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Philosophy of Mind and Graduate Philosophy Study
Assuming my audience is the same audience I have set out to entertain (graduate students in philosophy), I doubt I am the first one around here who’s applied to multiple PhD programs only to find that none of the good ones saw fit to send them a golden ticket in the mail. Assuming I’m not alone in this, I doubt I am alone in wanting to share my writing sample with the masses. I, like so many before me, spent quite a bit of time writing and editing my writing sample, and it seems like such a waste for it to sit on my hard drive gathering dust while I wait to apply again next year with a different writing sample. Now, seeing as how I have this here “blog” about philosophy of mind, I have an excuse to share my sample which—surprise, surprise—has to do with philosophy of mind.
This paper was originally written over a year ago for a survey course I took in the 20th century analytic tradition, and has since been beaten into submission through multiple re-writes and edits. I’d like to believe the rough edges are all nice and polished, but I doubt that is the case. Regardless, it might be of some interest to those reading this blog. The paper is a relatively basic response to David Chalmer’s “Facing Up to the Problem of Consciousness”. It is not an entirely friendly paper either; I vehemently disagree with Chalmers on mind and I think it shows. I just hope my vehemence does not deter the reader.
Before I get to the paper, I should note that if others would be so kind as to submit a paper of theirs (past writing sample or otherwise) I’d be more than happy to read them and post them with permission. For this particular project the papers need not be directly or even tangentially related to philosophy of mind. I’m more interested in providing fellow graduate students (or those wishing to become graduate students) an avenue by which they can see what others in their position are writing. As graduate students or undergraduates in their final semesters, we don’t often have the chance to publish papers at the academic level, and so we miss out on a great deal of feedback and exposure to other ideas. I hope this sort of practice will help rectify that. Furthermore, these sorts of papers can be a great deal of fun to read, and highly enlightening for those of us without many classmates writing on our same interests. Submissions can be sent to ersatzrobots(at)gmail(dot)com.
With that said, on to the paper…
David Chalmers and the Mystery of the Kool-Aid
By: Galen Mitchell
David Chalmers’ “Facing Up to the Problem of Consciousness” is everything one might expect from the self-styled naturalistic dualist. According to Chalmers, the motivation behind “Facing Up…” is found in the fact that, “[t]here is nothing that we know more intimately than conscious experience, but there is nothing that is harder to explain” (Chalmers, 1). It is this difficulty that moves Chalmers to explicate our problems explaining consciousness in the hope that we might more fully understand them, and perhaps avoid them in our future theories. Chalmers’ analysis results in the identification of what he believes to be one “hard” problem, which is to be distinguished from a variety of “easy” problems. In framing the difficulty of explaining subjective experience in this manner, Chalmers aims to explain why finding an explanation for consciousness is so difficult, and to propose a non-reductive explanation that might show how “…a naturalistic account of consciousness can be given” (Chalmers, 1). My goal, on the other hand, is to explicate Chalmers’ problems explaining consciousness in the hope that we can more easily see why a non-reductive account—naturalistic or otherwise—of consciousness is unnecessary and unproductive. My hope is that by distilling Chalmers’ argument, we will see where there might be impurities, and go about removing them. Following this, I will leverage the insights of U.T. Place, Daniel Dennett, and Paul Churchland to present a methodology by which we might arrive at a more useful account of consciousness.
Before diving into the debate, a bit of setup might be helpful. To start, Chalmers argues that consciousness refers to multiple phenomena, and so treating it as a singular phenomenon is a mistake. Chalmers believes that these different phenomena associated with consciousness pose different degrees of difficulty in explanation—some of them may have a readily available explanation, while others may require more work. Specifically, Chalmers argues that “[t]he easy problems of consciousness are those that seem directly susceptible to the standard methods of cognitive science… The hard problems are those that seem to resist those methods” (Chalmers, 2).
According to Chalmers, the easy problems of consciousness are easy because they can rely on the concepts of functions, simple processing, and other computational analogues for their explanations; their nature makes these sorts of problems resolvable. However, Chalmers contends that these concepts are unable to explain the subjective aspect of consciousness that is found in experience. “When we see, for example, we experience visual sensations: the felt quality of redness, the experience of dark and light, the quality of depth in a visual field” (Chalmers, 3). Chalmers argues that simple information processing cannot account for this sort of experience of “red” because it is qualitatively different from simple processing, or the performing of a function. We like to say that these experiences arise from the physical, but Chalmers agues, “we have no good explanation of why and how it so arises” (Chalmers, 3).
