A lecturer who takes as his subject the evolution of mind is confronted by two main challenges. He must consider how anything worthy of being called mind could have originated within a world which, we have every reason to believe, originally consisted only of non-living matter obeying strictly the laws of chemistry and physics; and he must face the problem of how mind-like activities, after they had made an initial appearance on the scene, have evolved to their present state. I will argue that two general principles can explain, or can at least throw considerable light on, both how mind originated and how it evolved. The first of these principles is the Darwinian theory of evolution by natural selection, but we shall need to understand that theory in the form in which it has been formulated in the last few years, rather than in the way which has been considered orthodox over the last three or four decades. The second depends on one of the more recent insights into the modes of interaction between things, which is often referred to by the generic title ‘information’, though as we shall see this is not a very happy term.
I shall not at this stage offer any definition of ‘mind’, taking it that we all know, roughly speaking, what we are talking about. Definitions are, in my opinion, not things to start with but things to approach. Possibly by the end of this lecture we may find ourselves in a more favourable position to offer a definition with some substance and value.
Tracing the evolution of life backward in time, by following the fossil record further and further into the past, we find the variety of living things gradually becoming reduced, the more complicated ones dropping out earlier, so that eventually we find evidence only of quite simple creatures; and at some time in the pre-Cambrian even the evidence of bacteria and algae disappears. At earlier times than that the stage on which we now operate seems to have been lifeless, composed only of chemical atoms and molecules, probably in very different concentrations from those we now know. The atmosphere, for instance, contained very little oxygen and a good deal of ammonia, and the sea was much less salt. In what terms is it reasonable to try to give an account of how living things, particularly things exhibiting minds, could have made their appearance?
There is one school of scientific thought which claims that not only do we have to start historically from an age in which nothing was happening except the chemical and physical interactions of atoms and relatively small molecules, but that also we have to accept the laws of physics and chemistry as the sole foundation for any intellectual scheme about the formation of more complicated things. This is the view nowadays usually referred to as reductionism. It argues that nothing can be considered explained until it has been reduced to physics and chemistry. Earlier in this century, this view was more usually referred to as mechanism. At that time there were still people who repudiated it in extremely drastic ways, arguing that living things involved not only physical and chemical entities, but also some sort of ‘life force’ or ‘vital principle’. These ‘vitalists’, however, did not succeed in making it at all clear just what sort of thing they meant by a life force, and in general they had little influence on the development of biology. On the other hand, from about the thirties onwards, there was another group of influential theoretical biologists who maintained that there is indeed something more to living things than mere physics and chemistry. What they suggested adding to these was not any vitalistic life force, but rather various types of complex inter-relationships between the simple physico-chemical entities; and because of these interactions the complexes exhibit properties and behaviours which cannot be shown by the elements when they were not so related. The separate parts of a car can, when assembled into the right relationships, exhibit the new property of locomotion, including such (at first sight, improper) movements as moving up a hill against gravity. It was suggested that, in a comparable way, the properties we see in living things depend on their physico-chemical parts being assembled in the correct relationships. These ‘organicists’ therefore argued that life involves physics and chemistry ‘plus organising relations’ (Needham, Woodger), or ‘plus systems properties’ (Bertallanfy).
