We have three sets of cones (or colour sensors) in our retinas, each of which is sensitive to a different part of the colour spectrum; the brain then constructs the rest of the spectrum by extrapolating from the relative strength of these three. In the case of purple, which occurs when the red and blue sensors but not the green ones are triggered, the brain creates a colour to fill the gap. If your brain were more objective, rather than showing you purple, it would display a patch of flickering grey with the words “system error” on it. — Rory Sutherland in Alchemy: The Surprising Power of Ideas That Don’t Make Sense (2019), section 6.2
“Consciousness is a fascinating but elusive phenomenon; it is impossible to specify what it is, what it does, or why it evolved. Nothing worth reading has been written on it.” — Stuart Sutherland (1927-98), in The International Dictionary of Psychology (1995), entry on “Consciousness”
Reading about Searle’s Chinese Room Argument at the Stanford Encyclopedia of Philosophy, I came across “Leibniz’s Mill” for the first time. At least, I think it was the first time:
It must be confessed, however, that perception, and that which depends upon it, are inexplicable by mechanical causes, that is to say, by figures and motions. Supposing that there were a machine whose structure produced thought, sensation, and perception, we could conceive of it as increased in size with the same proportions until one was able to enter into its interior, as he would into a mill. Now, on going into it he would find only pieces working upon one another, but never would he find anything to explain perception. It is accordingly in the simple substance, and not in the compound nor in a machine that the perception is to be sought. Furthermore, there is nothing besides perceptions and their changes to be found in the simple substance. And it is in these alone that all the internal activities of the simple substance can consist. (Monadology, 1714, section #17)
Andererseits muß man gestehen, daß die Vorstellungen, und Alles, was von ihnen abhängt, aus mechanischen Gründen, dergleichen körperliche Gestalten und Bewegungen sind, unmöglich erklärt werden können. Man stelle sich eine Maschine vor, deren Structur so eingerichtet sei, daß sie zu denken, zu fühlen und überhaupt vorzustellen vermöge und lasse sie unter Beibehaltung derselben Verhältnisse so anwachsen, daß man hinein, wie in das Gebäude einer Mühle eintreten kann. Dies vorausgesetzt, wird man bei Besichtigung des Innern nichts Anderes finden, als etliche Triebwerke, deren eins das andere bewegt, aber gar nichts, was hinreichen würde, den Grund irgend einer Vorstellung abzugeben. Die letztere gehört ausschließlich der einfachen Substanz an, nicht der zusammengesetzten, und dort, nicht hier, muß man sie suchen. Auch sind Vorstellungen und ihre Veränderungen zugleich das Einzige, was man in der einfachen Substanz antrifft. (Monadologie, 1714)
We can see that Leibniz’s argument applies to mechanism in general, not simply to the machines he could conceive in his own day. He’s claiming that consciousness isn’t corporeal. It can’t generated by interacting parts or particles. And intuitively, he seems to be right. How could a machine or mechanism, however complicated, be conscious? Intuition would say that it couldn’t. But is intuition correct? If we examine the brain, we see that consciousness begins with mechanism. Vision and the other senses are certainly electro-chemical processes in the beginning. Perhaps in the end too.
Some puzzles arise if we assume otherwise. If consciousness isn’t mechanistic, how does it interact with mechanism? If it’s immaterial, how does it interact with matter? But those questions go back much further, to Greek atomists like Democritus (c. 460-370 BC):
Δοκεῖ δὲ αὐτῶι τάδε· ἀρχὰς εἶναι τῶν ὅλων ἀτόμους καὶ κενόν, τὰ δ’ἀλλα πάντα νενομίσθαι.
He taught that the first principles of the universe are atoms and void; everything else is merely thought to exist.
Νόμωι (γάρ φησι) γλυκὺ καὶ νόμωι πικρόν, νόμωι θερμόν, νόμωι ψυχρόν, νόμωι χροιή, ἐτεῆι δὲ ἄτομα καὶ κενόν.
By convention sweet is sweet, bitter is bitter, hot is hot, cold is cold, color is color; but in truth there are only atoms and the void. (Democritus at Wikiquote)
Patterns of unconscious matter and energy influence consciousness and are perhaps entirely responsible for it. The patterns are tasteless, soundless, colourless, scentless, neither hot nor cold – in effect, units of information pouring through the circuits of reality. But are qualia computational? I think they are. I don’t think it’s possible to escape matter or mechanism and I certainly don’t think it’s possible to escape mathematics. But someone who thinks it’s possible to escape at least the first two is the Catholic philosopher Edward Feser. I wish I had come across his work a long time ago, because he raises some very interesting questions in a lucid way and confirms the doubts I’ve had for a long time about Richard Dawkins and other new atheists. His essay “Schrödinger, Democritus, and the paradox of materialism” (2009) is a good place to start.
