Tucson, we have a problem. In Explaining Consciousness: The Hard Problem, edited by Jonathan Shear, the riddles and perplexities of consciousness are knocked back and forth over the course of some twenty-eight articles and more than four hundred pages. The collection is focused on a keynote article written by David Chalmers delineating the so-called "hard problem of consciousness." Many of the usual suspects from the ever-expanding literature on consciousness (and from the Tucson "Towards a Science of Consciousness" conferences) are featured here, including Daniel Dennett, Patricia Churchland, Colin McGinn, Francis Crick, and, of course, Chalmers himself. But although the book presents a broad spectrum of current views on consciousness, it is flawed because it imparts too much information with too little editorial structure and guidance. We get a taste of everyone’s favorite theory of consciousness, but a lack of real depth and debate. In what follows, I’ll provide a brief sketch of the articles in the collection, and I’ll close with some comments on the work’s organization and content.

The book opens with Chalmers’ keynote paper. Chalmers holds that while some mental phenomena can be understood functionally or structurally, the subjective character of conscious experience can’t be captured in this way. The phenomenal nature of experience appears to be a nonfunctional, intrinsic aspect of the mind. And because we can’t get at this sort of property in the usual scientific manner, we are left with a deep question. Why should a device that functions this way have conscious experiences at all? A correlation of neural processes with conscious experience only provides a contingent connection of function and experience, a connection that doesn’t provide a satisfactory explanation of why we are conscious. This is the "hard problem of consciousness." Chalmers sketches a nonreductive solution to the problem, positing omnipresent, basic information as the foundation of consciousness, and describing various correlational laws constraining the connections between information, functional structure, and consciousness.

The responses open with papers taking "deflationary perspectives" on the problem. Daniel Dennett and Patricia Churchland both argue that Chalmers’ position is analogous to the vitalist’s position in biology. Once the proper functional characterization of the mind is in place, Chalmers’ view will be undermined, just as mechanism in biology undermined vitalism. Thomas Clark argues that Chalmers’ initial assumption that consciousness "emerges" or "arises" out of neural processes imposes an artificial separation between consciousness and the brain. This separation creates the hard problem, and should be resisted. Valerie Hardcastle contends that explaining consciousness just is a matter of uncovering the appropriate correlations between function and phenomenology, so the hard problem is a "non-issue for materialists" (61). Kieron O’Hara and Tom Scutt hold that proper scientific questions have potential solutions, while the very formulation of the hard problem makes it insoluble. Thus, it is not a worry for a scientific psychology. Finally, Mark Price asks whether we should ever expect to feel satisfied by an explanation of consciousness, given the centrality of experience to our perspective on the world, and the nature of concepts and explanatory theories. But this is not a deep metaphysical problem calling for a radical revision of science.

The second section focuses on the alleged "explanatory gap" that exists between our first- and third-person understandings of consciousness. Colin McGinn considers the apparently nonspatial nature of the mental, and argues that this aspect of the mind can’t be explained by us, due to the limits of our biological makeup. Eugene Mills agrees with Chalmers that consciousness doesn’t fit into the standard explanatory framework of science, but he argues that even Chalmers’ nonreductive theory fails to shed any light on the matter. In separate pieces, E.J. Lowe and Douglas Hodgson argue that Chalmers has underestimated the difficulties involved in explaining the mind. They hold that there are no "easy problems" in the mind, because consciousness is intimately involved in all processes that deserve the title "mental." Richard Warner claims that the central problem of the mind is explaining its "qualified incorrigibility," the mind’s capacity to work with an uncanny effectiveness that defies mechanistic explanation. The solution, Warner argues, requires abandoning the idea that physics is a closed, explanatorily adequate body of knowledge. To close the section, William Robinson offers his own detailed analysis of the hard problem. He argues that the problem can’t be solved because consciousness does not possess a decomposable structure. In the absence of such a structure, we can’t break down the phenomenon in a manner that allows for a satisfying explanation.

The third section of the book contains papers suggesting that insights from quantum physics are relevant to the study of consciousness, and that the mysteries of both fields are intimately connected. C.J.S. Clarke contends that the apparent nonlocality of the mental can be explained by invoking explanations of nonlocality in modern physics. Stuart Hameroff and Roger Penrose argue that consciousness is tied to the "orchestrated objective reductions" (189) that generate the classical world of macroscopic objects out of quantum physics. Furthermore, microtubules in the brain’s neurons act to coordinate this quantum activity, creating the nonmechanistic human mind. In separate articles, Henry Stapp and Douglas Bilodeau contend that subjective awareness is present even at the bottom level of quantum physics, and acknowledging this fact can help explain the apparently nonmechanistic features of human thought.