This is quite a useful formulation. There is no doubt that to explain the properties of living things we have to add something to the bare notions which suffice to account for the chemical and physical behaviour of atoms. However, I have always felt that the method of approach of both the reductionists and of the organicist anti-reductionists is fundamentally upside down. Our understanding of the world does not start from a firm knowledge of physico-chemical entities, to which we may or may not have to add something in addition. Following A. N. Whitehead, I should argue that any knowledge we may succeed in acquiring about the world starts from something totally different; namely, from occasions of experience. In an ‘occasion of experience’ there is involved both a knower and a known, a subject and an object, and the content of an occasion of experience is undoubtedly influenced by both of these. The knower has a certain apparatus for perception, and also certain pre-existing interests, some of which are innate and expressed even in the very earliest stages of life: he has what Popper has called a ‘prior knowledge’. Meanwhile the known has, of course, its specific characteristics, which colour the content of the occasion of experience in so far as the knower has the perceptive equipment or the interest to discover them. According to this view the physico-chemical concepts, such as mass, force, energy, atom, etc., are not the items with which knowledge starts. Instead they are notions which we have found it useful to derive from certain occasions of experience. The basic physico-chemical notions are in the first place derived from experiences which involve rather simple contents, such as balls rolling down inclined plains, pendulums, and the combination of hydrogen and oxygen to make water, or of sodium and chlorine to make salt, and such like.
According to this view the fundamental basis of scientific knowledge is not in any set of scientific entities, such as atoms, whether Daltonian, Rutherfordian or quantum mechanical. It is in experiments, which are occasions of experience which have been organised and experienced in a systematic way. The fundamental problem is not to build up a complex phenomenon, such as mind, from a previously given set of simpler entities, such as atoms; on the contrary, it is to search downwards from the complex phenomena to simpler entities adequate to explain them. It is, therefore, not quite correct to say that we have to add ‘organising relations’ to the physico-chemical entities in order to explain life. It would be better to say that in explaining simple chemical behaviour, we can leave out certain properties of the elements which only become important in large and perhaps specially ordered arrangements. For instance, the classical laws of organic chemistry, and the classical descriptions of chemical elements and small molecules, do not account for such phenomena as the allosteric changes in overall shape of protein molecules, which contain thousands of atoms. When this allosteric behaviour was discovered, the change in our knowledge is better described, I think, in ‘delving downwards’ terms, by saying we have discovered something we didn't know before about the properties of atoms as they are exhibited in molecular groupings, than by the ‘building up’ statement that the atoms remain the same but we add something new and disconnected to them.
This reference to the importance of the overall shape of complex molecules, must serve as an introduction to another essential point in my argument. Recently, even the ‘builders up’, who accept the physico-chemical entities as a basis of all scientific knowledge, have realised that something more may be involved in them than the properties of mass, energy, etc., attributed to them in classical theory. This further component might be referred to as ‘specificity’ of spatio-temporal configuration. In the last twenty years or so, mathematicians and engineers have attempted to replace the rather undefined term specificity, which had been much used by biologists earlier, with a more precisely defined notion of ‘Information’. Unfortunately, in order to achieve a precise definition capable of being utilised in a mathematical logical system, they have ‘purified’ the notion until it has become almost useless in connections with biology, or indeed in almost all contexts except that of messages; which was the main business of the Bell Telephone laboratories in which the originator of the theory, Claude Shannon, was employed. ‘Information’, as it emerged into the world of mathematics, is a measure of the degree of selection which has been employed in choosing some particular configuration out of a closed universe of possible configurations. It is concerned only with the specificity within a particular universe of possible specificities. For instance, the amount of ‘Information’ contained in the letter A is less if it is chosen out of the English alphabet of 26 characters than if it is chosen out of the Russian alphabet with 29. Moreover, the amount of ‘Information’, in this sense, has nothing whatever to do with bringing about any action outside the closed universe; that is to say, it has nothing to do with ‘meaning’, in any sense of that term. The information content of a message written in English words is just the specificity of the string of letters in which the words are spelt. Consider the two messages:
MEET HIGH MARKET TWELVE TEN
MEAT HIGH MARKET TWELVE TON
The differences in ‘Information’ are simply that the third letter from the beginning is an E in one and an A in the other, and the penultimate letter is E in one and an O in the second. ‘Information’ Theory has nothing whatever to say about the fact that the first is obviously about an appointment to meet at the corner of High Street and Market Street, and the second is a message from a wholesaler that the stocks are going off and had better be got rid of as quickly as possible.
