Wider Than the Sky is Gerald Edelman‘s summary/overview of his work on the neural basis of consciousness. (Parts of this work have been explained, in greater detail, in a number of Edelman’s earlier books; the ones I have previously read are Bright Air, Brilliant Fire and The Remembered Present).
Edelman has a peculiar position in neuroscience, from what I have been able to gather: he is disliked by many because of his egocentric insistence on reinventing the wheel. That is to say, he insists so unilaterally on his own theories that he ignores work by others that in many ways is parallel to his, and that his own work would benefit by communicating with.
Be that as it may, Edelman offers an interesting and plausible (albeit largely unproven) theory about how consciousness is generated, and how it works, in the brain. His basic thesis is the hypothesis of “neural Darwinism”: he argues that both the growth and “wiring” of neurons during fetal and childhood development, and the activation of neurons in memory and in response to the environment are governed by a process analogous to Darwinian natural selection. (Edelman previously won the Nobel Prize for his work showing that such selection mechanisms were at work in the mammalian immune system, as populations of antibodies mutate and grow in response to infections). Groups of neurons are selected on the basis of their effectiveness in responding to multiple stimuli from the outside world, and in classifying and responding to these stimuli in terms of categories derived from previous, remembered experiences (what Edelman calls “value-category memory”). Consciousness arises as a result of “reentry”, a kind of hyper-feedback among groups of neurons allowing for coordination among, and unification of, what would otherwise be disconnected percepts. (Edelman defines reentry as “the dynamic ongoing process of recursive signaling across massively parallel reciprocal fibers…” Such a process “allows coherent and synchronous events to emerge in the brain.” These events are the contents of consciousness, and processes of reentry explain how consciousness can be both unified, and yet extremely diverse and continually changing).
There are many more details, involving such things attention, emotion, and the difference between “primary consciousness,” which presumably all mammals and birds have, and “higher-order consciousness” (or what I would call reflexive consciousness, or self-consciousness) which only really emerges with language (though Edelman allows for the possibility that cruder, emergent versions of it may exist among the great apes).
A lot of this would seem to be speculation; a lot of it isn’t really experimentally grounded (at least so far), and some of it may in fact not be ‘scientific’ at all, because not empirically testable or falsifiable.
But to my mind, this is not necessarily a deficiency. Though Edelman throughout expresses his admiration for, and frequent agreement with, the psychology of William James, he begins the book by disclaiming any metaphysical intent, and by expressing puzzlement over James’ claim that, when consciousness finally is explained, “the necessities of the case will make [these explanations] ‘metaphysical'” (Edelman quoting James in his Preface, page xii).
It seems to me that, even in spite of himself, Edelman proves James right, by giving a theory of consciousness that is to some extent unavoidably metaphysical. Edelman shies away from such a term because he insists, rightly, that in any explanation of consciousness “principles of physics must be strictly obeyed and that the world defined by physics is causally closed. No spooky forces that contravene thermodynamics can be included” (page 114). –But I think that James himself would have entirely accepted this qualification, and that what he meant by “metaphysical” is something else. A theory of consciousness can’t help being “metaphysical,” because it’s impossible to “translate” between first-person phenomenal sensation, and third-person, scientifically objective observation. The point, precisely, is to do “metaphysical” justice to first-person consciousness, without thereby positing its objective existence as a phenomenon in the world (which would mean believing in “spooky forces” like “spirit” or “mind energy” or something else extra-physical).
Edelman’s theory of consciousness is “metaphysical” in what I consider the good, Jamesian sense, because his way of finessing the difference between observable-from-outside neural states and inside-only conscious feeling is to reject both those theories that would give causal efficacy to consciousness and will and those theories that dismiss consciousness as “merely” epiphenomenal. In effect, Edelman is saying that consciousness is indeed epiphenomenal rather than actually causal, but that there is nothing “mere” about such epiphenomenality. This latter because consciousness is “entailed” by neural processes that are themselves causal (which could perhaps be read — though I am unsure that this is right — as a weak version of Spinoza’s mind/body parallelism).
So far I’ve left out what is perhaps the most important part of Edelman’s theory: the assertion that neural processes are massively “degenerate” (a better word, in terms of vocabularies that I am familiar with, would be “redundant”). (Edelman defines “degeneracy” as “the ability of different structures to carry out the same function or yield the same output”). This is something that does seem to be empirically valid (different neural pathways can result in the same emotion or memory or other conscious perception; if one particular brain system or sub-system breaks down, another one can ‘cover’ for it or adaptively take its place), and that is logically coherent with (and indeed necessitated by) the assumption of “neural Darwinism” (if mind states are the result of statistical selection among large populations of neurons, then there cannot be one and only one uniquely privileged pathway to generate a given result).
What’s crucial here is that, if we accept the “degeneracy”/redundancy of the brain operating by this sort of “selection,” then “much of cognitive science is ill-founded” (page 111): the brain does not operate algorithmically (as Daniel Dennett claims), or by a process of computation analogous to what goes on in digital computers. Thought is not a process of taking symbolic representations and performing calculations, or logical operations, upon them. There is no “language of thought” (page 105), of which actual language would merely be a “translation.”
Thus, though Edelman shows no signs of being aware of the anti-representationalist arguments in recent continental philosophy and “theory”, he comes to many of the same conclusions, in opposition to the reigning (in American psychology and computer science, at least) ideology of cognitivism. And he does this by being a better Darwinian than all those loudly and explicitly Darwinian “evolutionary psychologists” who are so willfully dismissive of neuroscience.
