Chatto+Windus 1992

S. 15

Keywords: a history of mental evolution - I take it for granted that the human mind does indeed have an evolutionary history, extending through nonhuman prototypes- monkeys, reptiles, worms - all the way back to the first glimmerings of life on Earth. - PHENOMENON - an event as it appears to an observer - subjective feelings - sensitivity - action patterns - What is happening to me - what is happening out there - While one path led to the qualia of subjective feelings and first-person knowledge of the self, the other led to the intentional objects of cognition and of objective knowledgege of the external physical world. -

...the way to catch consciousness will be to tickle it....

There are several ways to catch a fish (if not a monster). You can drag a net across the river, and pull in everything there is: but this way you get the weeds, the frogs and old boots too. You can put a worm on a hook, and cast it into a likely-looking pool: but this way you risk choosing the wrong pool or a day when the fish are just not feeding. Or (so an old Scotsman told me) you can tickle it: you walk stealthily along the river-bank until you see your fish hanging in the water just upstream; you lean down from the bank and lower your fingers ever so slowly under the fish’s belly; you stroke it; and then (so he said) the fish just lets you lift it out. I believe the way to catch consciousness will be to tickle it. That is to say we should discover where it is lying, approach it slowly, and then charm it into our hands. The story-line of the book will be a history of mental evolution.

By ‘history’ I mean evolutionary history, and evolutionary history on a grand scale: from the creation of the earth to the emergence of modern human beings. And the reasons for embracing such a vast time-scale are twofold: first, so as to make no preliminary assumptions about when mind and consciousness emerged, and second, so as to make no assumptions about objective physical reality.

Suppose we were to take a relatively shorter time span, say only the last million years. We should then be faced with two existing sets of facts: on the one hand the existing phenomena of subjective experience and on the other the existing phenomena of the material world. The problem then might be precisely the problem we met in the earlier chapter, namely that those two classes of phenomena seem simply not to join.

When we take the longer view, however, we may be able, as it were, to get in on the ground floor before these existing phenomena were phenomena at all.

Perhaps we may discover that both classes of phenomena, rather than being ‘given’, are themselves historical creations: the left hand of subjective experience and the right hand of the material world being outgrowths from a common source. In that case the problem will be to trace their separate paths of evolution.

I take it for granted that the human mind does indeed have an evolutionary history, extending through nonhuman prototypes- monkeys, reptiles, worms - all the way back to the first glimmerings of life on Earth. (If, to the contrary, human beings have been the product of all-at-once divine creation, my line of argument would fail; but so would natural philosophy in general.)

Before life emerged, let’s say four thousand million years ago, when the planet Earth was formed, there were presumably no minds of any kind at all.

PHENOMENON - an event as it appears to an observer.

It follows that four thousand million years ago the world was totally unexperienced and unknown. Nothing within it had ever been seen, heard, touched, smelled, thought about, represented or described. And hence nothing within it, at that time, existed as a phenomenon for anyone. I am, I should say, using the term ‘phenomenon’ here in the old-fashioned way: a ‘phenomenon’ (from the Greek phainein, to appear) is an event as it appears to an observer, as distinguished from what it might consist of in itself.

Then, at that stage of our planet’s history, the phenomena we now call subjective feelings were not yet in existence: no sensations of red stabs of pain. Less obviously, although no less true, the phenomena we now call the phenomena of the material world were not yet in existence: no red light or sharp objects, or even objects weighing five grammes or seven metres high - at least nnothing that had ever been thought of in that way. I am not m g a particularly deep point here: just the point that before anything could exist as a subjective feeling or as a physical event, th had to be someone around to whom that was what it was or meant.

REPRESENTATION: You may object that you cannot imagine a time when nothing existed in any phenomenal form. Were there not volcanoes, and dust-storms and starlight long before there was any life on Earth? Did not the sun rise in the East and set in the West? Did not water flow downhill, and light travel faster than sound? The answer is that if you had been there, that is indeed the way the phenomena would have appeared to you. But you were not there: no one was.

And because no one was there, there was not - at this mindless age of history - anything that counted as a volcano, or a dust- storm and so on. I am not suggesting that the world had no substance to it whatsoever. We might say, perhaps, that it consisted of ‘worldstuff’. But the properties of this worldstuff had yet to be represented by a mind.

Now, four thousand million years later, the situation has dramatically changed. Today there are literally billions of animals with minds inhabiting the planet, and the world has become very widely experienced and very widely known. In particular the phenomena both of subjective feelings and of the material world have come into existence as such for us. Today we can go beyond our given interactions and conceive of the existence of comparable phenomena in parts of space where we have never been, and far back in the past and forward in the future. We can imagine the sound of a tree falling in the forest when there is nobody around. We can even imagine, perhaps, the original Big Bang. The fact remains that, whatever the Big Bang was like, there was no phenomenal bang at the time that it occurred. Having fixed both ends, the big question must be what happened in the period in beween.