For Chalmers, this requires us to admit that when we talk about consciousness, we seem unable to explain its most compelling component: subjective experience. Admittedly, this often seems to have been the case. However, Chalmers argues that explaining subjective experience is made difficult by the fact that the explanations we use to explain the easy problems—the problems of cognitive functioning—cannot be used to explain subjective experience. When we ask what the performance of a particular function is, we explain the mechanism that performs the function; however for Chalmers, “[w]hen it comes to conscious experience, this sort of explanation fails. What makes the hard problem hard and almost unique is that it goes beyond problems about the performance of functions” (Chalmers, 5). Simply put, experience for Chalmers is qualitatively different than functional processing. The reasons for this claim will become more apparent as we go through the latter parts of Chalmers’ argument. However, it is safe to say that this is the primary issue at hand.
With this supposed qualitative difference in mind, Chalmers rephrases the hard problem of consciousness: the problem is not simply that we experience things, but rather that the performance of cognitive functions is accompanied by experience (Chalmers, 5). For instance, he asks, why doesn’t the brain process information in such a manner that there is no subjective experience of it? Harkening back to Nagel, why is it that there is something it is “like” to be a bat, or any other conscious thing for that matter? More explicitly, “[w]hy is it that when electromagnetic waveforms impinge on a retina and are discriminated and categorized by a visual system, this discrimination and categorization is experienced as a sensation of vivid red” (Chalmers, 6)? According to Chalmers, our current inability to explain this phenomenon—this accompanying phenomenological aspect—leaves us with an explanatory gap. Now, one might easily take issue with this idea of an explanatory gap—especially because it seems to result from Chalmers begging the question by defining subjective experience as fundamentally different from the performance of functions etc. However, saying that would make this critique rather short and uninteresting. So, let us set aside for a moment the issue of whether Chalmers is begging the question and focus on the rest of his argument, which at this point can be summarized as: if we want to understand consciousness, we have to build a conceptual bridge that will take us from cognitive functioning, which seems easy enough to explain via reductive methods, to subjective experience, which Chalmers thinks does not yield to reduction.
In pursuit of a demonstration of how it is that reductive accounts have failed to explain consciousness, Chalmers notes that multiple individuals have attempted to address the problems of consciousness in some manner—it is not a new line of inquiry. However, in line with his anti-reductionist stance, Chalmers believes that when we investigate what these previous inquiries have yielded, we never find an explanation for the hard problem of consciousness. According to Chalmers: “we find that the ultimate target of explanation is always one of the easy problems” (Chalmers, 6). In other words, Chalmers argues that none of these investigations address subjective experience. The second study of this sort that Chalmers addresses shows what he means by this.
This second study in question is Bernard Baars’ global workspace theory of consciousness. Baars’ global workspace theory explains the mind by breaking it down into multiple specialized “processors.” These processors perform the cognitive functions Chalmers previously labeled in relation to the easy problems of consciousness. However, the theory diverges from others by positing a central processor that mediates between different specialized processors that output their information into a “global workspace,” which in doing so render their information available to the central processor (Chalmers, 8). For Baars, this central processor could be said to “experience” in some sense what the other non-conscious processors are simply “making available.” However, while this may get us somewhat closer to a functional model of how experience might be possible, Chalmers contends that “[t]he best [Baars’] theory can do is to say that the information is experienced because it is globally accessible” (Chalmers, 8). In other words, it explains how a thing becomes capable of being experienced, but not why it is experienced. According to Chalmers, there is as yet no necessity for subjective experience to accompany this process.
For Chalmers, this apparent failure of Baars’ theory is not unique. Chalmers believes that all of these sorts of studies either explain something other than experience, or their explanations of experience are essentially non-sequiturs. When we finally realize this, Chalmers believes, we are left with a few different options: we can continue to explain something other than experience; we can deny that subjective experience exists (which Chalmers believes simply ducks the question); we can claim that experience has in fact been explained; we can attempt to explain the structure of experience; or we can explain what experience itself is based on (Chalmers, 9-10). However, Chalmers believes that all of these attempts avoid the hard problem of consciousness, and fail to adequately account for consciousness for different reasons. These “avoidance measures” do have one reason they fail in common: for Chalmers, the hard problem of consciousness requires an “extra ingredient” for any suitable explanation (Chalmers, 10). In other words, Chalmers believes that there is something missing from purely functional, physicalistic process explanations of consciousness, such that they will never be able to account for experience in a meaningful way.
