Unsatisfied with strong physicalism on the one hand and the various extant naturalist solutions for the origin of consciousness on the other hand, Colin McGinn has offered the most radical ‘‘naturalist’’ alternative to date.1 It is so bizarre that it is fair to question whether, even if successful, it is a naturalist position in any meaningful sense of the term. In this chapter, I shall describe and seek to rebut McGinn’s position.
According to McGinn, there is a radical difference between mind and matter. Furthermore, because of our epistemic limitations inherited from evolution, there is in principle no knowable naturalistic solution to the origin of consciousness or its regular correlation with matter that stays within the widely accepted naturalist epistemology and ontology. Nor is there a plausible non-natural alternative. What is needed is a solution radically different in kind from anything previously offered, one that must meet two conditions: (i) It must be a naturalistic solution. (ii) It must depict the emergence of consciousness and its regular correlation with matter as necessary and not contingent facts. More specifically, there must be three kinds of unknowable natural properties that solve the problem. We can unpack McGinn’s position by examining four different aspects of his view.
McGinn and property/event dualism
First, McGinn is committed to property/event dualism. He defines consciousness by giving first-person, introspective, ostensive definitions of particular phenomenal states. He also believes that a fairly simple form of the Knowledge Argument is conclusive. I think McGinn is correct about this, but more importantly, since we are granting premise (1) of AC, I shall simply accept McGinn’s characterization and defense of property/event dualism.
96 Colin McGinn and mysterian “naturalism McGinn on standard naturalist solutions
Second, he rejects all the standard naturalist solutions for many of the reasons mentioned in chapter one: the uniformity of nature; the inadequacy of Darwinian explanations; the centrality for naturalism and inadequacy of combinatorial modes of explanation along with the bottom/up combinatorial processes constitutive of the Grand Story; the acceptance of a necessitation requirement for an adequate naturalist account. Since I have elaborated on these themes already, let us also grant these points to McGinn.
McGinn on anti-naturalist solutions
Third, various anti-naturalist solutions must be rejected. He evaluates and rejects three of them: theistic dualism and AC, hyperdualism and panpsychism. I shall set aside until chapter six a discussion of panpsychism. For now, let us examine McGinn’s treatment of the other two positions beginning with theistic dualism and AC.
McGinn agrees that AC is a plausible argument and, indeed, that there is no plausible rival explanation for a naturalist outside of his own. But for six reasons, AC is a bad argument. For one thing, if we appeal to a conscious God to explain finite consciousness, we generate a vicious infinite regress for we will have to explain why God Himself is conscious. Moreover, if we stop the regress with an unexplainable conscious God, we could just as easily do the same thing by taking finite consciousness as an unexplainable brute fact.
Second, the God hypothesis dignifies consciousness with the word ‘‘soul’’ as an independent thing that uses the body, and thereby generates unanswerable questions that undercut AC: Do rats have souls? Why does God give souls to rats and not worms? Third, theists exaggerate the gap between minds and brains. Mind depends on brain. Why would this be so if mind depends on God?
Fourth, the existence of causally powerful substantial souls that are in some sense dependent upon brains to which they are contingently connected leads to the zombie problem. Such a view renders zombie worlds possible, namely, a world just like the actual one in which minds and consciousness are absent. Now, such a world seems prima facie possible, says McGinn, but on further inspection, it faces an insurmountable difficulty. It means that consciousness is epiphenomenal and any view that entails epiphenomenalism must be rejected. Epiphenomenalism ensues because if a zombie world is possible if follows that the physical will chug along just the same regardless of whether or not consciousness obtains. McGinn’s employment of an (alleged) association of epiphenomenalism and the possibility of zombie worlds to deny the latter is far from idiosyncratic. For example, John Perry claims that zombies are possible if and
only if epiphenomenalism is true; it is a matter of commonsense that epi-phenomenalism is false, so zombie worlds are impossible. Zombies are conceivable only in the sense that it is conceivable that Clemens is not Twain, and this sort of reflexive conceivability is clearly consistent with identity.2
Fifth, we do not know how God produces consciousness, so at best AC is a stalemate vis-a-vis naturalism. Finally, AC gets off the ground only if we grant that consciousness is a mystery for which we need an explanation. However McGinn claims that his account provides a deflationary explanation for why consciousness is a mystery and, in so doing, it becomes obvious that the sort of mystery involved is not of the right kind needed to justify AC.
What about hyperdualism? On this view, there are two realms of rea-lity—the physical world and an undifferentiated, homogeneous sea of conscious entities that are the constituents of consciousness—that causally interact with each other. When brains evolve to an appropriate level of complexity, a hole is punched through to the mental realm and interactions begin to take place. McGinn gives two reasons for rejecting hyperdualism: It violates physical causal closure and its fatal flaw lies in the notion of causality it employs: How could disembodied consciousness cause anything? How could physical sequences in one realm be disrupted by what is happening in a parallel universe? Physical causation in the physical universe involves energy transfer. But can we really use energy transfer for such a bizarre notion of causality, which is entailed by hyperdualism? Once we raise these questions, it becomes obvious that hyperdualism is inadequate and too outlandish to be taken seriously.