This limitation in the meaning of ‘Information’ made it possible to develop a mathematical theory which is very useful in connection with transmission of messages along channels, but effectively ruined it as a word which is useful to apply in wider contexts. Rather unfortunately, the mathematical theory assigned to the measure of ‘quantity of Information’, a formula which was identical in algebraic form with one of the most famous formulae of thermodynamics, namely that for entropy. This at first led Shannon to identify the amount of information given out by a source with its entropy. Later, Warren Weaver developed an alternative interpretation, that the quantity of information contained in a message is the negative of its entropy. It was Weaver's rather than Shannon's interpretation which became fashionable, and the new word ‘negentropy’ was invented to mean ‘quantity of information or negative entropy’.
The relevance of all this is that there is no doubt that reactions in living systems are very much concerned with the specificity rather than the mass or energy of the components. It is the specific arrangement of nucleotides along the chain of DNA which determines what that gene will do; it is the specific shape in three dimensions of a protein molecule which determines what sort of enzyme activity it will exhibit; and there are many other examples. For a time it became fashionable to discuss this sort of specificity in terms of negentropy, and some of the most penetrating minds, when they turned from physics to biology, were deceived for a time. Thus Schroedinger, in his elegant essay What is Life? in 1944, indulged in aphorisms such as ‘life feeds on negentropy’. However, he soon came to realise that this is an inadequate way of looking at the situation, and he withdrew or at least greatly qualified the remark in the later editions of his book.
The main point is that the specificity with which biology is so deeply concerned is not a static specificity, with no meaning outside itself. It is rather the possibility of bringing about, or tending to bring about, a certain type of activity in appropriate things which react with it. It is, in fact, a specificity of instruction, the imparting of one particular program, or algorithm. We are returning here to a theme which has come up often in these lectures. Christopher, for instance, has been insisting that language is basically to do with programs or instructions, rather than with imparting descriptions from which nothing follows.
Of course the word information, as it is used in ordinary speech, often has some implication that the information will be useful as a guide to action. But it is pretty ambiguous in this context. In fact, during World War II, there was a useful distinction made in the slang of the RAF, which distinguished the ‘Info’, a lot of boring rigmarole about useless facts, from the ‘Gen’, the real stuff you needed to know to tell you how to operate. When we say that biological systems work by means of the programs or instructions incorporated in their components, this is a long-winded way of saying that it's the gen, not the info, that matters for them. It is not negentropy they feed on, but it might have made some sort of sense to call it gentropy, if I may coin an unnecessary word.
It is not only biological systems that feed on gen. There are some physico-chemical systems, which no one would dream of calling living, which very clearly do so too (possibly they all do, but I will not pursue this point here). Consider the minerals making up that, at first sight, boring material, clay. They have been discussed in some detail from this point of view by Cairns Smith in his book The Life Puzzle. Clay minerals consist of crystals in which atoms of silicon, oxygen and a number of metals, such as aluminium, iron and various rarer and less frequent ones, are arranged in a three-dimensional lattice. The lattice is such that at any given time in the growth of the crystal its boundary is a flat two-dimensional plane, with a particular arrangement of these atoms at certain points on it. Now the forces at work are not terribly choosy about which particular atom goes into which place. At one particular point on the surface there might be an atom of aluminium or alternatively there might be an atom of iron, or some other substance. ‘Ha!’, the information theorists will say, ‘this surface can encode a great deal of “information”’. So it can, but the point is that this is not mere info, it is gen. If there is iron instead of aluminium at point X, and the crystal is in a solution which allows it to grow by the deposition of a new layer of atoms on top of the old one, it is much more likely that another iron atom will take this place in the lattice of the next layer. The presence of iron at X is an instruction for building the next layer.