Wider Than the Sky
Wider Than the Sky is Gerald Edelman‘s summary/overview of his work on the neural basis of consciousness. (Parts of this work have been explained, in greater detail, in a number of Edelman’s earlier books; the ones I have previously read are Bright Air, Brilliant Fire and The Remembered Present).
Edelman has a peculiar position in neuroscience, from what I have been able to gather: he is disliked by many because of his egocentric insistence on reinventing the wheel. That is to say, he insists so unilaterally on his own theories that he ignores work by others that in many ways is parallel to his, and that his own work would benefit by communicating with.
Be that as it may, Edelman offers an interesting and plausible (albeit largely unproven) theory about how consciousness is generated, and how it works, in the brain. His basic thesis is the hypothesis of “neural Darwinism”: he argues that both the growth and “wiring” of neurons during fetal and childhood development, and the activation of neurons in memory and in response to the environment are governed by a process analogous to Darwinian natural selection. (Edelman previously won the Nobel Prize for his work showing that such selection mechanisms were at work in the mammalian immune system, as populations of antibodies mutate and grow in response to infections). Groups of neurons are selected on the basis of their effectiveness in responding to multiple stimuli from the outside world, and in classifying and responding to these stimuli in terms of categories derived from previous, remembered experiences (what Edelman calls “value-category memory”). Consciousness arises as a result of “reentry”, a kind of hyper-feedback among groups of neurons allowing for coordination among, and unification of, what would otherwise be disconnected percepts. (Edelman defines reentry as “the dynamic ongoing process of recursive signaling across massively parallel reciprocal fibers…” Such a process “allows coherent and synchronous events to emerge in the brain.” These events are the contents of consciousness, and processes of reentry explain how consciousness can be both unified, and yet extremely diverse and continually changing).
There are many more details, involving such things attention, emotion, and the difference between “primary consciousness,” which presumably all mammals and birds have, and “higher-order consciousness” (or what I would call reflexive consciousness, or self-consciousness) which only really emerges with language (though Edelman allows for the possibility that cruder, emergent versions of it may exist among the great apes).
A lot of this would seem to be speculation; a lot of it isn’t really experimentally grounded (at least so far), and some of it may in fact not be ‘scientific’ at all, because not empirically testable or falsifiable.
But to my mind, this is not necessarily a deficiency. Though Edelman throughout expresses his admiration for, and frequent agreement with, the psychology of William James, he begins the book by disclaiming any metaphysical intent, and by expressing puzzlement over James’ claim that, when consciousness finally is explained, “the necessities of the case will make [these explanations] ‘metaphysical'” (Edelman quoting James in his Preface, page xii).
It seems to me that, even in spite of himself, Edelman proves James right, by giving a theory of consciousness that is to some extent unavoidably metaphysical. Edelman shies away from such a term because he insists, rightly, that in any explanation of consciousness “principles of physics must be strictly obeyed and that the world defined by physics is causally closed. No spooky forces that contravene thermodynamics can be included” (page 114). –But I think that James himself would have entirely accepted this qualification, and that what he meant by “metaphysical” is something else. A theory of consciousness can’t help being “metaphysical,” because it’s impossible to “translate” between first-person phenomenal sensation, and third-person, scientifically objective observation. The point, precisely, is to do “metaphysical” justice to first-person consciousness, without thereby positing its objective existence as a phenomenon in the world (which would mean believing in “spooky forces” like “spirit” or “mind energy” or something else extra-physical).
Edelman’s theory of consciousness is “metaphysical” in what I consider the good, Jamesian sense, because his way of finessing the difference between observable-from-outside neural states and inside-only conscious feeling is to reject both those theories that would give causal efficacy to consciousness and will and those theories that dismiss consciousness as “merely” epiphenomenal. In effect, Edelman is saying that consciousness is indeed epiphenomenal rather than actually causal, but that there is nothing “mere” about such epiphenomenality. This latter because consciousness is “entailed” by neural processes that are themselves causal (which could perhaps be read — though I am unsure that this is right — as a weak version of Spinoza’s mind/body parallelism).
So far I’ve left out what is perhaps the most important part of Edelman’s theory: the assertion that neural processes are massively “degenerate” (a better word, in terms of vocabularies that I am familiar with, would be “redundant”). (Edelman defines “degeneracy” as “the ability of different structures to carry out the same function or yield the same output”). This is something that does seem to be empirically valid (different neural pathways can result in the same emotion or memory or other conscious perception; if one particular brain system or sub-system breaks down, another one can ‘cover’ for it or adaptively take its place), and that is logically coherent with (and indeed necessitated by) the assumption of “neural Darwinism” (if mind states are the result of statistical selection among large populations of neurons, then there cannot be one and only one uniquely privileged pathway to generate a given result).
What’s crucial here is that, if we accept the “degeneracy”/redundancy of the brain operating by this sort of “selection,” then “much of cognitive science is ill-founded” (page 111): the brain does not operate algorithmically (as Daniel Dennett claims), or by a process of computation analogous to what goes on in digital computers. Thought is not a process of taking symbolic representations and performing calculations, or logical operations, upon them. There is no “language of thought” (page 105), of which actual language would merely be a “translation.”
Thus, though Edelman shows no signs of being aware of the anti-representationalist arguments in recent continental philosophy and “theory”, he comes to many of the same conclusions, in opposition to the reigning (in American psychology and computer science, at least) ideology of cognitivism. And he does this by being a better Darwinian than all those loudly and explicitly Darwinian “evolutionary psychologists” who are so willfully dismissive of neuroscience.