Noises from the Darkroom: The Science and Mystery of the Mind

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Evolutionary Beginnings

But let us start at the beginning, with a résumé of the evolutionary history of humankind – a fuller version of which comprises the first part of this book – to orientate you. The twists and turns of our long evolution have bequeathed us a mind that, below the surface, is a curious tangle of abilities and limitations, strengths and weaknesses. It is not an instrument of elegant design, but a ramshackled raft, constructed out of a hodge-podge of materials, each of which happened to float by at a time then they could be used. If we could put the human mind in dry dock, take it to bits, and start again from scratch, we would never come up with the Heath Robinson contraption that has been handed down to us.

The vast majority of this mental raft – and the vast majority of its intelligence – lies below the surface. Conscious awareness arrived, in the course of evolution, probably with the evolution of active hunting as a method of catching food, and probably earlier and more clearly in species that were prey than those that were predators. And it emerged as a corollary of a particular kind of ‘alarm reaction’. But with the development of social living, of language, and of the technology that could make life stable and relatively affluent, consciousness got appropriated by a variety of other systems within the mind, until today it has almost (but not quite) lost its original nature and purpose. In the detailed unravelling of this story, we can find an adequately complicated diagnosis of where and how the mind missed its way.

The mind is a specialized development of the brain, which is a specialized development of the body. The current myth of the body as a mobile pillar of meat piloted by an individual blip of conscious intelligence is false and harmful. Biology is telling us clearly that the body, with all its physical and psychological accoutrements, is a system, an intricate dance of processes and interactions that depends for its existence on continual penetration and perturbation by wider systems of which it is an inextricable part. The body ‘knows’ this; the brain ‘knows’ it’; the mind ‘knows’ it. Only the self-conscious ‘I’, sitting atop this mountain of interdependency, denies and ignores it. When ‘I’ is switched off, the brain-mind immediately recalls what it had affected to forget. ‘Ah yes,’ it whispers to itself; ‘I remember. I belong.’

If the essential mystery at the heart of human experience has somehow been squeezed out of the myths by which we are living, then science – twentieth-century empirical science – can re-mind us of this, just as powerfully as Mozart or meditation. ‘The mind’s new science’, as Harvard psychologist Howard Gardner has dubbed it, is doing just that. It shows us that mysticism is necessary, and mystery is logical.

TWO Body-Building: The Origins of Life (#ulink_08eadcfe-37bd-58e9-b838-72f5846c5366)

Evolution is a change from a no-howish untalkaboutable all-alikeness to a somehowish and in general talkaboutable not-all-alikeness by continuous sticktogetherations and something-elseifications.

William James

We Do Not Compute

The pickle in which humankind currently finds (and loses) itself is due to the mind, and the mind is due to evolution. The conscious human mind cannot be understood just by looking at the way it is now. It is the tip of a vast evolutionary iceberg that has taken millions of years to form. As in all evolution, the later builds on the earlier; it can modify what went before, but it can never replace it. We have become so preoccupied with consciousness that we have forgotten the unconscious bulk below the surface. Minds are merely the software of the intricate biocomputers we call brains. And brains are the central organizing systems, the communications rooms, of high-tech bodily communities that have multiple goals and needs, and which live in environments that afford almost limitless opportunities. And all this is in aid of smart, tenacious, replicating molecules, who have it in their nature to persist and to breed. The abilities to solve crossword puzzles, to bungee-jump, and to have rows with our children are recent curiosities, balanced precariously atop a tower of earlier discoveries and developments.

Already, in this very first paragraph, I have slipped into using the most widely used metaphor for the brain-mind – the computer. And while in the most general sense ‘computing’ is what the brain-mind does, the analogy can be terribly misleading. Computers have no intrinsic goals. The programs that tell the machinery what to do, and what to ‘want’ to do, arise not from an evolutionary source, but from the mind of the programmer. In the case of we human beings, however, the brain and its mind developed over millennia as tools for helping bodies, and the genes that designed them, to survive. Bodies are made of a kind of stuff that needs to keep trading, in a whole variety of different ways, with the world around it, if it is to persist. Computers can be left switched off for years and (all being well) will leap into action again, as if no time had passed at all, when they are next turned on.

Human beings and other animals grow and evolve. Computers get redesigned, sometimes from scratch. People need to eat to live. No computer has yet been discovered taking a bite out of its desk. There has been a film called The Cars that Ate Paris, but not yet one called The Laptops that Ate IBM. You can understand everything important about a computer by looking at it ‘now’. You can understand very little about the human mind without investigating how it came to be. Computers can be built out of a variety of different materials, and they may end up doing very similar kinds of things. The operation of brains and minds is entirely dependent on the stuff of which they are made, and the worlds they and their ancestors grew up in.