McGinn’s solution
Finally, McGinn offers his own ‘‘solution’’ to the problem. He begins by claiming that while evolutionary processes formed noetic faculties in us apt for doing science, it did not develop faculties capable of doing philosophy. Thus, we have cognitive closure regarding philosophical topics, where an organism has cognitive closure with respect to some domain of knowledge just in case that domain is beyond the organism’s faculties to grasp. An area of inquiry in which there is no progress is a good sign of cognitive closure, and philosophy in general, and the mind/body problem in particular, are cognitively closed to human faculties due to their limitations that follow from the evolutionary processes that generated them. Thus, the mystery of consciousness would be no mystery at all if we did not have the cognitive limitations we do.
What we can do, however, is characterize the kinds of conditions that must be true of any solution that would be adequate. According to McGinn, there must be some order underlying the heterogeneous appearances of mind and matter because nature abhors a miracle. Moreover, as I mentioned above, McGinn further claims that (i) It must be a naturalistic solution. (ii) It must depict the emergence of consciousness and its regular correlation with matter as necessary and not contingent facts. More specifically, there must be three kinds of unknowable natural properties that solve the problem. First, there must be some general properties of matter that enter into the production of consciousness when assembled into a brain. Thus, all matter has the potentiality to underlie consciousness. Second, there must be some natural property of the brain he calls C* that unleashes these general properties under the right conditions. Third, just as the brain must have a hidden unknowable structure that allows consciousness to emerge from it, so consciousness must have a hidden unknowable essence that allows it to be embedded in the brain.
There is one final aspect to McGinn’s position that provides a naturalistic solution to the apparent non-spatiality of the mental. According to McGinn, ours is a spatial world yet conscious states have neither spatial extension nor location. This raises a problem: If the brain is spatial but conscious states are not, how could the brain cause consciousness? This seems like a rupture in the natural order. The non-spatiality of consciousness raises serious problems for emergence and causal interaction. McGinn proffers two solutions to this problem. First, he argues that the Big Bang had to have a cause, this cause ‘‘operated’’ in a state of reality temporally prior to the creation of matter and space, and this reality existed in a nonspatial mode. Therefore, the cause of the Big Bang was not spatial or material, yet it obeyed some laws in the prior state. At the Big Bang, we have a transformation from non-spatial to spatial reality, and at the appearance of consciousness, we have a converse transformation. The nonspatial dimension continued to exist in matter after the Big Bang, lurking behind the scene until brains evolved at which time this dimension showed itself again.
McGinn’s second solution focuses on our concept of space. Typically, we think we are correct to depict space as a three-dimensional manifold containing extended objects. But perhaps this depiction is wrong. Maybe its not that consciousness is non-spatial; perhaps it is spatial according to the real nature of space that is quite different from the commonsense view. If we define ‘‘space’’ as ‘‘whatever is out there as a containing medium of all things,’’ then it may be that the real nature of space allows it to contain consciousness and matter in a natural way. Here the Big Bang was a transformation of space itself and not a transition from non-space to space.
I do not believe that McGinn’s position will be widely accepted and that for good reason. In this section I will criticize his evaluation of theistic dualism and AC, surface an inconsistency with his rebuttal of hyperdualism and show how McGinn’s aversion to hyperdualism is relevant to the relationship between naturalism and abstract objects, and rebut his own solution. Let us begin with McGinn’s arguments against theistic dualism and AC. I shall reserve discussion of McGinn’s view of the mystery of consciousness for latter when I examine his positive solution.
Theistic dualism and AC
McGinn argues that by appealing to God to explain finite consciousness, one generates a vicious infinite regress and if the regress is stopped with Divine consciousness as a brute fact, then one could just as easily stop with finite consciousness. This sort of argument has been around a long time and McGinn appears to be ignorant of what many believe is a long-standing, successful rebuttal to it. Let us consider the first horn of McGinn’s dilemma. McGinn seems to think that if we acknowledge there is a problem with cases of finite consciousness that must be solved by appealing to other finite consciousness, then this problem generalizes and applies equally to a conscious God. Unfortunately, McGinn is wrong about this and fails to appreciate what motivates the relevant regress and the sort of regress it is.
For one thing, the infinity of the regress is impossible because it involves traversing an actual infinite and, arguably, that cannot be done. To illustrate, one cannot count from one to @0 for no matter how far one has counted, he will still have an infinite number of items to count. Such a task can begin, but it cannot be completed. Moreover, trying to count from —0א to 0 can neither be completed (it involves the same number of tasks as going from one to @0) nor begun for the following reason: Trying to reach any number in the past will itself require an infinite traversal as a preliminary step. Now in a per se regress (see below), the transitivity of the relation ordering the regress implies that the dependence among members runs from the earlier to latter members. Thus, such regresses are precisely like traversing from @ to 0. Space considerations forbid me to discuss this line of argument further, but in philosophy of religion it is part of what is called the Kalam cosmological argument. I believe the argument is sound, and I refer the reader to some relevant sources that provide a more thorough evaluation of it than can be done here.3
If this is correct, the regress must be finite, and this requires there to be a first member. Below I shall describe some necessary conditions that must be satisfied if one is to select an adequate first member. For now, I merely note that it is not an arbitrary decision to stop the regress because it is vicious, indeed.
The first problem with the existence of an infinite regress of the sort McGinn mentions is, as it were, its length—it involves traversing an actual infinite series of members. Besides, with the problem of traversing an actual infinite, there is another problem with the regress that McGinn fails to note: by its very nature it is vicious. To see this, let us ask how should “vicious’’ be characterized here? At least four characterizations have been offered. Roderick Chisholm says that “One is confronted with a vicious infinite regress when one attempts a task of the following sort: Every step needed to begin the task requires a preliminary step.’’4 For example, if the only way to tie together any two things whatever is to connect them with a rope, then one would have to use two ropes to tie the two things to the initial connecting ropes, and use additional ropes to tie them to these subsequent ropes, and so on. According to Chisholm, this is a vicious infinite regress because the task cannot be accomplished.