The good news, in Chalmers’ opinion, is that there are plenty of extra ingredients that we might pull into our explanations of consciousness that might provide us with an account of experience. One of our options is “an injection of… nonlinear dynamics” (Chalmers, 10). However, according to Chalmers, this particular concept does not seem to be adequate to solving our problem, because, he argues, from the introduction of dynamics all we can get is more dynamics. If this is the case, experience has remained unexplained, because experience for Chalmers is something qualitatively different than dynamics. It would be nice at this point to have a definition of ‘dynamics’ and a definition of ‘experience’ such that this “qualitative difference” was explained. However, Chalmers has none—for now, we will have to continue to take him at his word.
Continuing the argument, Chalmers asserts that from everything we have found so far, “[t]he emergence of experience goes beyond what can be derived from physical theory” (Chalmers, 12). Chalmers does not think that this failure applies only to explanations that attempt to get at the problem of experience via physical structures and functions; he thinks that it is a condition of any reductive account of the problem, and so applies to all reductive explanations of consciousness. Despite this, Chalmers does not believe that the problem is such that it cannot be solved. Instead, “[w]hen simple methods of explanation are ruled out, we need to investigate the alternatives. Given that reductive explanation fails, non-reductive explanation is the natural choice” (Chalmers, 13). Towards this end, Chalmers provides us with what he believes to be a non-reductive account of consciousness that might provide an explanation for subjective experience. However, now that everyone is up to speed, we should spend a few moments discussing the various claims Chalmers has made so far.
Let us be charitable and just assume for a moment that physicalistic functional accounts cannot, by their nature, account for experience. In this case, Chalmers decides that we must add some additional ingredient to our theory of consciousness in order to gain the ability to explain experience. Here Chalmers suggests that nonlinear dynamics is one ingredient that we might add, but that such an addition fails, because all a system of dynamics can give us is the explanation of more dynamics, and dynamics are not sufficient to explain experience. Without definitions, this simply appears to be more evidence that Chalmers is begging the question. However, there are problems with this statement beyond its lack of specificity and potential question-begging.
First, we ought to take issue with the idea that nonlinear dynamics is a concept we must “import” into a physical/functional account, rather than its being a concept that is necessarily a part of such an account. Calling non-linear dynamics an ‘import’ seems to serve only to legitimize Chalmers’ belief that we must import some other concept into our explanation in order to get an account of consciousness. We might also wonder how it is that explanations of dynamics can only produce more explanations of dynamics. In fact, it seems that dynamical explanations themselves do not “produce” anything, they simply explain the relationships between different dynamical physical systems; perhaps this is what Chalmers means, and perhaps this is why he finds them insufficient. However, this “problem” has been a non-problem since U.T. Place’s “Is Consciousness a Brain Process?”—this “difficulty” is just the result of Chalmers’ endorsing the phenomenological fallacy (Place, 29-30). In fact, what we need is precisely a theory of consciousness that provides us with an explanation of experience’s relationship to the dynamics of functional processes in the brain which, as it so happens, appear to be non-linear. So, in pursuit of this sort of explanation, what better place to start than with a discussion of non-linear dynamics?
However, for the sake of argument, let us assume for the moment that Chalmers is right, and that the current methods of employing non-linear dynamics and physicalistic functional accounts of the brain are insufficient to explain experience. Even here, we are left with a difficulty in Chalmers’ argument: the supposed necessity of a non-reductive account of consciousness. Even if we agree that all physicalistic functional methods employed so far have failed, and that they are all reductive, claiming that all future reductive attempts will necessarily fail is simply an argument ad ignorantum.
Moreover, moving to a non-reductive account in the manner Chalmers does here is even more problematic for those of us who, like Quine, are at home in desert landscapes. There is nothing logically binding in Chalmers’ argument that would force a reductionist to embrace a non-reductive account of consciousness. Chalmers’ own decision to do so is pragmatic—in a highly speculative sense—at best. It seems that Chalmers himself might be ducking the truly hard question by making this move. But perhaps this appraisal is too harsh; Chalmers does believe that there is a logical necessity to this move, and this connection is demonstrated in his previous work on philosophical zombies. We should make this connection more clear.
