laws are (but accidental correlations are not) noncircular correlations that fi t naturally into theories that (1) are ontologically simple, (2) have broad explanatory power, and (3) fi t with background knowledge from other, closely related scientifi c theories about the world. By “fi t,” Swinburne means the degree of naturalness of the correlation and entities correlated in light of both the broader theory of which the correlation is a part and background knowledge. Now Searle admits that mental phenomena are absolutely unique compared to all other entities in that they “have a special feature not possessed by other natural phenomena, namely, subjectivity” (Searle 1994, p. 93) Unfortunately, it is precisely this radical uniqueness that makes mental phenomena unnatural for a naturalist worldview and which prevents Searle from distinguishing an accidental correlation from a genuine law of nature regarding mental and physical correlations.
So much, then, for Searle’s fi rst response to Nagel. His second response is that the apparent necessity of some scientifi c causal explanations may just be a function of our fi nding some explanation so convincing that we cannot conceive of certain phenomena behaving differently. Medievals may have thought modern explanations of the emergence of liquidity mysterious and causally contingent. Similarly, our belief that specifi c mind/brain correlations are causally contingent may simply be due to our ignorance of the brain.
It is hard to see what is supposed to follow from Searle’s point here. Just because one can be mistaken in using conceivability as a test for causal necessity, it does not follow that conceivability is never a good test for it. Only a case-by-case study can, in principle, decide the appropriateness of its employment. Now when it comes to things such as liquidity or solidity, Nagel is right. Precisely because of what we know about matter, we cannot conceive of certain states of affairs obtaining and these properties being absent. That Medievals would not be so convinced is beside the points, since they were ignorant of the relevant atomic theory. If they possessed the correct theory, their intuitions would be as are ours.
But when it comes to the mental and physical, they are such different entities, and the
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mental is so unnatural given the rest of the naturalist ontology that there is no clearly conceivable necessity about their connection. And this judgment is based, not on what we do not know about the two types of states, but on what we do know.
Moreover, a more detailed correlation in the future will not change the situation one bit.
There is no noncircular or non– ad hoc way to formulate such a correlation and we will merely be left with a more detailed dictionary of correlations that will leave intact the same type of problem of causal necessity true of less detailed correlations. Our current lack of belief in such a causal necessity is not due to ignorance of more and more details of the very thing that lacks the necessity in the fi rst place. Rather, it is based on a clear understanding of the nature of the mental and physical, an understanding that Searle himself accepts.
This is why it will not do for naturalists to claim that they are not committed to anything ultimately or utterly brute (such as the divine will), just to their being something unexplained at any given time but which can be explained through deeper investigation. No scientifi c advance in our knowledge of the details of mental/physical correlations will render either the existence of mental entities or their regular correlation with physical ones anything other that utterly brute for the naturalist.
But Searle had another line of defense against Nagel: even if we grant Nagel’s point about the lack of causal necessity in the mental/physical case, nothing follows from this.
Why? Because in the water and liquidity case, we can picture the relation between the two in such a way that causal necessity is easily a part of that picture. But since consciousness is not picturable, we are not able to imagine the same sort of causal necessity. Yet that does not mean it is not there.
Here Searle simply applies his earlier point that, given naturalism, our puzzlement about the emergence of consciousness from unconscious bits of matter is due to our attempt to picture consciousness. Now it seems to me that this point is just false and egregiously so.
I, for one, have no temptation to try to picture consciousness. And other naturalists have put their fi nger on the real diffi culty about the emergence of consciousness. Paul Churchland says:
The important point about the standard evolutionary story is that the human species and all of its features are the wholly physical outcome of a purely physical process. . . . If this is the correct account of our origins, then there seems neither need, nor room, to fi t any nonphysical substances or properties into our theoretical account of ourselves. We are creatures of matter.
And we should learn to live with that fact. (Churchland 1984, p. 21)
Regarding need, I take it he means that everything we need in order to explain the origin and workings of human beings can be supplied by physicalist causal explanations. Regarding room, entities do not come into existence ex nihilo nor do radically different kinds of entities emerge from purely physical components placed in some sort of complex arrangement. What comes from the physical by means of physical processes will also be physical.