Yet the conscious mind’s view of itself downplays its evolutionary history, and its unconscious substratum, shamelessly. Part of the problem with the human brain-mind is that it has come to see itself as a kind of computer – without embodiment, without any history other than its own experience, without ecology. It has even come to identify only with what comes up on the screen of consciousness, and to ignore its own circuit boards and microchips. To straighten the mind out, it is necessary to remind it of its relationship to its brain, its body, its world and its ‘unconscious’. That is where we have to start.

A Brief History of Slime

Let us briefly go back right to the beginning of life: to the primaeval ooze. A very long time ago – 4 billion years or so – there was no life; only an atmosphere containing simple molecules such as methane, ammonia, carbon dioxide, nitrogen and water vapour. There was no free oxygen, no ozone layer between the Earth and the sun, so powerful ultraviolet rays could enter the atmosphere unfiltered. Since Stanley Lloyd Miller’s classic experiment in the early 1950s, it has been known that some at least of the basic molecular building blocks of life – the amino acids – can be produced by subjecting mixtures of these gases to the levels of ultraviolet radiation and the types of electrical discharge that would have been around in those early days. Simple chemical processes would have enriched the prehistoric broth to the point where it contained several of the necessary chemical ingredients of life.

It is a long way, though, from simple proteins and sugars to the molecules and structures that are characteristic of all living systems, from amoebas to Buddhas. There are 200 or so of these essential ‘molecules of life’, and they collaborate with each other in such intricate and self-supporting ways that the whole structure of relationships on which life depends seems to hang together like a multidimensional archway – remove one piece and the whole thing collapses. And while some of them can be found in different brands of primordial soup, many of them, in order to be synthesized, seem to need exactly the kind of environment provided by the living cellwhose origins we are eventually trying to account for. We are faced with a classic ‘Chicken and Egg’ situation: in order to explain how cells were made, we seem to need to postulate the existence of cells!

There are a number of ingenious theories about how the bridge between simple molecules, and life, was built. Graham Cairns-Smith of the University of Glasgow has suggested that, just as an archway needs a temporary support while it is under construction, which can then be taken away when the arch is finished, so the first molecules of life were able to be synthesized and concentrated within the tiny cell-like cavities that are present in certain types of clay. Once these carbon-based molecules had formed their mutually supportive society, they were then able to kiss the clay goodbye.

However it happened, there emerged, amongst these molecules of life, the ones that were to serve as the powerhouse for the whole of evolution: the self-replicating molecule known as DNA. Each DNA molecule is like a long message, an instruction manual for making all the different constituents of living matter, written in an alphabet comprising only four letters. A simple bacterium needs a manual equivalent to about 1000 book pages to make it and keep it going. The ‘library’ needed to construct and run a human being, contained within the 46 chromosomes of every cell in the body, is equivalent to about a million pages. And, of course, each of these chromosomes is able to photocopy itself with incredible accuracy and elegance, whenever its parent cell divides.

Under the conditions that might have been expected 3,500 million years ago, amino acids have been shown to form into primitive celllike structures. By 3,000 million years ago, cells had developed which were able to generate energy from light: they were capable of photosynthesis. As this process consumes carbon dioxide, and liberates oxygen gas, the composition of the atmosphere was slowly but radically changed. The development of the ozone layer meant further reductions in the amount of ultraviolet radiation penetrating through to the Earth’s surface, and increasingly hard times for the original bacterial or prokaryotic cells. In order to take advantage of the changing conditions, much more complex kinds of cells developedthe eukaryotic cells, from which all multicellular species are derived. These basic building blocks of animal tissue are themselves comprised of collections of different kinds of simpler prokaryotes.

Each of our human cells, for example, contains mitochondria, which were originally completely independent little creatures. They still have their own DNA which is quite different from that contained within the nucleus of their adopted parent cells, yet have chosen to settle down and work as the energy factories of the cell in return for board, lodging and protection.

The first multi-cellular organisms began to appear on the Earth about 700 million years ago. The basic design of the animal body has over millions of years ramified into the galaxy of different species of which television nature programmes constantly remind us. But the fundamental specification has remained surprisingly constant. Just as city society has evolved in strikingly similar ways all over the world, so the body has come to delegate its necessary functions to a familiar repertoire of subsystems. Like a colony of ants, but more compact and sticky, cells cling together, throwing their lot in with each other, and contributing their specialized talents to the overall good of society, in the hope that ‘All for One and One for All’ will turn out to be a successful strategy.