The papers in the next section come from Neuroscience and Cognitive Science. Francis Crick and Cristof Koch argue that neuroscience may indeed be able to explain consciousness, and that we should investigate in detail those processes associated with conscious experience. Furthermore, the apparent privacy of the mental is what we should expect, given the various ways that the brain encodes information. Bernard Baars holds that consciousness arises when information is processed in what he calls a "global workspace" (241). Information in the global workspace is coded in such a way that it is available to a variety of systems distributed throughout the brain. By focusing on the contrast between conscious and nonconscious processes, we should be able to isolate the important features of the global workspace, thus explaining consciousness. Bruce MacLennan closes the section by suggesting that we employ the techniques of philosophical phenomenology to isolate the fundamental units of subjective experience. These units can then be matched up in a close correspondence with neural processes. This is not intended to reduce experience to neural activity; rather, neuroscience and phenomenology working together can provide a satisfying account of the conscious mind.

The last two sections of the book present arguments suggesting that we may need to alter our scientific worldview in order to accommodate consciousness. William Seager argues that, though panpsychism, the idea that all things are conscious to some degree, seems unpalatable, there are no real knock-down arguments against the position. Given the difficulty of the hard problem, such a view may be forced upon us. Gregg Rosenberg’s paper presents additional positive arguments for panpsychism. Benjamin Libet cites his own research on the brain in support of the difficulty of the hard problem. He is critical, however, of Chalmers’ proposed solution involving fundamental information and laws that dictate how that information is related to functional structures. Piet Hut and Roger Shepard propose that we "turn the hard problem upside down and sideways" (305). By making experience basic, we can switch the focus of the hard problem. Rather than accounting for experience in the natural world, we should attempt to explain the emergence of the objective world from experience.

In the final section, Max Velmans argues that a full appreciation of the primacy of experience mandates a nonreductive theory of consciousness. He posits experience as an aspect of a more basic stuff underlying both the objective and the subjective world. Francisco Varela contends, like Bruce MacLennan, that an adequate explanation of consciousness requires a synthesis of the methods of neuroscience and philosophical phenomenology. The section closes with a piece by Jonathan Shear. Shear argues that not only should we employ phenomenology in the investigation of consciousness, but we should use the techniques of eastern religions, including meditation, to isolate the basic features of experience.

The book ends with a response by Chalmers. Against the deflationist position, he argues that the hard problem is importantly unlike previous scientific conundrums. The vitalism/mechanism debate in biology was settled once an adequate account of the relevant functions and structures was produced. But, Chalmers contends, even a complete functional description of the mind will leave the hard problem unanswered. In response to criticisms of his positive proposals, Chalmers admits that his claims are highly speculative. But he maintains that his ideas are open possibilities, and offers them as suggestions for further investigation. Chalmers closes with a brief review of the various positive suggestions offered by others, but he provides little insight beyond a positive assessment of the direction and vitality of the research.

To reiterate, I found the book disappointing, because it provides both too much information, in the sheer number and variety of articles presented, and too little information, in the cursory nature of the particular papers themselves. The book also suffers from a paucity of unifying or summarizing material provided by the editor. It would have been very helpful to have some assistance in grouping and processing such a large amount of data. Finally, I think that many of the articles may be too esoteric for the lay reader to approach. Philosophers of mind and cognitive scientists will find some familiar material, but even they may be at sea on some of the topics presented, and there is not a lot of overlap, making it difficult to fully engage all the material.

It also seems to me that the very book itself may constitute an argument for the deflationist position. Given the wildly divergent and radically revisionary nature of many of the responses, we should go back and consider if consciousness might not be a functional feature of the mind after all. Indeed, this is the crucial question that divides those who accept and those who deny the presence of a hard problem. How does Chalmers know that consciousness is not functional feature of the mind? Does his own experience really deliver this fact to him? One can deny this without falling into an eliminativism about consciousness. Consciousness may be functional, but it just may not seem that way to us, from the first-person point of view. Given the alternatives presented in the book, I believe that it’s a good idea to pursue this possibility until we are really sure it’s wrong.

© Josh Weisberg 2001