D. M. Armstrong claims that when a reductive analysis of something contains a covert appeal to the very thing being analyzed, it generates a vicious infinite regress because the analysis does not solve anything, but merely postpones a solution.5 No advance has been made. He says that this is like a man without funds who writes checks from an empty account to cover his debts, and so on, forever.
Chisholm and Armstrong’s analyses are helpful. But by far, the most sophisticated treatment of regresses, including vicious ones, was provided by Thomas Aquinas and Duns Scotus. According to Thomas Aquinas a vicious regress is a per se regress which exhibits two key features:6 1) It is not just a list of members, but an ordering of members in the sequence. 2) The relationship among the members of the series is transitive. If a stands in R to b and b in R to c, then a stands in R to c, and so on. According to Aquinas, if there is no first member in the series that simply has the relevant feature in itself, no other member of the series will have that feature since each subsequent member can only “pass on’’ that feature if it first receives it.
As an analogy, consider a chain of people borrowing a typewriter. Whether or not the chain is vicious depends on one’s view of the correct description of entities at each stage in the chain. Suppose a goes to b to borrow a typewriter and b complies, claiming to have just what a needs. If asked how b has a typewriter to loan, he claims to have borrowed it from c who, having already borrowed one from d, has one to give to b. Allegedly, at each stage in the chain, the relevant entity can be described as ‘‘a possessor of a typewriter who can loan it to another.’’ Thus, it is alleged, the regress is not vicious.
But it is incomplete to describe each person as ‘‘a possessor of a typewriter who can loan it to another.’’ Rather, each person is ‘‘a possessor of a typewriter who can loan it to another who first had to borrow it from another.’’ At each stage, the person qua lender is such only because he is also a borrower from another, and this means that, given the nature of the series, each stage cannot be adequately described without reference to the earlier stage. Because each member is a borrowing lender, no one will ever get a typewriter unless the regress stops with someone who differs from all the other members of the series in being a lender who just has a typewriter without having to borrow it.
The analogy with finite conscious beings should be apparent. Because they are contingent, then in Chisholm’s terms, before each such being can give what it has (consciousness) to another, it must first undergo the preliminary step of receiving finite conscious being first. In Armstrong’s terms, each member of the chain exhibits the same problematic feature, namely, being a lender of consciousness who must himself ‘‘borrow’’ consciousness from another. In Aquinas’ terms, the members of the regress qua conscious lenders stand in a transitive relationship to the relevant other members in the chain, so without a member who just has consciousness without lending it, there would be no consciousness.
Finally, Duns Scotus offered detailed analyses of various regresses some of which is relevant for present purposes.7 According to Scotus, there are two very different sorts of ordered sequences involving causal or other sorts of dependence relations: An essentially ordered or per se regress and an accidentally ordered or per accidens regress. The former are irreflexive (if reflexive, then Scotus says one will have self-causation which is absurd), asymmetrical (if symmetrical, then a member will be both a cause and an effect of the same member in the series), and, most importantly, transitive. In some essentially ordered regresses, an earlier member actually causes a latter member to cause: either a causes effects in b sufficient for b to cause the relevant effect in c (a effects b) or a causes b’s causing c (a affects b). In various sorts of per se dependency chains, the ordering of dependency is (at least) an ordering of necessary dependency conditions from earlier to latter members in the chain.
Scotus identifies three essentially ordered regresses relevant to our discussion: existence, getting the power to operate, and exercising the power to operate. Scotus’ main argument against the infinity of such regresses is crafted to avoid a fallacy of composition (e.g. since each member of the series is dependent, the whole must be dependent). His argument is that there is something in the final effect, the last member of the chain about which we are puzzling and seeking an adequate explanation (existence, causal power, consciousness), which is missing in all the other members precisely as essentially ordered with respect to each other, and that requires a first member that is (1) not a part of the chain and (2) simply has the feature of the final effect in itself without having to get it elsewhere.
But why must we stop with God and not some particular finite conscious being? This brings us to the other horn of McGinn’s dilemma. The decision to stop with God and not some finite conscious being is not arbitrary but, rather, justified for the following reason. The sort of regress we are considering is one such that in the respect relevant to the ordering of the regress’s members, the stopping place must be unique and different from all others. In the typewriter case, the relevant respect is that each member does not simply have a typewriter; he is himself one who must borrow before he lends. The proper stopping place is with a ‘‘first-mover’’ who simply has a typewriter with no need to borrow one before lending it.
Now, each finite conscious being is contingent in two senses: with respect to its existence and with respect to the fact that consciousness was actualized in it. These types of contingency disqualify finite conscious beings from being the proper first mover. Being a necessary being in both senses, God is such a proper First-Mover.
This kind of dialectic occurs frequently in philosophy. To see this, consider the development of agent-causal theories of human freedom. An advocate of agent causation begins with certain concerns about human action and responsibility, formulates a set of arguments for regarding agent causation as the best view of action and responsibility, and confronts a problem with that view, viz., what does the agent do to bring about an action? Partly in response to this question and out of a desire to avoid a vicious infinite regress, the advocate of agent causation arrives at the view that an agent cause is a first-cause, a first-mover, an entity that may bring about a change without having to change first or be changed to do so. In this sense, agent causes are sui generis compared with ordinary event causes in that the latter are changed changers characterized by passive liabilities; and agents, being characterized by sui generis active power, cannot be caused to act freely.