Rather than taking only physical entities to be fundamental, as reductive accounts do, Chalmers suggests that perhaps experience itself is fundamental. He does this based on his previous works, where he determined that “…a theory of consciousness requires the addition of something fundamental to our ontology, as everything in physical theory is compatible with the absence of consciousness” (Chalmers, 14). This is where we find his argument for the possible existence of zombies—not brain-eating, mall-dwelling zombies, but philosophical zombies. These zombies are, upon observation, completely identical to “normal” conscious humans. However, Chalmers claims, they differ in one regard: they are not in fact conscious. According to Chalmers, any response we might receive from this sort of entity would appear to be a normal response for a conscious being, but the nature of their responses would be mechanistic and without accompanying subjective experiences. The fact that we can conceive of this sort of zombie entails for Chalmers that consciousness must not be purely physical, and that we require some additional component to explain consciousness.
Chalmers’ zombies are troublesome in their own right, regardless of whether they can be used to show the supposed logical necessity of a non-reductive, “naturalistic,” dualist theory of consciousness. The assumption that these zombies are conceivable, seems to point back to the issue I keep coming back to but have decided to avoid for the moment: whether Chalmers is begging the question by defining subjective experience as fundamentally different from the performance of functions etc.
This is because trying to conceive of a “person” without consciousness is harder than Chalmers seems to think. Conceiving of a person without consciousness is like trying to imagine your friend Arthur without his being Arthur. You can try to imagine that someone has zapped him with an anti-consciousness ray, that Arthur is gone and all that’s left is an Arthur-Zombie. However, there he is talking to you, harassing you from behind a wry smile, kissing his wife etc., all like only Arthur can. If you can take away what it is that makes Arthur a person and nothing changes in your estimation of Arthur’s personhood (and by Chalmers’ definition, nothing can change), you must not have taken anything away—unless of course you have already defined physical processes as separate and distinct from consciousness. Chalmers’ zombies are only conceivable if you have already defined people as somehow not being the people of empirical experience, and doing that seems dangerously close, if not identical to, embracing a supernatural form of dualism in which you could never meet the real Arthur, because the real Arthur is above and beyond the empirical, natural Arthur. To be fair, Chalmers claims to be offering a naturalistic account of experience, so perhaps we should hear him out—maybe my zeal has gotten the better of me.
Chalmers’ “naturalistic” account hinges on what he believes to be the additional component, necessary for something to be conscious above and beyond its physical/functional composition. This additional component is experience, and according to Chalmers, “[i]f we take experience as fundamental, then we can go about the business of constructing a theory of experience” (Chalmers, 14). Chalmers defends this move by stating that “[c]ertain features of the world need to be taken as fundamental by any scientific theory” (Chalmers, 15). On the face of it, this does not seem to be that strange. After all, a physicalist takes physicality to be fundamental in order to explain the world, and Chalmers simply believes we must add experience onto that if we are going to explain consciousness.
However, there is one essential difference between these assumptions: assuming physicality has proven to have massive explanatory power and has shown itself to be invaluable to us in our practical lives. The assumption of physicality has directed all of modern science and is logically necessary to the continuation of our doing science. Assuming that experience is fundamental, on the other hand, has not been shown to be logically necessary. One might claim that it shows promise, and I would disagree with them, but no one can say it has shown itself to be logically, scientifically, or explanatorily necessary. As was implied in our discussion of zombies, this addition of experience as a second fundamental makes Chalmers’ theory a sort of dualism. Dualism is, after all, the only way to conceive of Chalmers’ zombies in the first place. However, Chalmers wishes to distance himself from other forms of dualism because he does not believe there is anything spiritual or mystical about positing experience itself as a fundamental. Because of this, Chalmers argues that this sort of theory still follows the lines of any physical theory. Like a physical theory, it has “…a few fundamental entities connected by fundamental laws” (Chalmers, 15). The only difference is that this particular theory now contains non-physical experience as well as the physical world in its list of fundamentals. Chalmers calls this theory “naturalistic dualism.” However, this “naturalistic dualism” is still rather vague—let us see what we can do about that.