I shall merely sketch here a possible version of the history, in several Acts. (And although, given what I have just said, there must be something paradoxical in using modern concepts to discuss the distant past, this will have to be a contemporary mind’s-eye view.) If I seem to move unreasonably quickly past episodes, perhaps whole scenes, that deserve more careful and detailed treatment. I can only ask you to take some of it temporarily on trust.


In the primeval soup, chance brought together the first molecules of life, with the capacity to generate new copies of themselves. Time passed and Darwinian evolution got to work, selecting - and hence helping to design - packets of worldstuff with ever greater potential for maintaining their own integrity and rcproducing. First there were just complex living molecules (like DNA), then single cells (like bacteria or amoebae), then multi-celled organisms (like worms, or fish or us).

Living animals had their own form and their own substance. Not only was each individual animal a spatially bounded package, but in an important sense the contents of the package belonged together. Although the meaning of ‘ownership’ and ‘belonging’ is intuitively obvious (which tells us how important the idea of ‘owning’ our own bodies remains to our own lives), they are elusive concepts. For the moment all I want to imply is that, whether at the level of an amoeba or an elephant, the animal was a self-integrating and self-individuating whole. And unlike other bounded objects - such as a raindrop or a pebble or the moon - its boundaries were self- imposed and actively maintained. On one side of its boundary- wall lay ‘me’, on the other ‘not-me’: and it was ‘my life’, ‘my form’, ‘my substance’ that was at risk.

So boundaries - and the physical structures that constituted them, membranes, skins - were crucial. First, they held the animal’s substance in, and the rest of the world out. Second, by virtue of being located at the animal’s surface they formed a frontier: the frontier at which the outside world impacted the animal, and across which exchanges of matter and energy and information could take place. Light fell on the animal, objects bumped into it, pressure waves pressed against it, chemicals stuck to it...Some of these events were generally speaking, ‘a good thing’ for the animal, others were neutral, others were bad. Any animal that had the means to sort the good from the bad - approaching or letting in the good avoiding or blocking the bad - would clearly have been at a biological advantage. Natural selection was therefore likely to select for ‘sensitivity’.


Being sensitive need have meant, to begin with, nothing more complicated than being locally reactive: in other words, responding selectively at the place where the surface stimulus occurred. Just as today we might say that a person is sensitive to sunlight if he responds to sunlight on his neck with local reddening, so the first types of sensitivity would have involved, for example, local retraction or swelling or engulfing by the skin.

Soon enough, however, more sophisticated types of sensitivity evolved. Sense organs became more discriminatory between different kinds of stimuli, and the range of possible responses increased.

Instead of or as well as a stimulus inducing a local reaction, information from one part of the skin got relayed to other parts and caused reactions there. And by the introduction of delays in transmission and the combination of facilitation and inhibition, the way was open for the animal’s responses to become better adapted to its needs: for example by swimming away, rather than just recoiling from a noxious stimulus.

In time, different stimuli came to elicit very different action patterns. We might imagine, to take a hypothetical example, that an animal living in a pond swam upwards in response to red light, and downwards in response to blue light (thus tending to go deeper in the middle of the day). Since information about the particular stimulus was now being preserved and carried through into the particular action pattern, the action pattern had come to represent - at least to replicate symbolically - the stimulus.

With this level of sensitivity / reactivity, however, it could hardly be said that environmental events had acquired much ‘meaning’ for the animal Still, even by this stage something about the status of the world was changing. Certain events were being responded to as good and bad, as edible or inedible, as of significance to ‘me’. And the reason for emphasising the as here is to emphasise the essential difference between, on the one hand, something’s just being good or bad, and, on the other, the animal for whom it is good or bad reacting to it as such. Compare, for example, the effects of low humidity on two bounded objects: a woodlouse and a puddle. The heat is ‘bad’ for both of them because it dries them up. But whereas the puddle just sits there and shrinks in size, the woodlouse runs away. Both react to low humidity: but while the puddle’s response is non-adaptive and carries no implication of eing meaningful, the woodlouse’s response potentially does: it implies ‘here is a situation not much to my liking’. ‘Liking’ is another of those concepts that I shall want to explore more detail later on. The question of how much an animal likes being stimulated is, I think, basic to the question of what it is like the animal to respond to the stimulus (and the pun on ‘like’ is thus not accidental). There are many dimensions and degrees of liking and disliking, corresponding to the many different kinds of sitivity and responsivity that have evolved. Within this rich space of affective reactions there must have bcen wide scope for the evolution of ways of experiencing the world that varied in subjective quality.

