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Consciousness
The problem of consciousness was hardly avoidable for someone like me, who has spent most of his scientific life working on mechanisms of vision. That is by now a very active field, with thousands of workers. We have learned a lot, and expect to learn much more; yet none of it touches or even points however tentatively in the direction of telling us what it means to see.
I learned my business on the eyes of frogs. The retina of a frog is very much like a human retina. Both contain two kinds of light receptors, rods for vision in dim light and cones for bright light; the visual pigments are closely similar in chemistry and behavior; both have the same three fundamental nerve layers, and the nervous connections to the brain are much alike. But I know that I see. Does a frog see? It reacts to light -- so does a photocell‑activated garage door. But does it know it is responding, is it aware of visual images?
There is nothing whatever that I can do as a scientist to answer that question. That is the problem of consciousness: it is altogether impervious to scientific approach. As I worked on visual systems -- it would have been the same for any other sensory mode, let alone more subtle or complex manifestations of mental activity -- this realization lay always in the background. Now for me it is in the foreground. I think that it involves a permanent condition: that it never will become possible to identify physically the presence or absence of consciousness, much less its content.
I of course have some preconceptions, but the only unequivocally sure thing is what goes on in my own consciousness. Everything else that I think I know involves some degree of inference. I have all kinds of evidence that other persons are conscious. It helps that they tell me so, and display other evidences of consciousness in speech and writing, art and technology. I believe that other mammals are conscious; and birds -- that business of singing at dawn and sunset makes me think that they are essentially poetic creatures. But when I get to frogs I worry, and fishes even more so. Those animals at least respond reasonably to light and some visual images. But I have worked also on the numerous and anatomically magnificent eyes of scallops, without finding any indication that these animals see, beyond reacting to a passing shadow. The last animals whose vision I worked on with my own hands were worms with great big bulging eyes, with everything you could ask for in an eye. The eyes yielded fine electrical responses to light, but I never could get the worms themselves to give any indication whatever that they responded to light. Maybe they didn’t like being with me.
Any assumption regarding the presence or absence of awareness in any nonhuman animal remains just that: an unsupported assumption. Matters are no different with inorganic devices. Does the photoelectrically activated garage door resent having to open when a car’s headlights shine on it? I think not. Does a computer that has just beaten a human opponent at chess feel elated? I believe not. But there is nothing I can do to shore up those assumptions either.
Consciousness is not part of that universe of space and time, of observable and measurable quantities, that is amenable to scientific investigation. For a scientist, it would be a relief to dismiss it as unreal or irrelevant. I have heard distinguished scientists do both. In a discussion with the physicist P. W. Bridgman some years ago, he spoke of consciousness as “just a way of talking.” His thesis was that only terms that can be defined operationally have meaning; and there are no operations that define consciousness. In the same discussion, the psychologist B. F. Skinner dismissed consciousness as irrelevant to science, since confined to a private world, not accessible to others.
Unfortunately for such attitudes, consciousness is not just an epiphenomenon, a strange concomitant of our neural activity that we project onto physical reality. On the contrary, all that we know, including all our science, is in our consciousness. It is part, not of the superstructure, but of the foundations. No consciousness, no science. Perhaps, indeed, no consciousness, no reality -- of which more later.
Though consciousness is the essential condition for all science, science cannot deal with it. That is not because it is an unassimilable element within science, but just the opposite: science is a highly digestible element within consciousness, which includes science as a limited territory within the much wider reality of whose existence we are conscious. Consciousness itself lies outside the parameters of space and time that would make it accessible to science, and that realization carries an enormous consequence: consciousness cannot be located. But more: it has no location.
Some years ago I talked about this with Wilder Penfield, the great Canadian neurosurgeon. In the course of his therapeutic activities he had unprecedented opportunities to explore the exposed brains of conscious patients, and hoped in this way to discover the seat of human consciousness. I asked him, “Why do you think consciousness is in the brain? Maybe it’s all over the body.”
He chuckled, and said, “Well, I’ll keep on trying.”
About two years later, I met him again and he said to me, “I’ll tell you one thing: it’s not in the cerebral cortex!”
Shortly afterward came the exciting announcement that the so‑called reticular formation in the brain stem of mammals contains an arousal center, a center that seems to wake creatures up and produce awareness. The problem with all such observations is that one cannot know whether one is dealing with a source or with part of the machinery of reception and transmission. It is as though, finding that the removal of a transistor from a television set stopped the transmission, one concluded it to be the source of the program.