Because this new theory mirrors physical theories, Chalmers says that much of what it can say will be constrained by some of the same concepts that constrain physical theories. For Chalmers, a physical theory dictates that the “basic furniture” of the world is quite simple, and so we would expect a theory of consciousness that rests on fundamental principles in much the same way to do so as well. If this is the case, “[t]he principles of simplicity, elegance, and even beauty that drive physicists’ search for a fundamental theory will also apply to a theory of consciousness” (Chalmers, 15). There is a problem here in the fact that while physical objects are by their nature observable, this new non-physical—yet fundamental—“experience” is beyond the realm of observation. According to Chalmers, we can “observe” our own experience in some sense, but this is all we can really speak about; we can say nothing about others’ experience, because it goes unobserved. Chalmers then contends that all we can observe in others is the potential effects of experience on their behavior. However, this seems to contradict Chalmers’ contention that his zombies would appear exactly like normal people.
Given this, I am wary of calling this new theory “naturalistic dualism.” It seems to me, that for it to be naturalistic, experience would have to be identifiable in the natural world. Unfortunately, while we can point to physical objects in the natural world, it is not possible to point to “experiential objects.” This fact was argued years ago—and convincingly—by U.T. Place in “Is Consciousness a Brain Process?” However, Chalmers seems to think that we are able to observe our own experience to such a degree that we can say that it exists, and assume that others who act as we do might have it as well. The problem with this is that it requires the observer to observe itself. While this is not necessarily a problem, now that we have divided the observer into two fundamentally different parts whose relationship has not been explained, the ability of such an entity to “observe itself,” let alone be a cohesive entity at all, comes into question.
I can see two main ways to get out of this problem. One way, is to go off the dualist deep end and admit that there is no way to describe the relationship between experience and the physical. The other way of avoiding the problem involves heading in the opposite direction and taking experience to be something physical and token identified across multiple cognitive processes. If that were the case, a process, or more likely a group of processes, could be said to “observe” other processes as they played themselves out. We wouldn’t have a dualist stance anymore, but we’d at least be making sense. As I’m fairly sure Chalmers is unwilling to take the second option, I am left to assume he would rather take the first option and become a supernatural dualist—though I am not convinced there was ever such a thing as a “naturalistic dualist” in the first place.
Chalmers defends the lack of verifiability/falsifiability inherent in his theory by saying that the criteria we hold physical theories to will be quite enough to get us further down the road toward fully developing a new theory of consciousness despite our lack of observational data. These criteria include the standard theoretical virtues: “…simplicity, internal coherence, coherence with theories in other domains, the ability to reproduce the properties of experience that are familiar from our own case, and even an overall fit with the dictates of common sense” (Chalmers, 17). By using these criteria to judge his developing theory of consciousness, Chalmers believes we will arrive at “psychophysical principles” which will connect the physical and nonphysical aspects of his dualistic account of consciousness and experience (Chalmers, 17). However, given my previous critiques, explicating them would be a waste of time—we are better off moving on to the positive portion of this essay.
As I mentioned before, and as I have endeavored to show, Chalmers’ non-reductive account relies on his endorsement of the phenomenological fallacy—every criticism up to this point has dealt with the consequences of this endorsement. So, in presenting a competing theory it seems obvious that what we must do, above all, is avoid endorsing the phenomenological fallacy. With insights drawn from U.T. Place, Daniel Dennett, and Paul Churchland, this should not be too problematic. Having said that, I would like to propose a broad scientific methodology which, when applied, would lead us to an account of consciousness that allows us to talk meaningfully about the nature of consciousness from a reductive physical standpoint. This seems especially useful given that we have already seen how non-reductive accounts tend to fail.
Due to its scientific nature, such a methodology would have to lead us to questions that are capable of being tested—there can be no point at which observational data is impossible to attain. Now, this is not to say that every question we would be led to could be tested today—only that every question could, in principle, be tested given certain advances in cognitive science, and in the tools with which we study the brain. This means that when adhering to this methodology, there can be no resorting to the sorts of “additions” Chalmers claims are necessary to give an account of consciousness—if they’re not observable in principle, we can’t test them. Now, onto the methodology itself.