Searle is simply wrong about the problem being the imageability of consciousness. The problem here for naturalism is ontological, not epistemological.
Searle versus McGinn on causal necessitation
Searle has one fi nal line of defense against those who place a necessitation requirement on an adequate naturalist explanation for “emergent” properties. Searle seeks to rebut an
argument by Collin McGinn to the effect that such a necessitation requirement is both essential for and unavailable to a strictly naturalist account of consciousness (Searle 1994, pp. 104–5). We will investigate the details of McGinn’s position in section fi ve, but for present purposes, Searle focuses on the following aspects of McGinn’s position: consciousness is a kind of “stuff ” that is known by introspection, things known by introspection are nonspatial, an adequate solution to the mind/body problem requires understanding the
“link” between matter and consciousness, but given our noetic limitations, it is in principle beyond our ability to know that link and, therefore, there is no naturalist account of consciousness. Searle rebuts McGinn on the grounds that (1) consciousness is a property not a stuff; (2) introspection is a confused notion and should be abandoned; given (1) and (2), there is no reason to deny that consciousness is spatial; and moreover (3) there is no link between consciousness and the brain anymore than there is a link between liquidity and H2O.
Setting aside until section fi ve the issue of whether or not Searle has adequately rebutted McGinn’s particular formulation of this argument, the more important point is whether or not Searle has rebutted this form of argument if it is stated in more plausible dualist terms. This is a fair approach to Searle’s rebuttal because he explicitly takes McGinn’s premises to represent broad Cartesian-style commitments (except for McGinn’s claim that the link is in principle unknowable) and his own rebuttal to be successful against Cartesian dualism in general. Given this broader context, I believe Searle’s rebuttal fails. Consider Premise (1). I do not know of a single property dualist (Cartesian or otherwise) who would take mental properties to be a sort of stuff that, for example, should be referred to by mass terms. Even with respect to mental substances, a framework of stuff is not usually employed.
To be sure, some Cartesian dualists may believe in soul stuff, but most substance dualists, including me, employ a substance/attribute ontology to characterize a mental substance as an individuated mental essence; they do not use a separable part/whole framework or the notion of stuff. So Searle is guilty of arguing against a straw man in (1).
What about (2)? Searle’s argument against introspection is as follows:
(1I) If the standard model is true, then there is a distinction (presumably, not a distinction of reason) between the thing seen and the seeing of it.
(2I) The standard model is true.
(3I) Therefore, there is a distinction between the thing seen and the seeing of it.
(4I) If introspection occurs, then there is no distinction between the thing seen and the seeing of it.
(5I) Therefore, introspection does not occur.
There are at least two problems with this argument and they involve (2I) and (4I). Let us begin with (4I). Searle gives no good reason to accept it and, in fact, there are suffi cient reasons to reject it. Let us assume as is standardly granted that in introspection, we have a second-order mental state directed upon a fi rst-order mental state. For example, in introspection the self – whatever it is – is directly aware of a sensation of red or a feeling of pain by directing a second-order mental state onto a fi rst-order one. This is a perfectly intelligible account of introspection and it provides the distinction required to reject (4I).
If someone rejects this model of introspection, then one can still rebut Searle’s argument by rejecting (2I). That is, one can grant (1I) for the sake of argument and deny that it applies to introspection on the grounds that it begs the question. After all, why apply the standard
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model to introspective acts? Recall that in section two I claimed that at least a certain range of mental states relevant to introspection are self-presenting properties. And according to a standard characterization of them, a self-presenting property presents to a subject the intentional object of that property (e.g. an apple’s surface) and the self-presenting property itself (being-an-appearing-of-red). Such properties present other things to a subject intermediately by means of them, and they present themselves to a subject directly simply in virtue of the fact that he has them. Introspective awareness of being-an-appearing-of-red could be understood as the exemplifi cation of a self-presenting property.
In this case, introspection provides a counterexample to the standard model. And while Searle does not mention the self, I see no reason why one cannot be directly aware of oneself. On a certain understanding of intentionality, according to which it is a monadic property, when one is aware of oneself (as opposed to a mental state one has), in direct self-awareness, one simply directs one’s intentionality onto oneself and the subject and object of awareness stand in the identity relation to each other. Nothing Searle says comes close to undermining such an understanding of self-awareness.