In epistemology, foundational beliefs are discovered to be such that they provide justification for non-foundational beliefs without having to receive their entire justification from their relationship with other beliefs. In one way or another, foundationalists stop the epistemic regress with an epis-temic first-mover, e.g. a non-doxastic self-presenting property. In ontology, discussions of relations and Bradley’s famous regress lead to the notion that relations are discovered to be able to relate relata without having themselves to stand in a different relation to those relata. They are unre-latable relaters. AC is an argument form relevantly analogous to these.
McGinn’s second critique of theistic dualism and AC is the claim that it uses ‘‘soul’’ to dignify consciousness and this generates serious difficulties (do rats have souls and, if so, why rats and not worms?). As it stands, this is not much of an argument. For one thing, it is simply false. AC does not quantify over souls in any of its premises, and premise (1) launches AC because of the existence of consciousness or its law-like correlations with the brain.
Second, the question ‘‘Why do rats have souls and not worms?’’ is an ambiguous question. If it is the question ‘‘Why would God, if He exists, give souls to rats and not worms?’’ presumably, the answer would be along the lines of why I painted my dining room walls and not the bathroom yellow: I wanted to. What is so problematic about that? If He exists, presumably, God wanted to create certain things and give them certain accidental attributes, and He did not wish to do so for other possible beings He refrained from creating or giving certain accidental attributes. If, instead, the question is about why some things are conscious and others are not, one could say that this is just part of the nature of different things. It is part of the nature of a rat to be conscious and not part of the nature of, say, a tree or rock. Obviously, such an answer involves a commitment to some form of essentialism. But whether or not essentialism is a plausible metaphysical framework is not specifically a theistic concern. This theistic response could employ ‘‘nature’’ in a variety of ways and still be successful.
Finally, focusing on consciousness and not souls, McGinn may be claiming that there is a sort of arbitrariness about theistic dualism such that it entails that at some point, God rather arbitrarily decided to create beings with consciousness and others without it. In response, the sort of ‘‘arbitrariness’’ that seems to underlie this claim is precisely what one would expect if property dualism is true. On a widely accepted dualist understanding of the knowledge of other minds, one starts with first-person acquaintance of one’s own mental states and is justified in attributing to other minds whatever mental states are needed to explain the organism’s behavior. Ontologically, an organism either is or is not conscious; it either does or does not have some specific mental state. However, epistemologically, as organisms become increasingly disanalogous to humans, one is less and less justified in attributing specific mental states or consciousness itself to the organism. Thus, one is increasingly less justified in such attributions applied to another normal human, a dog, a rat, or a worm. As with other cases involving degreed properties (in this case, ‘‘being justified to such and such a degree’’), sorites-style difficulties surface about drawing precise lines among the relevant ordered entities. However, far from being a problem, this is precisely what one would expect from a dualist perspective and McGinn is mistaken if he thinks otherwise.
McGinn also criticizes theistic dualism and AC because, if true, it entails that consciousness depends entirely on God’s will but this is not true since consciousness clearly depends on the brain. Again, McGinn’s objection is ambiguous. I can see two interpretations each of which is fairly easy to rebut. First, his question may be interpreted as assuming that if something depends entirely upon God, then it will not depend on something else in any sense of the word. However, this is a bizarre view of Divine providence and God’s continual act of sustaining contingent beings in existence. No matter what the precise theistic formulation of these matters is, theists agree that there is a relevant distinction between primary and secondary causality. For example, just because God created and continually sustains the physical universe and its laws, and is in this sense that upon which they ‘‘depend entirely,’’ it hardly follows that lightning does not causally depend on certain antecedent conditions within the cosmos. Various causal relations and dependencies within the created order are consistent with the view that if God had not created and does not continually sustain the universe (or some feature within it), then the universe (or some feature within it) would not exist. Clearly, there is no problem here.
Alternatively, the question may be interpreted as asking why, if the creation of consciousness is a contingent act of God, there is a co-varying dependence among life forms according to which as brains become less and less complex, consciousness does so as well. Note carefully the sort of question this is. It is a theological question about why God would arrange things in this way. So understood, the question is not a request for a scientific answer or even a distinctively philosophical one. It is a question whose answer requires reference to God’s possible intentions and motives for arranging things in this way. As I see it, the question is part of a larger one about why there are bodies in the first place.
What are the adequacy requirements for a theological answer to this question? In my view, we have a situation parallel to the difference between a theodicy and defense regarding the problem of evil for theism. A theodicy aims at providing an account of why God actually permits evil in the world. By contrast, a defense offers no such account but seeks merely to show that atheists have failed to carry their case that evil is inconsistent with the existence of God. A defense seeks to undercut the atheist’s argument by providing a possible solution because there is a substantial burden of proof on the atheist for which a defense is adequate.
By way of application, it is hard to see that this problem has much force to it. McGinn would need to give reasons for thinking that the dependency of mind on the brain in the manner specified above (and the dependency goes in both directions) is such that there is no reason God would have for creating such a situation. To be successful, McGinn would have to assume that there is no possible reason for God to make things this way. But it is hard to see why this would be the case. The theist could easily hold that God has reasons for doing things this way and even if the details of those reasons are not available to us, the mere fact that God could easily have them is sufficient to undercut this objection.