For example, all bodies develop subsystems whose job it is to turn food into a usable form, transport it round the far-flung part of the empire, and deal with waste disposal. Some citizens roll themselves into a tube, the walls of which learn to weep lubricants that soften the food and start the process of converting raw antelope or sunflower seeds into a usable nutritious juice. To make use of a greater variety of raw materials, some of them quite tough, other brave citizens build themselves into hard white rocks at the entrance to the tunnel, and crush the ore that passes between them. Constant supplies of fresh water are needed by the food processors, and the development of a flappy pink proboscis helps to flip moisture into the front end of the tunnel. While at the other end, sewage operatives divide the waste products into liquids and solids, and develop short-term holding capacities, so that the garbage can be dumped when it is safe, and smart, to do so. If you are evolving into a fish, it does not matter too much if you leak as you go; but if you are on your way to becoming a bird, you are at an evolutionary advantage if you can learn the trick of not fouling the nest.

To work properly cells, like cars, need not only suitable liquid fuel but air, so another subsystem evolves to extract the vital ingredients of air and deliver them. The body grows an internal complex of beaches, a vast coastline along which the air can continually lap, and where chemicals can trap the precious oxygen. In order to maximize the vigour and intimacy of this contact, the enfolded coastline develops into an internally-regulated bellows that constantly exchanges used air with fresh. While inside the body there develops an intricate network of canals that make Venice look like the Sahara desert, again with a central pumping station that keeps the currents flowing, and ensures that supplies reach every nook and cranny.

Ingestion is a crude process, and sometimes things get sucked in at the front end of the tube that interfere with or threaten the smooth workings of the community. Gradually some residents are delegated to lookout duty, their task to discover, through evolutionary trial and error, how to predict by sight or smell or taste what is wholesome and what it is better to avoid or spit out. But mistakes are still made, and so other members of the commune are bred for fighting, forming a territorial army that constantly patrols the system, riding shotgun on the precious supplies, detecting and overpowering intruders and dissidents before they can throw a spanner in the works. And this immune system has to develop the ability to tell, with great accuracy, friend from foe, so that it does not inadvertently submit innocent but unrecognized members of its own family to ‘friendly fire’. Chilean neuroscientist Francisco Varela has shown that these internal defenders of the community must possess, like the Freemasons, an increasingly sophisticated repertoire of secret handshakes which will unmask the imposters – increasing because the ranks of the potential invaders are always changing, and their powers of penetration and impersonation are always growing.

Unless the whole body is fortunate enough to find itself rooted in the Promised Land, where abundant supplies of milk and honey naturally and continually drift into the open end of its tube, it may well discover the advantages of arms and legs. With arms (and especially with hands on the ends of them) that are hooked up to your lookouts, you are able to reach out and grab passing morsels that would not otherwise have fallen into the top of your tube. (A long sticky tongue that you can aim and flick does the same trick.) Legs expand your hunting ground even further, as well as enabling you to take some evasive action when you find that you have unwittingly strayed into someone else’s. Both attack and escape are hit and miss affairs, of course, and it will have taken hundreds of generations, and many of its great uncles starved or eaten, to get to the point where any animal is as skilled as it is. And each species is of course never a finished product, but just one snap-shot of the continually unfolding evolutionary drama.

What is Evolution?

It will be obvious that I am assuming the general validity of an enlightened neo-Darwinian view of evolution. There may have been a few amino acids or simple proteins that arrived on the earth via meteorites, and these may even have helped to kick-start the evolution of self-replicating molecules. But within a scientific context we are not yet obliged to take seriously such imaginative fancies as the arrival of fully-fledged life-forms from other planets, or the guiding hand of a Cosmic Architect in whose eyes humanity is the highest pinnacle of Creation. To a shark, a beaver, a cockroach or a bacterium, it must also look as if they are the target towards which evolution has been unerringly aimed, and the species for whom the world has been designed.