Whatever we imagine the first living systems to have been like, they must have been even more deeply involved in a traffic of instructions. Any type of hereditary material, be it DNA or anything else, which can be transmitted from one ancestral system to two or more daughter systems, must in effect contain instructions for its own copying. Moreover, in all the living things as they are on this earth, the copying system is carried out by mechanisms, such as enzymes, which operate by means of instructions built into them. Finally, systems which we consider worthy candidates to be granted the name living, differ from things like clay minerals in that they contain instructions, not only for copying, but for the elaboration of structures which can actively operate on surrounding materials. These new embodiments are what geneticists speak of as the phenotype. The crucial role of instruction-generated phenotypes as a fundamental aspect of living systems has been a dominant theme in recent discussions of the theory of general biology (see the four volumes entitled Towards a Theoretical Biology, edited Waddington, Edinburgh University Press).
The early stages in the evolution of life therefore involve not only physico-chemical mass, energy, atoms, and so on, but also specific instructions. We find the firmest evidence of mind when we look at the other end of evolution, as in our ‘occasions of experience’, and we are again, of course, fundamentally involved in a traffic of instructions. A knower does not merely sit down before the known, and observe it without comment or response. On the contrary, he brings to it certain predispositions, or interests, and observes certain characteristics more than others. The content he finds in the occasion demands a response. As Popper has put it, the ‘prior knowledge’ with which he comes to the occasion is such that what he receives from it is not mere information but instructions or challenges.
In the light of this discussion, the evolution of mind appears as a transition from the instructional traffic involved in the very simplest living things, or even in the pre-biotic systems such as clays, to the much more complex traffic of instructions involved in our own occasions of experience. We can see two ends of the evolutionary range in similar terms. We have evaded the dilemma of considering the beginning of the evolutionary process as depending on nothing but atoms, forces and physico-chemical factors, while the other end involves something of a totally different character we call mind. One recent author who has advanced a similar view is Stephen Black. In his book The Nature of Life, he also draws attention to the importance of instructional traffic in all the processes of life (unfortunately he has not escaped from the fashionable convention of speaking of information when what he really means is instructions). His next step, however, is to expand the use of the word ‘mind’ to cover the whole range of situations involving instructional traffic from the very simplest to the most complex. This is hardly satisfactory, since, as we have seen, the simplest such situations occur in things like clay minerals, and it is hardly illuminating to speak of them having minds. When God fashioned us out of clay, he may have picked the right material to start from, but there was still a lot to do. What we need to do is to consider the nature of the evolutionary processes which have led from the simpler situations to the more complex ones.
In my second lecture last year, I sketched some of the broader characteristics of evolution. I pointed out that it is a process which occurs not in individuals but in populations of individuals. Any population contains a large variety of different hereditary potentials. Each individual as it grows up will develop some characteristics—making up its phenotype—which depend partly on its hereditary endowment and partly on the particular circumstances it happens to meet during its lifetime. And it is its phenotype which enables it to meet more or less successfully the demands made on it by its way of life, to leave more or fewer offspring, and to contribute more or less to later generations. The demands made on it depend on the way it spends its life. I gave as an example, a horse which can escape from its enemies by running away or by standing and fighting back. Which of these two alternatives it follows is a characteristic of its phenotype, developed gradually as the horse grows up, depending partly on hereditary predispositions and partly on external circumstances, such as other horses whose behaviour it copies, and so on. We describe these alternative forms of behaviour by saying that the horse opts for one or other of a number of goals—either the goal of winning the race by running away, or the goal of beating the predator in a stand-up fight. I argued that any set of behavioural acts in a living creature would only tempt us to ascribe mind to that animal, if they tend to bring about the achievement of some definable goal. If they were a mere higgledy-piggledy collection of responses to any instructions the surroundings happened to throw out, with no central theme or guiding principle, they would seem as mindless as the movements of a feather blowing about hither and thither on a gusty day.
In discussing the evolution of mind, we therefore have to consider first how goals arise. But then I shall want to raise the question whether having only one goal would be an adequate claim to having a mind.
