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Editorial Review Product Description
A look at how the mind works discusses computers, evolution, Descartes, Schro+a5dinger, the nature of perception, language, and individuality and ponders connections between psychology, physics, medicine, philosophy, and more. National ad/promo. ... Read more Customer Reviews (16) 
Fascinating Thesis Marred by Opaque and Overly Complex Exposition
Having read this book roughly twice, I'm still not sure I'm up to offering a review but that may, itself, be an important comment because clarity often reflects theoretical adequacy. The book's main thesis seems to boil down to this: Brains are a product of what Edleman calls selectional events, reflecting an operational principle specific to living systems. In this he draws a distinction at the very outset between the hit or miss outcomes of evolutionary development by random selection (which produce species differentiation by changing the individual members of species over time) and the instructional development people cause to happen via algorithms (step by step procedures for getting things done, either by describing the steps needed to get things done to one another, by following such steps, or by producing those steps in computational code which can then be translated into the digitized electronic signals we think of as 0's and 1's that govern computer operations).
Selection, of course, is serendipitous, whatever blueprint establishes each individual being the result of eons of trial and error in the selectional process that preceded it. Edelman takes this idea and applies it to how individual brains operate on a daily, and instant by instant, basis. Extending the idea of selection, as he has previously identified it in human immune systems (where antibodies in our bloodstreams selectively bond with invading agents, based on their "fit", and those which bond more closely out-produce those which don't, thus increasing the "right" type of antibodies in the bloodstream), Edleman suggests that the waxing and waning of the brain linkages (which, he claims, embody our mental processes) occurs in roughly the same way.
This is somewhat controversial because of 1) its implications (it challenges more accepted functionalist accounts which liken brain operations to algorithms such as those a computer can perform); and because of 2) its failure to fully account for how the selecting actually alters the strengths of the linkages or how the linkages themselves give us the features we associate with consciousness (things like awareness, intentionality, understanding, etc.). And yet, given that he has so thoroughly laid out his case for this kind of biological mechanism driving brains, and that he seems to have covered the obvious operational issues as they apply to what we presently know about brains, his thesis has a certain plausiblity. But it remains highly complex and even controversial because it boils down, in the end, to a number of somewhat abstruse and not intuitively apparent claims.
It's really all about memory in the end, Edelman says, though he defines this function so broadly that it's no longer recognizable as what we call memory in ourselves. Memory at its most basic level is the capacity of a self-contained, self-replicating system to retain changes and, via self-replication, to pass them on to descendent systems. Of course, "memory" also means the ability of a computational system to recover stored coded data and, in us, the ability to summon up past images, thoughts, associations, etc. Are these all the same thing? Edelman suggests they are and claims that it is the increasing systemic complexity and resultant sophistication that makes the primitive memory we find in relatively simple systems and their components (including the capacity to reproduce progeny with like "fits" as we find in immune systems) into the kinds of things we call memory in ourselves. It is this memory principle, a product of the selectionist dynamic (or perhaps the reason that selection manages to occur?) that, on his view, is the foundation of the kinds of features we recognize as consciousness in ourselves.
Alas, Edelman's thesis is anything but simple (which I'm guessing, is already apparent from my efforts here). In the end it seems to amount to the claim that brains, being organic and the result of the previously described selectional processes, are uniquely complex in structure and operation in the universe, each uniquely differentiated from all other brains (because even twins' brains, constructed on a shared blueprint, will have changed in their lifetimes in ways unique to each individual). It is this complexity of structure, this "morphology", he tells us, that is responsible for the things brains do. Consciousness, he argues, is built on levels of operation in the brain and primary or animal level consciousness (which itself has levels) forms the necessary foundation for higher level consciousness in which self-awareness and self-reflexiveness become possible. These levels are only possible because of the intrinsic complexity of brain morphology.