Moreover, according to a theology of the body that I favor, God created bodies to provide a source of power for living things so they could act in ways independent of God’s own exercise of efficient causal power. Bodies provide power for action in the created world. Further, the more complicated an animal’s consciousness is, the more complex and finely tuned the body would need to be in order to be responsive to the fine-graded mental states in causal interaction with it. Consider a form of consciousness with a complexity sufficient to engage in a variety of quite specific actions associated with precise nuances in thought, believe, emotion, desire and so forth. On this view, if such a consciousness were causally connected to a material object without the physical complexity needed to register in the physical world the appropriate mental complexity, that mental complexity would be wasted. Such a theology of the body is clearly a possible reason God could have for making things the way he has, and it is sufficient for the purposes of defense required to undercut McGinn’s objection.
McGinn’s fourth criticism of theistic dualism is that, if true, it entails the possibility of zombie worlds that, in turn, entails an implausible epiphe-nomenalism regarding conscious states. But the latter entailment is not the case. One could consistently embrace a form of dualism that entails the possibility of zombie worlds, and also believe that causal interaction between consciousness and matter in the actual world is contingent. From this, it follows that an epiphenomenal world is, indeed, a possible world, but it does not follow that the actual world is an epiphenomenal one. One could go on to unpack ‘‘brings about’’ in ‘‘mental state M brings about brain state B’’ in terms of causal necessitation, viz., ‘‘M brings about B in all interactionist worlds relevantly similar to the actual world.” All this is clearly consistent with the ontological possibility of zombie worlds. The theistic dualism can cheerfully grant that such worlds are distant ones indeed, since her argument goes through quite irrespective of considerations about the remoteness factor.
I am among those dualists who believe that the causal relation (and any other relevant relations, e.g. the emergent supervenient relation construed in non-causal terms) between consciousness and matter is a contingent one. If God wished, he could have created an epiphenomenal world. Inverted qualia worlds, zombie worlds, the metaphysical possibility of body switches or disembodied existence are part of the case for the contingency of the relevant mind/matter relations. Since McGinn’s objection assumes that dualism entails such contingency, I need not defend it in the present dialectic. Rather, I am arguing that if we grant this contingency and the possibility of both zombie and epiphenomenal worlds, it does not follow that our word is an epiphenomenal one. The dualist will hold that as a matter of contingent fact we live in a world of causal interaction and nothing McGinn says threatens this claim.
McGinn’s fifth objection to theistic dualism and AC is the claim that the theistic solution does not solve anything because it does not tell us how God created consciousness. Without providing such a mechanism, the God hypothesis is vacuous and fails to be an advance over a naturalistic explanation, which likewise fails to answer the how, question.
There are two things to be said in response to this argument. First, McGinn's claim simply fails to understand the logic of personal explanation. I will not repeat here our discussion in chapter two of the nature of personal explanation. I make one simple point: A personal explanation can be epistemically successful without referring to a mechanism or other means by which the hypothesized agent brought about the state of affairs in the explanandum. I can explain the existence and precise nature of a certain arrangement of objects on our dinner table by saying that my wife brought it about so we could have an Italian dinner with the Isslers. That explanation is informative (I can tell its Italian food we’re having, that we are having the Isslers over and not the Duncans, that my wife did this and not my daughter, that natural processes are inadequate). In addition, the adequacy of such a personal explanation is quite independent of whether or not I know exactly how my wife did it.
Many sciences essentially involve formulating justificatory criteria for inferring intelligent agent causes to explain certain phenomena and for refraining from inferring such causes. And in these sciences, such an inference is usually both epistemically justified and explanatorily significant completely independently of knowledge as to how the agent brought about the phenomena. In forensic science, SETI, psychology, sociology, and archeology, a scientist can know that an intelligent agent is the best explanation of a sequence involving the first twenty prime numbers in a row, or that something is an intelligently designed artifact used in a culture’s religious sacrifices, without having so much as a clue as to how the sequence or artifact was made.
Furthermore, an appeal to a particular epistemic value, in this case to the requirement that a necessary condition for successful explanation is that a theory explains how a certain phenomenon was produced, is questionbegging against AC and represents a naive understanding of the role various epistemic values play in adjudicating between rival explanations of some phenomenon.
For one thing, two rivals may solve a problem differently depending on the way each theory depicts the phenomenon to be solved. Copernicus solved the motion of the planets by placing the sun in the center of the universe. Ptolemy solved that motion by a complicated set of orbitals with smaller orbitals (epicycles) contained within larger ones. Each solution was quite different in the epistemic value to which it appealed. Copernicans appealed to simplicity and those who sided with Ptolemy claimed that empirical accuracy was on their side. Thus, the epistemic values for assessing one theory may differ substantially from those relevant to its rival.
I am not saying that rivals are incommensurable. I am simply pointing out that it is often more complicated to compare rivals than McGinn’s objection seems to assume. It is possible for two rivals to rank the relative merits of epistemic virtues 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 virtue. Thus, it is question-begging to claim that a criterion P set by one hypothesis should be most important for its rival such that if it fails to satisfy P it is explanatorily inferior.