Searle similarly attacks a spatial metaphor associated with “privileged access” that he alleges to go proxy for introspection: when I spatially enter something, there is a distinction among me, the act of entering, and the thing entered. No such distinction obtains in alleged acts of “private access” and, thus, “private access” should be rejected. The appropriate rebuttal analogously follows the lines of response given to the argument against introspection.
This brings us to (3). As we shall see further in the discussion, liquidity is a bad analogy with conscious properties. Liquidity may be understood as the property of fl owing freely, which, in turn, may be characterized in terms of friction, fl exibility of bonding angles, degree of spatial compactness, and so forth. In short, liquidity is a structural property and, as such, liquidity constitutively supervenes “upon” a collection of water molecules. There is no causal relation here. Liquidity just is a feature of nonrigid motion constituted by a subvenient base. Thus, it is plausible to deny a “link” between liquidity and a swarm of water molecules. But Searle is clear that conscious properties are simple, sui generis emergent properties and, as such, are causally supervenient on the brain. In this case, there is indeed a causal “link” between the brain and consciousness and Searle’s analogy employed in (3) is a failure, even in terms of his own views.
I conclude, therefore, that Searle has not succeeded in undermining Nagel: Premise (6) of AC (the explanation is not a natural scientifi c one) is correct and Searle’s correlations are not examples of scientifi c explanation which count against (6). But what about Premise (3) (there is an explanation for these correlations)? Why is it not reasonable to take mental entities and their regular correlations with physical entities to be utterly brute natural facts for which there is no explanation? The answer is provided by the arguments just mentioned about why Searle’s correlations are not really scientifi c explanations. Mental entities are not natural or at home in the naturalist epistemology, etiology, and ontology. Given theism and AC as a rival explanatory paradigm, and given the fact that mental entities and correlations are natural for theism, it is question-begging and ad hoc simply to announce that these entities and correlations are natural entities.
Searle could reply that biological naturalism is not question-begging because we already have reason to believe that naturalism is superior to theism prior to our study of the nature of the mental. The only support Searle gives for this claim, apart from a few sociological musings about what it means to be a modern person, is that it is an obvious fact of physics that the world consists entirely of physical particles moving in fi elds of force. It should be
clear, however, that this claim is itself question-begging and clearly false. When there is a statement in a physics text about the world in its entirety, it is important to note that this is not a statement of physics. It is a philosophical assertion that does not express any obvious fact of physics. Moreover, it is a question-begging assertion by naturalists prior to a consideration of the evidence and arguments for theism, including AC. If Searle denies this, then he should inform advocates of AC of exactly what obvious fact of physics they deny in their employment of the argument.
Most naturalists have seen this and have opted for strong physicalism in order to avoid abandoning naturalism and legitimizing the introduction of religious concepts and explanations into the picture. It may be “neurotic” to deny consciousness, as Searle points out.
But it is far from “neurotic” to be driven to do so in terms of a prior commitment to naturalism, and AC makes clear why this is the case.
Mackie on Locke and thinking matter
But perhaps there is a naturalist rejoinder at this point in the form of a tu quoque against theists and AC. J. L. Mackie advanced just such an argument (Mackie 1982, pp. 120–1; Williams 1996; cf. Moreland 1998a, 2000, 2001a). According to Mackie, theists such as John Locke admitted that God could superadd consciousness to systems of matter fi tly disposed and, therefore, as a result of divine intervention, matter may give rise to consciousness after all. Thus, Locke leaves open the possibility that a mere material being might be conscious given theism. Mackie then asks this question: “But if some material structures could be conscious, how can we know a priori that material structures cannot of themselves give rise to consciousness?” (Mackie 1982, p. 121). He concludes that this Lockean admission opens the door for the naturalist to assert the emergence of consciousness from fi tly disposed matter as a brute fact.
In my view, Mackie’s argument carries no force against AC because a main part of AC
consists in the recognition that mental/physical correlations exist, they are not explicable within the constraints of scientifi c naturalism, and they require a personal theistic explanation if they are to be explained at all. In this sense, the idea that, in one way or another, God could “superadd” thinking or other mental states to matter is required for AC to go through.