To begin with, sensitivity and responsivity were intimately linked. And so in some ways they always have been and still are. Consider, for example, that an itch is something you want to scratch, or that a heavy object is something it is difficult for you lift.) But as animals became increasingly sophisticated at attuning their behaviour to the environmental situation, the sensory side and the response side of the process must have become partially coupled. Before long a central site evolved, where representations - in the form of action patterns - were held in abeyance before they were put into effect.

Thus action patterns had become action plans, and representations had become relatively abstract.The place where they were held in store could be said to be the place where they were held in mind. Mind, more than any other term, is embarrassingly difficult to give a simple definition. But, recognising fully the circularity, I shall let the term ‘mind’ connote for the moment just the representive faculty I have here referred to. In short, animals first had ‘minds’ when they first became capable of storing - and possibly recalling, and reworking - action-based representations of the effects of environmental stimulation on their own bodies.

The material substrate of the mind was nervous tissue, which in higher organinsms became centred in a ganglion or brain; and it is to be remarked that even in animals like human beings the neural tube which forms the brain during embryological development derives from infolding of the skin.

By the time prototypical minds had evolved, it could be said that some events in the world had taken on the status of meaningful phenomena. For the first time in history - the first time in fact since the universe began - certain events, namely those occurring at the surfaces of living organisms, had begun to exist as something for someone. If you will pardon the word-play, these events had begun at last to be ‘matters of fact’ because someone ‘minded’ about the fact they ‘mattered’ to his bodily well-being.

So the phenomenology of sensory experiences came first. Before there were any other kinds of phenomena there werc ‘raw sensations’ - tastes, smells, tickles, pains, sensations of warmth, of light, of sound and so on. It could have happened, I suppose, that this was where mental represenation stopped evolving. Indeed it is quite conceivable that somewhere far away in another galaxy where life is evolving on another planet, this is still as far as it has gone; even on Earth it may be as far as some primitive animals have got to; it may even correspond to the condition, for a short time, of a newborn human baby. But it is clearly not where our own mental representation rested. For if it were, we would still be living in a world where objective physical phenomena were quite unknown.

From early on there was, however, another track to mental evolution. On the one hand, as we have seen, animals benefited from having an ability to assess their own current state of being to answer questions about ‘what is happening to me’ - ‘What is it like to have red light arriving at my skin?’

But on the other hand they would certainly have benefited further if they had had an ability to assess the state of the external world: to answer questions about ‘what is happening out there’ - for example, ‘Where is the red light coming from?’

What is happening to me - what is happening out there

But the questions ‘What is happening to me?’ and ‘What is happening out there?’ were always different kinds of questions, which must always have required very different kinds of answers. Consider a patch of sunlight falling on thc skin of an amoeba-like animal. The light has immediate implications for the animal’s own state of bodily health, and for that reason it gets represented as a subjective sensation. But the light also signifies - as we now know - an objective physical fact, namely the existence of the sun. And, although the existence of the sun might not matter much to an amoeba, there are other animals and other areas of the physical world where the ability to take account of what exists ‘out there beyond my body’ could be of paramount survival value. Consider a shadow crossing the skin of the amoeba. Here an ability to represent the objective fact of an approaching predator would - if only it were achievable by an amoeba - clearly be of considerably more consequence to the animal’s survival than the ability to represent the body surface stimulus as such.


But how to do it? How to interpret a stimulus as a ‘sign’ of representation of the signified? By the end of the first stage of evolution sense organs existed with connections to a central processor, and most of the requisite information about potential signs was being received as ‘input’. But the subsequent processing of this information, leading to subjective sensory states, had to do with quality rather than quantity , the transient present rather than permanent identity, me-ness rather than otherness.


In order that the same information could now be used to represent the outside world, a whole new style of processing had to evolve, with an emphasis less on the subjective present and more on object permanence, less on immediate responsiveness and more on future possi-bilities, less on what it is like for me and more on how what ‘it’ signifies fits into the larger picture of a stable external world.

To cut a long story short, there developed in consequence two distinct kinds of mental representation, involving very different styles of information processing.



While one path led to the qualia of subjective feelings and first-person knowledge of the self, the other led to the intentional objects of cognition and of objective knowledgege of the external physical world.

When the Earth was formed neither kind of phenomenon existed for anyone at all. Now both exist as such for us. And it is the evolution of these dual modes of representation which goes a long way to explain why now, today, we have this apparent stand-off between two classes of phenomena:

subjective feelings ranged against the phenomena of the material world, quality against quantity, wine against water. As Picasso said (in a rather different context), ‘Nature and art being two different things cannot be the same thing’; and, by the same token, subjective feelings and physical phenomena, being two different sorts of representation, cannot be the same sort of representation.

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