How could one possibly locate a phenomenon that one has no means of identifying -- neither its presence nor absence -- nor any known parameters of space, time, energy exchange, by which to characterize merely its occurrence, let alone its content? The very idea of a location of consciousness is absurd. Just as with Heisenberg’s uncertainty principle, we have more to deal with here than technical inadequacy, with a perhaps temporary lack of means of observation and measurement. What we confront is an intrinsic condition of reality. It is not only that we are unable to locate consciousness: it has no location.
Consider pain, the most primitive of sensory responses, and most closely connected with survival. I have had to kill many animals in the course of my work, and have tried always to inflict a minimum of pain. But do other animals than man feel pain? Many physiologists assert that only warm‑blooded animals feel pain, and some of their publications have stated this as an official view. The National Eye Institute announced only in 1979 a first break with this position, asking workers with cold‑blooded animals to try to avoid giving them “unnecessary pain.” When I lop off the head of a frog, I assume that the headless body is beyond pain; but is the head? So I hastily destroy the brain, and hope that ends the problem. Yet I have heard Wilder Penfield say that once a human brain has been exposed, one could operate on it with a spoon without causing an unanesthetized patient any great discomfort. And what of a worm, any small piece of which writhes on being pinched?
Recently there has been a controversy in the American press involving some physicians having asserted that a human fetus feels pain in an abortion. The very idea should raise deep concern about the very widespread Arnerican practice of circumcising male newborns, performed routinely without anesthesia, the physicians having assured the rnothers that the nervous systems of their infants have not yet developed sufficiently for them to feel pain. All such assertions are equally groundless. Even as regards so primitive a concept as pain, we are altogether baffled in trying to substantiate its occurrence or absence.
I used to show students a film made by the French zoologist Faure‑Fremiet on the feeding behavior of protozoa. Many of our sturdiest concepts of the apparatus required for animal behavior are mocked by these animalcules, particularly by the ciliates; for in one cell they do everything: move about, react to stimuli, feed, digest, excrete, on occasion copulate and reproduce. In this film one saw them encountering problems and solving them, much as would a mammal. I remember best a carnivorous protozoon tackling a microscopic bit of muscle. It took hold of the end of a fibril, and backed off at an angle, as though to tear it loose. When the fibril would not give, the protozoon came in again, then backed away at a new angle, worrying the fibril loose, much as a dog might have done, worrying loose a chunk of meat. It was hard, watching that single cell at work, not to anthropomorphize. Did it know what it was doing?
But then, ciliate protozoa are the most complex cells we know. How about a cell highly specialized to perform a single function in a higher organism, a nerve cell for example, that can only transmit an impulse? Once, years ago, I was visiting the invertebrate physiologist, Ladd Prosser, at the University of Illinois in Urbana. He took me into his laboratory, where he was recording the electrical responses from a single nerve cell in the ventral nerve cord (which takes the place of our spinal cord) of a cockroach. It was set up to display the electrical potentials on an oscilloscope screen, and simultaneously to let them sound through a loudspeaker. I was hearing a slow, rhythmic reverberation, coming to a peak, then falling off to silence, then starting again, each cycle a few seconds, like a breathing rhythm. Prosser remarked, “That kind of response is typical of a dying nerve cell.”
“My God!” I said, “It’s groaning! You’ve given it a voice, and it’s groaning!”
Was that nerve cell expressing a conscious distress? Is something like that the source of a person’s groaning? There is no way whatever of knowing.
So that is the problem of mind -- consciousness -- a vast, unchartable domain that includes all science, yet that science cannot deal with, has no way of approaching; not even to identify its presence or absence; that offers nothing to measure, and nothing to locate, since it has no location.
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A few years ago it occurred to me -- albeit with some shock to my scientific sensibilities -- that my two problems, that of a life‑breeding universe, and that of consciousness that can neither be identified nor located, might be brought together. That would be with the thought that mind, rather than being a late development in the evolution of organisms, had existed always: that this is a life‑breeding universe because the constant presence of mind made it so.
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My other favorite quote from the same speech..
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Now, professors sometimes tell their students foolish things, which the students carefully learn and reproduce on exams and eventually teach the next generation.
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__________________
Guardian of the honey and nuts
Let's assume I'm right, it'll save time.
Last edited by Rockstar; 07-09-23 at 10:04 AM.
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07-08-23, 04:45 PM
I say the brain, and all things existing, are a consequence of one MIND, but individual consciousness defining us as an individual character, personality, self-reflective being, are the result of the alltogether-functioning of the brain. Take the brain's work away and see whats left of "you" - nothing. 
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