The first thing that any self-respecting account of consciousness ought to do is identify entities that are “conscious,” and this should be done as broadly as possible. We can always remove items from our list of conscious things, but it is much harder to add them (why this is will be made clear shortly). With this in mind, I believe the best way to go about identifying conscious entities is to endorse some version of Daniel Dennett’s intentional stance. The benefit of such a stance, aside from its ability to be applied broadly, is found in its usage of folk psychological terms. As much as folk psychological terms can cause confusion, we must not lose sight of the fact that it is exactly these terms we are asking about when we ask for an explanation of consciousness—‘consciousness’ itself is a folk psychological term, and so it makes sense to use folk psychological terms to help identify conscious things. However, we must also keep in mind that in searching for an explanation of the folk psychological term ‘consciousness’, we cannot point to actual folk psychological entities like “experience.” If the previous critique of Chalmers has done anything, it has shown that these supposed entities are unobservable, and unfit for a scientific study of consciousness.
If we are not going to turn to folk psychological entities, or “phenomenal objects” as Place calls them, what are we going to turn to? It seems we ought to turn to physical structures and their activities. As I said before, even if all preceding attempts to do this have failed, there is no reason to believe that further attempts will always continue to do so. The payoff of a reductive physical account, in terms of simplicity, internal coherence, coherence with theories in other domains etc., is well worth any risk. For the purposes of scientific investigation, folk psychological terms should be treated only as conceptual categories into which we place a wide variety of different physical phenomena—not as terms that apply to “actual” entities. Given this, once we have identified those things we are reasonably sure are conscious, we should approach them from an eliminative materialistic stance along the lines of Paul Churchland’s. Doing so allows us to say more accurately what is “conscious” and what is not, and allows us to avoid resorting to folk psychological objects in our explanation of consciousness. However, it should be noted that without first identifying those things which are said to be conscious, this would be an extremely limited explanation.
Here we can see more clearly why we ought to define and investigate consciousness in the broadest sense. If we stick solely to human consciousness, we are bound to make mistaken assumptions about the makeup of consciousness in the broad sense. How this might happen is rather obvious. For example, most people would say that their dog is conscious, but canine brains are significantly different from human brains—if we limit our analysis of consciousness to human consciousness, we are bound to come up with some organizational structures that do not exist in canine brains. If we were to then assume that human brains are the epitome of consciousness, we might be forced to say that dogs “cannot” be conscious because their brains have a different organizational structure from ours. So, if we are going to take a materialistic stance and hold that both humans and dogs are “conscious,” we must be on the lookout for those things that are common to both human and canine brains, and not limit ourselves to just human brains. “Conscious” is a term that applies to more than just humans, and we should seek it out wherever it can be found.
Putting this methodology into action in pursuit of subjective experience will yield results capable of addressing Chalmers’ “hard” problem of consciousness. If we wish to explain the “felt quality of redness” all we need to do is identify those entities that appear to “feel redness” and see what physical structures they hold in common. This could be accomplished by observing the brains of those entities when exposed to red objects. It is possible that in doing so we might find out that some entities cannot be said to “feel red” in the same way humans do despite their having the ability to perceive that wavelength of light. Given this result we might conclude that Chalmers is right in some sense and “awareness of red” does not always entail “feeling” or “experiencing” it. However, such a result would not mean that experience is non-physical, it would simply mean that “experience” it is not the same sort of physical thing as “awareness.”
With everything we’ve said up to now, we can easily see Chalmers’ conceptual additions for what they are: superfluous. The “water” of cognitive science is admittedly high in chlorine, but instead of purifying it, Chalmers adds a packet of metaphysical Kool-aid to it to mask its taste and get at the all-important “red” he’s looking for. Rather than admit that there is a legitimate physical method by which we can talk about “red,” Chalmers takes perfectly potable water and makes it into an over-sweet beverage, full of empty calories. Now that we have seen this addition of red 40 and sugar for what it is: a misstep caused by endorsing the phenomenological fallacy and an unnecessary diversion from traditional scientific method, we should be keen to avoid it. The question I kept avoiding—the question of whether David Chalmers is begging the question—is somewhat irrelevant at this point. However, why David Chalmers ever chose to embrace this metaphysical Kool-aid given the refreshing alternative is still somewhat of a mystery.
Chalmers, David J. “Facing up to the problem of consciousness.” Online Papers on Consciousness. Ed. David Chalmers & David Bourget. http://www.consc.net/papers/facing.html.
Place, U.T. “Is consciousness a brain process?” Mind and Cognition. Ed. William G Lycan & Jesse J. Prinz. Malden, MA: Blackwell Publishing Ltd, 2008. 25-30.