However, as I have tried to show, it does not follow from this “Lockean admission” that it is a brute, naturalistic fact that material structures of themselves can give rise to consciousness or that adequate naturalistic explanations can be given for this. Indeed, Locke himself constructed detailed arguments to show that mental states such as thinkings are not within the natural powers of matter nor could they arise from material structures without an original mind to create and attach those mental states to matter (Locke 1959, pp. 313–9). Locke’s view that God could superadd thinking to a material substance just as easily as to a spiritual substance was a conclusion he drew from the omnipotence of God along with the claim that “thinking matter” is not a contradiction and, thus, possible for God to bring about.
I am not defending Locke’s way of arguing that God could superadd thinking to matter.
In fact, I do not think it is correct as he formulated it but, clearly, Locke would not have believed that Mackie’s naturalistic conclusion can justifi ably be drawn from his own (Locke’s) admission of the possibility of divine omnipotence adding a faculty of thought to a material structure.
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Mackie cannot simply assert that material structures have the power to give rise to consciousness and also claim to be operating with a naturalistic depiction of matter.
According to David Papineau, matter with emergent mental potentiality is not the sort of matter countenanced by naturalists. This is why when Papineau attempts to characterize the physical in terms of a future ideal physics, he places clear boundaries on the types of changes allowed by naturalism for developments in physical theory. According to Papineau, the naturalist will admit that future physics may change some features of what we believe about matter, but in light of a naturalist commitment and the past few hundred years of development in physics, future physics will not need to be supplemented by psychological or mental categories (Papineau 1993, pp. 29–32).
Given theism, we cannot say a priori just what capacities or states God will correlate with specifi c physical states. But given naturalism, and the commitment to the role of physics in naturalism, along with a view of the physical that is required by physics, we can say that mental potentiality is just not part of matter. Thus, it is question-begging and ad hoc against AC for Mackie to adjust naturalism to allow that material structures of themselves can give rise to consciousness.
Consciousness, liquidity, solidity, and digestion
There is one fi nal issue in Searle’s defense of biological naturalism that needs to be addressed, viz., his claim that the emergence of consciousness fi ts a broad pattern of emergence, for example, cases of liquidity, solidity, digestion, and, therefore, since the latter present no problem for naturalism, neither does the former. I offer three responses. First, if we take liquidity or solidity to be the degree of rigidity, fl exibility, or viscosity of a collection of particles, then these properties are not good analogies to consciousness because they turn out to be nothing more than group behavior of particles placed in a relatively compressed, stable, ordered structure for solids or a more viscous, less compact arrangement for liquids.
So there is no problem about emergence here, since we can easily understand how liquidity and solidity are related to groups of material particles as they are depicted in physical theory.
Second, when we are dealing with genuinely emergent properties that are categorially different from what physical theory takes to characterize subvenient entities, I think that it could be argued that the naturalist has the same diffi culty here as with the emergence of consciousness. Recall Searle’s point about the pragmatics of reduction: we reduce heat to its causes because we happen to be interested in the objective causes and not the subjective appearances, but in cases of, for example, pain, we are interested in the painful appearance itself, so we do not reduce pain to its causes. In my view, the decision to reduce heat to its causes is not primarily a scientifi c matter nor is it a matter of our pragmatic interest. I think it has been a function of two things.
First, if we take heat, color, liquidity, or solidity to be identical to the qualia we experience in certain circumstances (e.g. heat is identical to warmth, red is a color not a wavelength, liquidity is wetness), then an ontological puzzle arises analogous to the one about the emergence of mental states: how could warmth emerge in a physical structure as a result of increased atomic agitation? Second, there was a way of avoiding this question in light of a widely held Lockean view of secondary qualities and sense perception. We can locate these secondary qualities in consciousness and identify them as appearances of the real objective phenomena, viz., the objective causes for our experiences of secondary qualities. John Yolton has shown that
during late seventeenth- and early eighteenth- century debates about materialism, imma-terialist philosophers (e.g. Ralph Cudworth) regularly argued against the idea that mental entities could emerge from properly structured matter (Yolton 1983, pp. 4–13). A standard rebuttal to this claim was that light and heat were very different from matter but could be generated in material bodies given the right conditions. So mind could likewise emerge.