As to the origin of goals, what we have to explain is the setting up of a system in which a lot of different and essentially distinctive instructions are woven together to a course of action which tends towards a definite end-point, or at least in a definite direction. How much of a problem is it to account for this? There have recently been two studies which suggest that some degree of coherence of disparate instructions into a degree of orderly behaviour, some degree of ‘canalisation’ of the resultant activity into a fairly definite direction, may occur spontaneously.
Stuart Kauffman set up a system which one can think of as a large number of light bulbs, controlled by on-off switches. The switches were connected by wires in such a way that there were two wires coming inwards to each switch, and the connections were made quite at random. It was also decided, by a random process such as throwing a dice, whether a light would be switched on when the lights from which it received signals were both on, or when they were both off, or when one was on and the other off, and so on. This system seems about as random and chaotic as it can be made. Kauffman tried the effect of turning on a random set of lights, then letting the whole system develop according to the rules built into it. He was astonished to find that in a surprisingly large number of cases, though not in all, the system very soon got into an orderly state, in which it went through a cycle, with one set of lights on, then changing to another, and to another and another and so on, but eventually coming back to the first set, after which the process was repeated. This is quite a high degree of orderliness, coming unexpectedly from a random set-up.
The other example which suggests that some degree of order may appear spontaneously is a theoretical calculation by Stuart Newman. He showed that in a system containing a large number of enzymes, with the particular characteristics that biological enzymes normally have, and operating under the sort of conditions we find in living things (in particular with low concentrations of their products), then whatever the conditions from which the system starts, it would soon follow one or another of a very small number of alternative paths of overall change.
These suggestions about the spontaneous origin of order from chaos—spontaneous formation of goals—are still very recent and little understood. I think they are interesting in that they suggest that during evolution natural selection does not have to do the whole job of producing orderly goals of behaviour from a disorganised collection of immediate responses to haphazard instructions. However, even if natural selection is presented with a certain degree of spontaneous order as a basis, there is no doubt that well designed goals such as the running-away behaviour of horses, have been moulded and perfected chiefly by the fact that individual horses that have behaved in this way have succeeded in leaving more offspring, thus passing on their propensities to later generations.
But if an animal always behaves in accordance with one definite unalterable goal, how much of a mind would we be inclined to attribute to it? Surely we wouldn't think it was being very clever. In fact, we might be tempted to say it was indulging in ‘mindless repetition’. We would be much more tempted to think the animal had a worthwhile mind if it had at least two goals, and followed one or the other in appropriate circumstances.
Let us return to the horse which may run away or stand up and fight. We might discuss the situation in terms of a visual model, similar to the one I mentioned in my first lecture when I was discussing embryonic development, and went on from that to the problem of free-will. I suggested that one could consider the development of the different organs in the body, such as the brain, heart, muscles and so on, in terms of a landscape containing a branching set of valleys, which I called chreods, separated by watersheds. We can use the same sort of model to consider the development of different types of behaviour, directed towards different goals. A horse as it grows up has, let us say, the two possibilities of running away or standing and fighting. Horses at their present state of evolution are born with a tendency towards the running-away type of behaviour, and as they get older and more experienced in this mode of activity it probably gets built into them more firmly; it becomes more strongly chreodic, or more and more difficult for them to fall into the other behaviour and stand and fight. But clearly they would be showing more mental ability—and it would also be better for them from the point of view of natural selection—if they could run away from those animals they could be certain of outdistancing, but also adopt a stand-up-and-fight tactic to an animal that is faster than them and which they could not escape.