Finally, sometimes one rival will consider a phenomenon basic and not in need of a solution, empirical or otherwise. It may, therefore, disallow questions about how or why that phenomenon occurs and, thus, can hardly be faulted for not being fruitful in suggesting lines of empirical research for mechanisms whose existence is not postulated by the theory. As Nicholas Rescher has pointed out:
One way in which a body of knowledge S can deal with a question is, of course, by answering it. Yet another, importantly different, way in which S can deal with a question is by disallowing it. S disallows [Q] when there is some presupposition of Q that S does not countenance: given S, we are simply not in a position to raise Q.8
For example, motion was not natural in Aristotle’s picture of the universe and, thus, examples of motion posed problems in need of explanation. But on Newton’s picture of the universe, uniform, linear motion is natural and only changes in motion pose problems in need of solution. Thus, suppose a Newtonian and an Aristotelean are trying to solve the observational problem of how and why a particular body is moving in uniform linear motion. The Aristotelean must tell how or why the body is moving to solve the problem. But the Newtonian can disallow the need for a solution by labeling the phenomenon as a basic given for which no solution in terms of a how question utilizing a more basic mechanism is possible.
By way of application, theistic dualism could easily take God’s action of creating the existence of consciousness and its precise causal correlation with the brain to be a basic action for which there just is no further ‘‘how’’ question to be asked. Moreover, the theistic dualist can also claim that, given the nature of personal explanation, the epistemic value of citing a mechanism in answer to a ‘‘how’’ question is not as important as other epistemic values and, thus, failure to answer such a question is not a particularly significant issue in light of its own inner logic. But the same cannot be said for naturalism, and given the way physical explanation works, the importance of answering ‘‘how’’ questions by citing a mechanism is, indeed, quite high. Thus, the naturalist’s failure to answer this question is a serious one but the same cannot be said for theistic dualism.
Hyperdualism
So much for McGinn’s criticism of theistic dualism and AC. What about his response to hyperdualism? You may recall that according to McGinn the central reason why hyperdualism must be rejected lies in the notion of causality it employs: How could disembodied consciousness cause anything? How could physical sequences in one realm be disrupted by what is happening in a parallel universe? Physical causation in the physical universe involves energy transfer. But can we really use energy transfer for such a bizarre notion of causality entailed by hyperdualism? These questions make it obvious that hyperdualism is inadequate and too outlandish to be taken seriously.
Since I do not have a dog in this fight, I have no interest in defending hyperdualism. However, I do think that McGinn’s argument against it backfires in such a way that it reintroduces a range of defeaters for naturalism that we are not considering in this book.
To see this, it is important to note that McGinn claims that as long as the naturalist gives an account of the instantiation of all properties in terms of the instantiation of physical properties taken as straightforward physical facts(s), he is free to take properties themselves as non-physical, abstract entities.9 Presumably, on either a constituent or relational ontology, this would mean that the nexus of exemplification is at the very least a queer entity and, most likely, an abstract object in its own right. In fact, the admission of abstract objects—e.g. properties and relations, including exemplifi-cation—and their instantiation is sufficient for naturalist philosophers who are sensitive to matters in general ontology such as D. M. Armstrong, Keith Campbell and Wilfred Sellars to justify a rejection of naturalism.10 For example, Wilfrid Sellars claimed that ‘‘a naturalist ontology must be a nominalist ontology.’’11 Elsewhere, Sellars argued that a nominalist analysis of predication is the ‘‘very foundation of a naturalist ontology.’’12 I have defended these claims elsewhere, and shall not develop them here.13 However, here is a summary of two key issues:
(1) Traditional properties and spatio-temporal location: Some have offered a sort of ‘‘argument from queerness’’ against traditional realist properties construed as abstract objects to the effect that they are entities of a very strange sort, utterly different from anything else in the universe as depicted by the strong naturalist. Some have developed this argument by focusing on a special class of universals (e.g. propositions, axiological properties), others have claimed that no physicalist or naturalist non-reductive account of deep, metaphysical modality is possible and, thus, realist properties and their relations to each other are utterly different from the rest of the naturalist ontology.
(2) Traditional properties and predication: Traditional realism is a classic example of a ‘‘two world’’ ontology and, as such, it becomes difficult to explain in naturalist terms how there could be any kind of connection between abstract objects on the one hand and the spatio-temporal world of particulars and events on the other. Moreover, because the predication relation (i.e. nexus) 1) is non-spatio-temporal; 2) connects entities from different ‘‘worlds’ (How could physical sequences in one realm be disrupted by what is happening in the abstract realm?) and 3) does not involve energy transfer, it is hard to see how the relation itself bears a relevant similarity to strictly physical entities. In this regard, the predication relation presents the same sorts of problems to global naturalists that Cartesian interaction and emergent/supervenient relations do to weak naturalists (e.g. Where does Cartesian interaction take place and where is the predication relation exemplified?).
Naturalists who are persuaded by McGinn’s critique of hyperdualism, must face the fact that this very sort of argument has been forcefully employed by major naturalist figures to justify a rejection of abstract objects. At the very least, McGinn owes us an explanation as to how he can advance his argument against hyperdualism while accepting the conjunction of naturalism and the exemplification of abstract objects. At the end of the day, there may be a much closer relationship between naturalism and rejection of abstract objects than many realize, and McGinn’s argument provides a nice place to raise this problem.