Edelman lays out a picture of how the different parts of the brain are responsible for different features and notes how many of the features we treat as unitary in ourselves (e.g., memory, perception, conception, etc.) may be best understood, upon reflection, to really be the result of the elaborate collaboration, through cross brain linking of neuronal groups in different brain centers responsible for different things. These combine to produce the various constituent operations that, when further joined through what he calls "reentrant loops", become the features we recognize in ourselves like awareness, understanding, remembering, intentionality, conceptualizing, believing, etc. He calls his model of how brains work, built on all of this, the Theory of Neuronal Group Selection (TNGS), because, he explains, different neuronal groups (not individual neurons) must operate together through the cross-brain linkages already mentioned to produce each instance of consciousness in ourselves. Such instances are thus complex occurrences and not the simple unified phenomena they appear to be on introspection.
Human memory, for instance, he describes as a complex phenomenon that differs from the relatively simple memory function which computers rely on. What we recognize as memory in ourselves is never exact, he points out, because it consists of a bunch of different linked constituent elements running in parallel and impinging on one another, albeit never exactly in the same way, each time a remembered item is summoned up. Unlike computational memory, which involves the exact replication of a coded instruction in each instance (a failure of this level of precision being a failure of the computational memory function), human memory is seen to be rough, approximate and ever-changing (think Roshomon or the related phenomenon of "false memory" as described by modern psychology). This feature of our memory happens because remembering in us is a function of a complex reconstruction process that depends on the relative strengths and linkages of the connecting loops between the implicated neuronal groups. As such this makes creativity and metaphor possible but it also means that each instance of recall introduces changes through new associations.
It's because of his claim that brains are uniquely complex (more like a jungle than a powerplant as he puts it) that he insists that computationalism, the thesis that consciousness can be replicated on computers, is unsound. We need brains he says, because consciousness is a biological product requiring the complex morphology and historical development, reflecting selection, that only organic systems can achieve. On this last point, though, I think he may well be mistaken.
Edelman often uses "consciousness" in a relatively unsophisticated way and seems to be under the impression that computations, as performed by computers, are purely abstract without, as John Searle (whom he cites) puts it, causal efficacy in the world. In fact, computers are as physically instantiated as brains and computational processes on computers as physical as they must be in human brains. But his answer as to whether a computer can be conscious does not stop with this claim about the abstract nature of computational processes. He makes the further point that computers, running on logic, are instructionally based whereas our brains, running on "selection", are not. In this he seems to disregard the notion that selection in evolution itself provides its own set of instructions (our genomes), even if they're not conceived in advance by any mind. Similarly he seems to overlook the obvious fact that the genetic mechanism, itself, appears to be a form of information processing just as computations in computers are (though genetic information processing may, in fact, be more complex).
Moreover, if what constitutes consciousness in us is a range of features which occur together (awareness, intentionality, understanding, perception, conception, etc.), then the real question is not whether brains and computers can accomplish the production of these features in the same way but whether they can both achieve the same functional output at all. If computers can produce the features we associate with consciousness, how they do it is likely to be less important than that they can and his argument that computers can never be expected to do what brains do would be wrong.
Nevertheless, he has offered a very compelling picture of the incredible complexity that confronts us (especially if you're a computationalist) in endeavoring to achieve the goal of creating synthetic minds. For Edelman, everything hinges on his argument for uniqueness and complexity, which he derives from the principle of selection that, he tells us, is unique to self-contained, self-perpetuating systems like living things. Computers, on the other hand, are pre-set operational functions ("syntactical" systems, again echoing another of Searle's famous criticisms) which are guided by an outside mind (the programmer) and therefore unable to react to an open-ended world of unpredictable and ever changing inputs. But in claiming this, he presumes that computers lack the ability to be open-ended because they are programmed though this is by no means clear -- or likely to be any truer than his related claim that consciously programmed computational machines are qualitatively different from organic machines that have evolved over eons as a result of a selectional mechanism. After all, does it really matter where the programming comes from, as long as there's programming there?
Edelman's underlying position is that the genetic programming of evolutionary selection leads to an open-ended tangle of unpredicted, and unpredictable, synaptic connections -- and their more macro neuronal group links which strengthen and weaken according to their ongoing interaction with external stimuli. It is this waxing and waning of the neuronal group pathways between the different brain centers and their sub-parts that gives rise to the facets of consciousness on his view -- an activity that is nothing like the computational processing of machines as found on computers.
