In Neither Brain nor Ghost, Rockwell presents a clear and compelling argument for why it is time to replace our outdated and philosophically problematic notions of mind with a more promising conceptualization of mind as a behavioral field that emerges from the dynamic interaction of brain, body, and world. Drawing on historical and contemporary references that offer (albeit sometimes indirect) support for his view, Rockwell argues that although the need to revise our notion of mind has been intermittently acknowledged in various subdisciplines in philosophy, the nontraditional concept of mind as a brain-body-world nexus merits full consideration if we are to make any real scientific and philosophical progress in our understanding of the mind. Accordingly, I would put this book on the reading list of those working in philosophy of mind, consciousness, cognitive science, artificial intelligence, and perhaps psychology. The book would be an excellent source for a progressive graduate seminar in any of these areas.
In the book, Rockwell draws on the philosophy of John Dewey to generate a pragmatist alternative to the philosophical gridlock generated by eliminative materialism and functionalism that characterized much of twentieth-century philosophy of mind. Two principles of Dewey's philosophy are most important to Rockwell's project: (1) a general wariness toward imposing dichotomies between mind and body, mind and brain, or organism and environment; and (2) an appreciation of experience as a continuous, purposive, intentional whole.
In accordance with the first principle, Rockwell rejects what he calls ‘Cartesian materialism’, a view that emphasizes not only the mind-body, but also the brain-body distinction. I agree with Rockwell's observation that although most philosophers today have abandoned substance dualism, subtler forms of Cartesianism still haunt contemporary discussion on the nature of mind; this point is perhaps best exemplified by thought experiments depicting various scenarios of disembodied conscious experience that work only within the assumption that it is coherent to talk about minds being separated from bodies. Rockwell offers a refreshing antidote to this old habit in philosophy of mind in a variety of novel and purportedly scientifically implementable thought experiments designed to test the intuitions of the brain-body-world nexus. He also revisits several well known thought experiments (e.g., Putnam's ‘Twin Earth’, Dennett's ‘Where Am I?’, and Chalmers’ zombies) and offers original replies to them.
The second principle, i.e., that experience must be understood holistically, is essential to Rockwell's conclusion that dynamic systems theory (DST) is a promising tool for generating the scientific content of the brain-body-world nexus. (Readers who are wholly unfamiliar with DST might do well to read Chapter 10 early on, wherein a good introduction to the theory is given.) Rockwell's bold move is to abandon the traditional conceptualization of mind as a self-contained mechanism wherein bits of information about the external world slowly accumulate—which invites problems associated with mental representation and skepticism—and instead propose that the mind is the sum total of dynamic interactions among brain, body, and world. Rockwell believes this shift in philosophical perspective accounts for both the failure of early efforts in artificial intelligence that attempted to model the whole world inside of a computer, and the more recent successes of connectionist networks that have no need to do so. Rockwell thinks the major advantage of employing DST in both cognitive science and artificial intelligence is the theory's ability to describe such systems in terms of processes rather than particulars.
An important point that is repeated throughout the book is that, if asked which organ in the body is responsible for conscious experience, it would be easy to undermine any response other than the brain. But, Rockwell insists, this is the wrong question to ask, or rather, a leading question with only one ‘right’ answer. Rockwell gives a careful account that spans several chapters of the book of why it is wrong to assume that because brain events co-occur with mental experience, they are therefore solely responsible for mental experience. A wealth of data from experiments in neuroscience suggests that the brain is hormonal as well as neural and that the entire nervous system is in some sense cognitive. Rockwell agrees that the mind supervenes on something physical, but disputes the claim that the brain is the sole supervenience base; instead, he argues that the mind supervenes not on the connections between neurons in the brain, but on the causal relations between brain, body, and world.
In the penultimate chapter of the book, Rockwell presents a pragmatist alternative to the Cartesian dichotomy holding that illusions are a product of the mind while veridical experience is a product of reality. Instead, Rockwell's pragmatist version of empirical adequacy holds that since experience emerges from interactions between perceptual space and behavioral space, error arises not from having a theory that cannot reach outside the head, but rather because the theory refers to the world in a confused or equivocal manner. In sum, the best scientific theories are those that allow us to function in the world effectively.
I recall my first reading of Heidegger's Being and Time as encountering a series of undeniable philosophical insights. It is not too much of a stretch to say that Rockwell's new book produces a similar effect and for much the same reason—Neither Brain nor Ghost provides a salient account of where philosophy of mind went wrong and offers a promising approach to get it back on track. Reading Rockwell's account has the profound effect of dissolving the self-world divide to allow a new metaphor to emerge—that of dynamically interacting concentric circles of nervous system, body, self-world, and the broader reality. This book is an essential read for those interested in the nature of mind; for those of us already sympathetic to the project, the book enriches the view with historical antecedents from some unlikely places and offers a progressive scientific program for how to explore the new view of mind empirically.