Colin McGinn and mysterian “naturalism” 109 Four problems with mysterian “naturalism”
We come to an evaluation of McGinn’s own position—mysterian ‘‘naturalism.’’ For at least four reasons, it must be judged a failure. First, given McGinn’s agnosticism about the properties that link mind and matter, how can he confidently assert some of their features? How does he know they are non-sensory, pre-spatial or spatial in an unknowable way? How can he confidently assert that we are naturally constituted from smoothly meshing materials, as seamless as anything else in nature? How does he know some of these properties underlie all matter? Indeed, what possible justification can he give for their reality?
The only one he proffers is that we must provide a naturalistic solution and all ordinary naturalistic ones either deny consciousness or fail to solve the problem. However, given the presence of AC, McGinn’s claims are simply question-begging and ad hoc according to criteria developed in chapter two. Indeed, his agnosticism seems to be a convenient way of hiding behind naturalism and avoiding a theistic explanation. Given that theism enjoys a positive degree of justification prior to the problem of consciousness, he should avail himself of the explanatory resources of theism.
In a related fashion, it is sometimes argued, and not without some justification, that attempts to draw a line between what we can and cannot know requires that one must first cross the line to draw it. McGinn comes perilously close to doing the very thing he claims cannot be done. Whether or not one accepts this claim about drawing lines, it seems that McGinn’s view is self-refuting. He tells us that we did not evolve with faculties apt for doing philosophy, that when confronted with a lack of progress we should draw the conclusion that we are cognitively closed to the subject matter in question, and so on. Yet McGinn’s entire book is a species of philosophical argument and he explicitly states that his purpose is to develop and defend his viewpoint over against rivals. He also derives philosophical theses (e.g. skeptical theses in areas for which we have cognitive closure) by philosophically studying the history of philosophy, he gives an analysis of the nature of human knowledge, he offers philosophical—not scientific—arguments against positions that rival naturalism. I may be missing something here, but it is hard to avoid the conclusion that McGinn’s own project is refuted, or at least undercut by his own views that constitute the core of that very project.
Second, it is not clear that his solution is a version of naturalism, except in name only. In contrast to other entities in the naturalist ontology, McGinn’s three hypothesized properties cannot be known by employment of the naturalist epistemology, nor are they relevantly similar to the rest of the naturalist ontology. For the sake of argument, I grant that McGinn may appropriately call these ‘‘naturalistic’’ properties in the sense that they are 1) not created by God and 2) are regularly involved in giving rise to
consciousness in organisms. However, it is vacuous to call these properties ‘‘naturalistic’’ in the only sense relevant to theistic dualism and AC, namely, as entities whose nature, existence and activity can be located in a natural ontology and given a naturalistic explanation. Given that naturalism is a worldview that claims superior explanatory power to its rivals, these are bizarre, sui generis brute facts on a naturalist view. Indeed, McGinn’s ontology is so bizarre that it may be taken as a reductio against naturalism if McGinn is correct that no other naturalist solution is available. In fact, McGinn’s solution is actually closer to an agnostic form of panpsychism than to naturalism. In the next chapter, we shall evaluate panpsychism and discuss whether it can be taken as a version of naturalism. For now, I note that McGinn is clear on the matter: panpsychism is a rival to and not a legitimate specification of naturalism.
Third, McGinn does not solve the problem of consciousness; he merely relocates it. Rather than having two radically different entities, he offers us three unknowable properties with radically different aspects, e.g. his links contain the potentiality for ordinary spatiality and non-spatiality, for ordinary materiality and mentality. Moreover, these radically different aspects of the linking properties are just as contingently related as they seem to be without a linking intermediary. The contingency comes from the nature of mind and matter as naturalists conceive it. It does not remove the contingency to relocate it as two aspects of unknowable intermediaries with both.
Finally, there are serious difficulties with McGinn’s solution to the problem of the non-spatiality of mental states. According to his first option the Big Bang had to have a cause, this cause ‘‘operated’’ in a state of reality temporally prior to the creation of matter and space, this reality existed in a non-spatial mode, and while the cause of the Big Bang was neither spatial nor material, it still obeyed some laws in the prior state.
There is much in this solution that brings a smile to the theist: the Big Bang had to have a cause, presumably because either events per se or those in which something comes-to-be must have causes, the cause is not spatial nor is it material. This cause shares important features with the God of classic theism. At the very least, it is hard to see how the hypothesized state of affairs satisfies the conditions for location in a naturalist ontology specified in chapter one. The presence of temporality is not sufficient to claim this is a naturalistic state of affairs because based on strong conceivability there are possible worlds in which angels alone exist temporally. As Kant argued, finite consciousness entails temporality, so such worlds are temporal but hardly apt for appropriation by a naturalist.
Nor is the presence of law sufficient. In his discussion of constituent/ whole relations, Edmund Husserl described a host of (a priori) laws of being that he claimed governed the nature of various entities, their coming-to-be and perishing, and different changes that take place among them.14 However, these laws are not in any sense physical laws of nature. Even if
Husserl is wrong, his ontology and many others like it demonstrate that the mere presence of laws that govern change in some purported ontological model is far from sufficient to claim that the model is a naturalistic one. Moreover, it seems reasonable to hold that the nature of a relation is constituted by the nature of its relata—spatial, musical, odor, logical relations are such because they can relate certain kinds of entities and not others. If this is right, it is hard to see how the laws envisaged by McGinn are natural laws.