The increasing complexity of the living world is real enough, but any ‘intention’, any overall ‘design’ or ‘purpose’, can only be conceived, and projected backwards into history, with the benefit of hindsight. We can say, in general, that it is in the nature of a world that contains self-replicating entities subject to the developmental constraints of natural selection, that things are going to diversify, become more intricate, colonize more inhospitable habitats, and develop greater flexibility in the face of environmental change; but how that is going to pan out would be in (if there were any) the laps of the Gods. As Graham Cairns-Smith puts it: ‘What does happen in evolution depends so much on particular circumstances that the course of evolution over the long term is about as predictable as the meandering form of a river or the exact shape of tomorrow’s clouds: one can only illustrate possibilities and indicate general expectations.’

The course of true love between species and habitat never runs smooth for very long, however, because the incumbents themselves are changing the environment – using up resources, creating waste, building nests or commuter towns. And other tribes or other species are learning new tricks that will keep you on your evolutionary toes. Gradual changes of cooling or warming are happening on a local or a planetary scale. Huge lumps of flying rock – meteorites, or more likely, comet showers – occasionally land in your back garden. And so on. As Cairns-Smith goes on to say: ‘Any theory that is to explain the variety and complexity of living things must also take into account the varied and varying challenges sat up by a varied and varying environment. Nature, as breeder and show judge, is continually changing her mind about which types should be awarded first prize.’

Another vital constraint on evolution is its inability to subtract. It is never possible for evolution to reconsider an earlier ‘decision’ in the light of subsequent experience. Each step can only modify the existing gene-pool; it can never rub it out and start again. A favourite example of Stephen Jay Gould’s is the giant panda, a beast that is evolved from carnivorous stock, yet now has a vegetarian lifestyle. The carnivore’s paw comprises five equivalent fingers or toes, and has no ‘thumb’, as the primates do, which can move independently of the fingers to provide a powerful grasp or a precise grip. Yet this is just what the panda now needs; its diet requires it constantly to strip the leaves from young bamboo shoots – a job for which an opposable thumb would have been ideal. Trapped by its pre-set evolutionary trajectory, the best the panda can do is develop a clumsy pseudo-thumb out of one of its fingers. As Gould says: ‘If God had started from scratch to construct a panda to eat bamboo he would have built it differently…The world is full of these imperfections, and they record the path of history’.

Just as the path of evolution is littered with these awkwardnesses, so is it full of serendipity. Structures, faculties and behaviours arise as an ‘answer’ to a local ‘question’, and then may turn out to have more potential than met the original eye – or, to take a different sense, the tongue. This may have originally evolved as part of the drinking mechanism, as a device for moving food around in the mouth, as the prime site of the taste buds, or as part of the apparatus for making sure that the intake of food and air do not get muddled up. It probably did not originally develop as part of the Fur Insulation System of the ancestors of the cat family. Yet, once in existence, it came, opportunistically, to play an important role in keeping the fur clean. Dirty, matted fur insulated much less well, and the job of keeping it clean may well have stimulated the tongue to become rougher, in order to make a better brush. But such a development would have only have been ‘allowed’ to the extent that it enabled the tongue to continue to play its role as part of the Food Processing System.

Other species have capitalized on the tongue in different ways. Dogs use it to help reduce body heat by panting, while human beings, in certain cultures, use it for exactly the reverse purpose – as an essential component of the Sexual Arousal System. Not to mention the fact that without it we would all be speaking in sign language, and there would be no singing. As I shall argue later, we can only understand the evolution of consciousness if we look at it in the same way. What it is and what it does now have to preserve the function for which it was first evolved. But there have been so many twists and turns to the evolutionary tale since then that this original function has become quite obscured by later developments.

Contrary to popular belief, natural selection does not pit every individual against each other in a ‘Nature red in tooth and claw’ kind of way. If cooperation helps individuals to stay alive long enough to breed, and to increase the chances of their genes, through their offspring, surviving, well and good. Neo-Darwinism is quite at home with the principle of enlightened self-interest; in fact co-operation and collaboration both within and between species are turning out to be the rule rather than the exception. Sophisticated flowers make nectar for the bees, but they also make sure that their visitors leave with a good blob of pollen on their backsides. Big fish allow little fish to clear up their leftovers (without the tiddlers fearing that they themselves are on the menu) provided they floss their host’s teeth while they are about it.

The balance between ‘selfish’ and ‘altruistic’ behaviour emerges as a pragmatic issue of genetic survival long before it surfaces as a moral question or a cultural concern. Indeed there may still be within human beings a biological morality which we have, in our enchantment with consciousness and spoken language, forgotten; which our explicit ethical codes are a poor substitute for; and which it might be possible, if we were to relocate our personal centres of gravity, to re-experience. At the very least the neo-Darwinian theory of evolution advises us to keep this an open question.