When we are conscious of being conscious, what are we consciousness-conscious with? If consciousness is a process in the brain, the process has become aware of itself, but how does it do so? And what purpose does consciousness-of-consciousness serve? Is it an artefact or an instrument? Is it an illusion? A sight or sound or smell is consciousness of a thing-in-itself, but that doesn’t apply here. We aren’t conscious of the thing-in-itself: the brain and its electro-chemistry. We’re conscious of the glitter on the swinging sword, but not the sword or the swing.
We can also be conscious of being conscious of being conscious, but beyond that my head begins to spin. Which brings me to an interesting reminder of how long the puzzle of consciousness has existed in its present form: how do we get from matter to mind? As far as I can see, science understands the material substrate of consciousness – the brain – in greater and greater detail, but is utterly unable to explain how objective matter becomes subjective consciousness. We have not moved an inch towards understanding how quanta become qualia since this was published in 1871:
Were our minds and senses so expanded, strengthened, and illuminated, as to enable us to see and feel the very molecules of the brain; were we capable of following all their motions, all their groupings, all their electric discharges, if such there be; and were we intimately acquainted with the corresponding states of thought and feeling, we should be as far as ever from the solution of the problem, “How are these physical processes connected with the facts of consciousness?” The chasm between the two classes of phenomena would still remain intellectually impassable.
Let the consciousness of love, for example, be associated with a right-handed spiral motion of the molecules of the brain, and the consciousness of hate with a left-handed spiral motion. We should then know, when we love, that the motion is in one direction, and, when we hate, that the motion is in the other; but the “Why?” would remain as unanswerable as before. — John Tyndall, Fragments of Science (1871), viâ Rational Buddhism.
A simple book with some complex illusions. It’s aimed at children but scientists have spent decades understanding how certain arrangements of colour and line fool the eye so powerfully. I particularly like the black-and-white tiger set below a patch of blue on page 60. Stare at the blue “for 15 seconds”, then look quickly at a tiny cross set between the tiger’s eyes and the killer turns colour.
So what’s not there appears to be there, just as, elsewhere, what’s there appears not to be. Straight lines seem curved; large figures seem small; the same colour seems light on the right, dark on the left. There are also some impossible figures, as made famous by M.C. Escher and now studied seriously by geometricians, but the only true art here is a “Face of Fruits” by Arcimboldo. The rest is artful, not art, but it’s interesting to think what Escher might have made of some of the ideas here. Mind is mechanism; mechanism can be fooled. Optical illusions are the most compelling examples, because vision is the most powerful of our senses, but the lesson you learn here is applicable everywhere. This book fools you for fun; others try to fool you for profit. Caveat spectator.
Challenger chopped and changed. That is to say, in one important respect, Arthur Conan Doyle’s character Professor Challenger lacked continuity. His philosophical views weren’t consistent. At one time he espoused materialism, at another he opposed it. He espoused it in “The Land of Mist” (1927):
“Don’t tell me, Daddy, that you with all your complex brain and wonderful self are a thing with no more life hereafter than a broken clock!”
“Four buckets of water and a bagful of salts,” said Challenger as he smilingly detached his daughter’s grip. “That’s your daddy, my lass, and you may as well reconcile your mind to it.”
But earlier, in “The Poison Belt” (1913), he had opposed it:
“No, Summerlee, I will have none of your materialism, for I, at least, am too great a thing to end in mere physical constituents, a packet of salts and three bucketfuls of water. Here ― here” ― and he beat his great head with his huge, hairy fist ― “there is something which uses matter, but is not of it ― something which might destroy death, but which death can never destroy.”
That story was published just over a century ago, but Challenger’s boast has not been vindicated in the meantime. So far as science can see, matter rules mind, not vice versa. Conan Doyle thought the same as the earlier Challenger, but Conan Doyle’s rich and teeming brain seems to have ended in “mere physical constituents”. To all appearances, when the organization of his brain broke down, so did his consciousness. And that concluded the cycle described by A.E. Housman in “Poem XXXII” of A Shropshire Lad (1896):
From far, from eve and morning
And yon twelve-winded sky,
The stuff of life to knit me
Blew hither: here am I.
Now – for a breath I tarry
Nor yet disperse apart –
Take my hand quick and tell me,
What have you in your heart.