Finally, McGinn seems unfamiliar with the Kalam cosmological argument and the literature surrounding it, a literature of central importance for evaluating his proposal. The argument has generated a lot of attention in the last fifteen years or so and it has no small number of defenders. It is safe to say that the argument is sufficiently robust to require inclusion in any discussion of the beginning of the spatio-temporal physical universe. The Kalam cosmological argument involves a defense of these three propositions:
(1) The universe had a beginning.
(2) The beginning of the universe was caused.
(3) The cause of the beginning of the universe was personal.
Two different philosophical arguments are typically offered on behalf of (1). Argument A
(A1) An actual infinite number of things cannot exist.
(A2) A beginningless temporal series of events is an actual infinite number of things.
(A3) Therefore, a beginningless temporal series of events cannot exist. (A4) Either the present moment was preceded by a beginningless temporal series of prior events or there was a first event.
(A5) Therefore, there was a first event.
Argument B
(B1) It is impossible to traverse an actual infinite by successive addition. (B2) The temporal series of past events has been formed by successive addition.
(B3) Therefore, the temporal series of past events cannot be actually infinite. (B4) Either the temporal series of past events is actually infinite or finite. (B5) Therefore, the temporal series of past events is finite.
(B6) If the temporal series of past events is finite, there was a first event. (B7) Therefore, there was a first event.
It is not my purpose to defend the argument here, but it should be pointed out that, if successful, it justifies the claim that time itself had a beginning that was caused by something that can exist without time. And on the assumption that laws of nature govern temporal processes and, thus, require events to be instantiated, it becomes clear that a law of nature did not govern the cause of the first event. At the very least, McGinn’s speculations regarding his first option are grossly incomplete and they open the door for considerations quite favorable to theism.
What about McGinn’s second option: We are wrong to think of space as a three-dimensional manifold containing extended objects. Perhaps the real nature of space is ‘‘whatever is out there as a containing medium of all things.’’ If this is correct, then the real nature of space allows it to contain consciousness and matter in a natural way.
I do not have a knock-down argument against this option, but I do find it highly counter-intuitive and, in fact, unintelligible. It may be useful to say why. I begin with an observation about the difference between formal concepts and certain material concepts. I recognize that my remarks to follow are controversial and inadequately developed. Still, I want to get some ideas on the table that I take to be relevant to McGinn’s second option, even if they are expressed in precis form.
In my view, formal concepts are capable of being expressed adequately by way of definite descriptions. To illustrate, the formal concept of a substance is “whatever is an essentially characterized continuant;’’ the formal concept of justice is ‘‘whatever outcome is fair and accords with the maxim ‘treat equals equally and unequals unequally’.’’ Functional concepts are good examples of formal concepts. By contrast, material concepts, at least those defined by ostensive definition, are defined by rigid designation. If we limit ourselves to sense perceptible entities with which we may be acquainted, then ‘‘red,’’ ‘‘sour,’’ ‘‘middle C’’ may be taken as expressing material concepts.
Now I take the notion of extension to be such a material concept. If I am right, then the only intelligible notion of a spatial dimension is the material concept of ‘‘extended one-directional magnitude’’ which must be defined ostensively. Along similar lines, ‘‘space’’ is a material concept defined by acquaintance as ‘‘extended three-directional magnitude.’’ I, for one, have no idea what it means to use spatial language to speak of multi-dimensionality in the way McGinn does. When a scientist claims that a threedimensional object can be ‘‘spatially rotated’’ into other spatial dimensions, I can give no material content to the claim and, thus, I cannot understand what is being said. Likewise, when McGinn tell us that space is ‘‘whatever is out there as a containing medium of all things,’ the terms ‘‘out there,” ‘‘containing,'' ‘‘medium,'' are either used in the ordinary way characterized above, in which case the definition is circular and seems to require osten-sive definition to give these terms intelligible content, or else they are used equivocally in which case they are unintelligible, at least to me.
I recognize that physicists talk about a multitude of spatial dimensions. In my view, the scientific notion of an extra dimension of space is a mere mathematical devise, a formal definition with no material content that can intelligibly be ascribed to reality, and theories that employ such language should be understood in anti-realist terms. When scientists speak of multidimensionality with respect to space, they say things like the following: there are millions of dimensions of space, there could be an infinitely small volume, mass and space are literally interchangeable, triangles can be identical to circles, that a one dimensional line (a string) could literally have clockwise vibrations in ten dimensions of space and counterclockwise vibrations in twenty-six space dimensions.15 I find such language unintelligible, and while the problem may be my lack of imagination, I suspect that others may agree with me.
In any case, I have tried to show that McGinn’s position is not as plausible as AC and is not a legitimate version of naturalism. Long ago, Thomas Kuhn taught us that there are certain telltale signs of a paradigm in crisis among which are the proliferation of epicycles, of rival specifications of the paradigm formulated to preserve that paradigm in the face of stubborn, recalcitrant facts. Especially significant are specifications so bizarre that it is hard to recognize them as specifications of the paradigm. I take McGinn’s mysterian ‘‘naturalism’’ to be an indication that naturalism is in serious crisis with respect to consciousness. Kuhn also taught us that as bizarre and ad hoc as some of the specifications may be, if there is no rival paradigm, then an advocate of the degenerative paradigm must simply do the best he or she can with the recalcitrant facts and leave it at that. But if there is a plausible rival, a paradigm shift may well be in order. In my view, McGinn’s position, coupled with theism and AC as a rival, serve as evidence that such a paradigm shift away from naturalism towards theism is past due.