Yet, in this he seems to be disregarding the fact that computational programs can also involve multiple sub-systems doing different, interrelated things, and that such systems can be designed to implement open-ended reactions to an unpredicted world of stimuli once basic parameters are set. Such parameters need be no more obtrusive than our own evolution-driven genetic codes, after all.
Edelman's thesis is worth thinking about and may well offer some interesting directions for understanding how brains work and for developing new thinking machines that may depart from the standard computational model we rely on today (the universal Turing machine). Unfortunately Edelman's writing is not up to the level of the ideas presented (on my view).It may be the case that the complexity of Edelman's thesis would not admit of any more succinct or precisely written text than he has provided but, in spite of my own difficulties here in explicating his ideas, I rather think he could have (and should have) been clearer. Certainly his failure to be clear is at least a prima facie reason to question the potency of the underlying ideas.
SWM
Brilliantly Sobering
This book is my introduction to Dr. Edelman, and I was stunned.Yes, I understand that this is a synopsis of his overall trilogy, and I am thankful for that.Now I can go to those volumes to dig deeper, if I don't move on to more recent works.I read this as a result of a recommendation in response to someone reviewing Steven Pinker's How the Mind Works (see my review of of that, if they'll print it).Edelman is clear, concise, and informative (and I like his wry humor).He shows all the marks of a great teacher, especially by patiently walking us through the tough neurologic stuff.I call this review Brilliantly Sobering because, once I had absorbed and understood his Theory of Neuronal Group Selection, the whole thought process business (and evolutionary and developmental progression of same) made sense for a change (unlike with Pinker's lame computational analog), and that actually startled me into thinking about HOW I think (and then, as a result, how I act -- what a change of pace for a student of Buddhism).Like I said, sobering.So next thing I did was pick up a copy of The Symbolic Quest: Basic Concepts of Analytical Psychology by Edward C. Whitmont (highly recommended) to help figure out WHY I think the way I think.Anyway, thank you, Dr. Edelman, I look forward to following you to where you've gone next.Meanwhile, I think I think I'll have a beer.
evolutionary mindbrain
Very dense, although I understand this is one of the easiest of this author's output to get through.Also made somewhat uneasy by author's slam-bang insistence on the Darwin evolutionary development of the mindbrain,which of course is the thrust of his thesis, to the exclusion of most other possibilities.Edelman has an answer, but not ALL of the answer and his one-sidedness puts me off I guess. Difficult to read, basically.
Consciousness as a biological Darwinist adaptation.
This is a very important book.
It proves convincingly that consciousness is a matter of ... matter (the biological matter of the brain) and that it is the outcome of a long history of biological adaptations. It also proves that the mind is not a computer or a Turing machine, that human language is not a computer language and that physics is not sufficient to explain its working. The morphology of the brain goes deep, but not as deep as to attain the quantum level.
On the contrary, Edelman explains clearly that the mind is a process that operates in a 4 dimensional world; that it doesn't have a perfect memory or doesn't order events or objects logically. It is subject to mutation in order to select and to adapt and creates itself aspects of the reality by cultural and language interaction. Into the bargain, the biological structure of the brain is different for every individual. Edelman's theory has also far reaching philosophical implications. It is the death of essentialism (there are no 'essences', only populations with different individuals) and of idealism (the world was there before the mind). Is Edelman's TNGS (theory of neural group selection) the end of the story? Absolutely not. It is only the beginning. It forms the basis for further investigations. But it clearly indicates which way to follow and which ways not. I have only one reservation: Edelman's nearly unconditional admiration for Freud. This is an essential read.
a bit watered-down
I am a huge fan of Edelman, but I regretted having bought this book; I would say this is a kind of half-successful attempt at vulgarizing what he explained so well elsewhere: there is nothing to be found here that wasn`t already explained in more detail in "Neural Darwinism" and "The Remembered Present". So stay away from this one if you read the others. If you never read anything by him, go for his "Neural Darwinism". Reading his books was definitely a great intellectual experience of my life. Go for it!
PS: Da man is a genius.
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