Speak now, and I will answer;
How shall I help you, say;
Ere to the wind’s twelve quarters
I take my endless way. (ASL, XXXII)
Continue reading This Mortal Doyle…
“Electricity in the Human Body” is the subtitle of this book. Make that the goat, frog, eel, shark, torpedo-ray, snake, platypus, spiny anteater, sooty shearwater and fruit-fly body too. And if Venus flytraps, maize and algae have bodies, throw them in next. Frances Ashcroft gives you a bargeload of buzz for your buck, a shedload of shock for your shekel: The Spark of Life describes the use of electricity by many different forms of life. But it discusses death a lot too, from lightning-strikes and electric chairs to heart-attacks and toxicology. Poisons can be a cheap and highly effective way of interfering with the electro-chemistry of the body:
The importance of sodium and potassium channels in generating the nerve impulse is demonstrated by the fact that a vast array of poisons from spiders, shellfish, sea anemones, frogs, snakes, scorpions and many other exotic creatures interact with these channels and thereby modify the function of nerve and muscle. … The tetrodotoxin contained in the liver and other tissues of this fish [the fugu or puffer-fish, Takifugu spp., Lagocephalus spp., etc] is a potent blocker of the sodium channels found in your nerves and skeletal muscles. It causes numbness and tingling of the lips and mouth within as little as thirty minutes … This sensation of “pins and needles” spreads rapidly to the face and neck, moves onto the fingers and toes, and is then followed by gradual paralysis of the skeletal muscles … Ultimately the respiratory muscles are paralysed, which can be fatal. The heart is not affected, as it has a different kind of sodium channel that is far less sensitive to tetrodotoxin. The toxin is also unable to cross the blood-brain barrier so that, rather horrifyingly, although unable to move and near death, the patient remains conscious. (ch. 3, “Acting on Impulse”, pp. 69-70)
In short, fugu-poisoning is the opposite of electrocution: it’s the absence rather than the excess of electricity that kills its victims. Those “channels” are a reminder that electro-chemistry could also be called electro-mechanics: unlike an electricity-filled computer, an electricity-filled body has moving parts – and in more ways than one. Our muscles move because ions move in and out of our cells. This means that a body has to be wet inside, not dry like a computer, but it’s easy to imagine a human brain controlling a robotic body. But would a brain still be conscious if it became metal-and-plastic too? Perhaps a brain has to be both soggy and sparky to be conscious.
The electrical nature of the brain certainly seems important, though that may be a superstitious conclusion. Electricity is a mysterious phenomenon and so is consciousness, so they seem to go together well. Ashcroft writes a lot about the sense-organs and the data they supply to the brain, but like all scientists she cannot explain how those data are turned into conscious experience as the maths-engine of the brain applies its neuro-functions and neuro-algorithms. However, she does suggest ways in which our consciousness might be expanded in future. Humans have colour vision, based on the three types of cone-cells in our eyes:
Most mammals, such as cats and dogs, have only two types of cone photopigment and so see only a limited range of colour … Other animals live in a world entirely without colour. But humans should not be too complacent, for we are far from having the best colour vision in the animal world and lag far behind the mantis shrimp, which enjoys ten or more different visual pigments. Even tropical fish possess four or five types of cones. (ch. 9, “The Doors of Perception”, pg. 199)
Bio-engineering may one day sharpen and extend all our senses, from sight and hearing to touch, taste and smell. It may also give us new senses, like the ability to form sound-pictures like bats and detect infra-red like pit-vipers. And why not X-rays and radio-waves too? It’s an exciting prospect, but in a sense it won’t be anything new: our new senses, like our old ones, will depend on nerve-impulses and the way they’re mashed and mathed in that handful of “electrified clay” known as the brain.
“Electrified clay” is Shelley’s phrase: like his wife Mary, he was fascinated by the early electric experiments of the Italian scientists Luigi Galvani and Alessandro Volta. Mary turned her fascination into a book called Frankenstein (1818) and her invention is part of the scientific history in this book. The story of bio-electricity is still going strong: there are electric mysteries in all kinds of bodies waiting to be solved. Maybe consciousness is one of them. And if science proves unable to crack consciousness, it’s certainly able to expand it. Reading this book is one way to experience the mind-expanding powers of science, but seeing like a mantis shrimp would be good too.
The most mysterious thing in the universe is also the most intimate: consciousness. It’s an inti-mystery, something we experience constantly at first hand and yet cannot describe or explain. We are each a double bubble: a bubble of flesh and a bubble of conscious experience. The second bubble bursts regularly, when we sleep. Sooner or later, the first bubble will burst too, when we die. And that will be it for the second bubble, the bubble of consciousness. Or will it? Can consciousness survive death? Can it exist without a material substrate? Or without a particular kind of material substrate: the soggy, sparky substance of the brain? Can the clean, dry metal of a computer be conscious? Who knows? The double bubble attracts lots of double-u’s: what, where, why, when, (w)how. What is consciousness? What is its relation to matter? Is it king or courtier? Where does it exist? Why does it exist? When? And how?
Continue reading Double Bubble…