Cudworth and others responded by asserting that light, heat, and other secondary qualities were not in material bodies but were sensations in minds and, thus, the problem does not arise as to how they could arise in a material structure devoid of such qualities prior to the right conditions obtaining. It is clear from this debate at the very beginning of the emergence of modern materialism that one philosophical motive for locating secondary qualities in consciousness was to avoid a straightforward metaphysical problem: ex nihilo nihil fi t.
If I am right about this, then the ontological puzzle is really the driving force behind what Searle calls normal naturalist cases of emergence. The problem is that these cases are not natural any more than the emergence of consciousness and that is why they were located in consciousness. For example, both secondary qualities such as redness or warmth and painfulness are dissimilar to the properties that constitute an ideal physics. Jaegwon Kim has argued that in Nagel-type reductions, the relevant bridge laws should be taken as biconditionals and not as conditionals because we need materially equivalent correlations between entities (or terms) in the reduced and base theories in order to assert identities between the entities in question (Kim 1996, p. 91). Moreover, says Kim, the identity of reduced and base entities is preferable to mere correlations because the latter raise potentially embarrassing questions as to why such precise correlations arise in the fi rst place.
Kim’s point is not confi ned to mental and physical correlations. All a naturalist can do with them (if we keep these so-called secondary qualities or other categorially distinct emergent qualities in the external world) is to offer a detailed correlation to describe regular relations between physical structures and emergent entities. No amount of knowledge whatever of subvenient entities would take us one inch toward predicting or picturing why these particular entities regularly emerge in such and such circumstances and not others.
In discussions of emergence over a century ago, it was precisely their unpredictability from knowledge of subvenient entities that was identifi ed as the hallmark of an emergent property.
In more modern terms, it is the inability to either image or understand why warmth emerges regularly here and not somewhere else, or why it emerges at all given our knowledge of molecular agitation. Note carefully that Searle himself seems to accept picturability as a necessary condition for the acceptance of a claim that one entity emerges from another in the “normal” cases, but picturability is no more available for heat (warmth) emerging from matter than it is for mental states (Searle 1994, pp. 102–3). Nagel’s conceivability test applies here just as it does for mental states.
However, even if I am wrong about this, there is a third response that can be given to Searle. There are two features of mental states that make their emergence disanalogous to, say, the properties of digestion. First, mental states are so unique and different from all other entities in the world that it is far more diffi cult to see how they could emerge from physical states than it is for the so-called normal cases. Second, mental states are quite natural in a theistic world view and have a higher prior probability given theism over against naturalism even if we agree that, say, the emergence of the properties of digestion are equally natural and probable on both world hypotheses.
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In my view, these two features of mental states make them more analogous to value properties than to characteristics of digestion. Mackie argued that the supervenience of moral properties would constitute a refutation of naturalism and evidence for theism:
“Moral properties constitute so odd a cluster of properties and relations that they are most unlikely to have arisen in the ordinary course of events without an all- powerful god to create them” (Mackie 1982, p. 115; cf. Moreland & Nielsen 1993, chap. 8–10). Presumably, Mackie’s reasons for this claim involve some of the points I have just made earlier: moral properties have the two features that make them natural for theism but unnatural for naturalism. No matter how far future physics advances our understanding of matter, it will not make the emergence of moral properties the least bit more likely, more picturable, or more natural. And the same claim could easily be made for mental properties even if features of digestion are granted equally natural for theism and naturalism.
Searle himself admits that of all the entities in the world, mental states are absolutely unique and radically different from all the others. And as we saw earlier, Armstrong is willing to accept that more ordinary physical or biological properties could emerge when the nervous system reaches a certain level of complexity. But he could not accept the natural emergence of mental states from matter because mental states are of “a quite different nature” from states accepted by naturalists. The jump from physical states to mental states was too far for Armstrong’s naturalism to allow, so he adopted strong physicalism as the only acceptable naturalist solution.
The problem with my third response is that it requires one to weigh the difference between acceptable and unacceptable cases of emergence. But to the degree that mental entities are taken as radically unique from all other physical or biological entities, then to that degree the analogy between the emergence of mental states and other cases of emergence is weakened. And to that degree, the emergence of the mental would be radical as Nagel calls it or unnatural as Adams and Swinburne claim.