Thus the evolution of the mind must involve not only the formation of the goals, but also the development of alternative goals, and the ability to pick the appropriate goal under particular circumstances. In terms of our landscape model, natural selection will be attempting to produce a set of valleys which are definite enough, but which are separated only by low, rather than high and steep sided, watersheds. In fact it will be advantageous to the animal if the normal state of its central nervous system—its mental condition—corresponds to a point not at the bottom of one of the valleys, but some way up the hillside though perhaps not on the crest of the watershed. Then it can relatively easily move down into the most appropriate channel of behaviour to meet the particular circumstances with which it is confronted. In my first lecture I described the characteristic of the situations in which we feel we have to exert free will as being poised on a watershed between two or three alternative courses of action. The argument I have given here shows how the forces of evolution, operating through natural selection, will bring the mental apparatus of animals into such situations; that is to say, free will appears as a natural product of biological evolution.
Any nervous system which could function as a primitive mind in lower animals must have had certain characteristics if it were to be capable of evolving into the higher types of mind we have just considered. I shall have to skim over these very rapidly if I am to get on to another point which I want to make. But we can say that, at the most primitive level, it must have had a perceptual apparatus which incorporated a ‘prior knowledge’ which enable it to recognise single instructions from its surroundings, and to react appropriately to them; for instance, biting at and eating something recognised as food. As a first step in combining a number of different instruction-responses into a chreodic path to a more complex goal, it could perhaps get some assistance from the sort of order-out-of-chaos which Stuart Kauffman and Stuart Newman have been exploring. But surely it could not get very far in this direction without having some system of storing up, in a memory of some kind, the various activities it could do, and being able to pull them out again, and combine them with each other in all sorts of different ways, to see how they fit together. Do actions in some combination or sequence dovetail into each other so as to achieve a worthwhile goal—worthwhile for natural selection? The problem of mind—being intelligent—at this level is not only to find new ways of attaining already accepted goals, but puts a premium on the still greater flexibility of discovering new goals.
I will tell the tale of the evolutionary origin of the birds; or rather, one of the more plausible tales, because I don't think the experts have quite decided exactly how it did happen. But one of the ways it may have happened concerns a group of little reptiles, rather like lizards, which had larger hind legs than forelegs, and which normally ran about on these back legs. Suppose they started using their forelegs to work up speed when they were running away from a nasty bigger reptile who was trying to catch them. And suppose the scales on the arms grew longer, into something a bit like feathers, to help them get the benefit of beating the air effectively to push them along. And natural selection pushed this development further, until, one day, some of them found themselves taking off, and becoming airborne. It must have been very disconcerting; they probably ran the risk of crashing in considerable disorder, and getting gobbled up. But a really clever little lizard, full of mind, must have said: ‘Hey, we've got something here’, and set about finding how to fly. To attain this brand-new goal, he may have had to change quite a lot of his previous routines; for instance, beating his arm-wings in unison instead of one after the other in time with his legs. In order that such an evolution could be possible, his mind had to be able to do two things. It had to be able to re-organise itself around a new sub-goal, to fly, within its old main goal, to escape; and it had to be able to re-arrange its detailed activities so as to achieve this new sub-goal, to change the timing of its arm movements, for example.
Now evolution by natural selection does not reward only flexibility. Certain shellfish which live in deep mud have been able to go on successfully living in deep mud unchanged since the Cambrian era till today. But evolution does also reward flexibility, when it comes off. Our clever lizard started the whole kingdom of birds, one of the main types of higher animals. It is in this context, I think, that we have to see the origin of human language, which was the point I wanted to get on to, because with the evolution of language, the whole nature of the best minds to be found in the living world is profoundly altered.
I shall not discuss the evolutionary origins of language in any detail, because I think Tony Kenny will be talking about it tomorrow. I just want to make, quite briefly, one or two points. In the first place, language is obviously a very powerful instrument in the enterprises of re-organising and re-structuring of older ideas and activities which are necessary for flexibility in forming and attaining goals. The use of symbols, such as words, is a very convenient means of access to a memory store; and the arrangement of words into syntactical sentences is a good way of examining the structural relations between those items. To get an idea of the power of the method, compare the rate of improvement of a human skill which can be handled with symbols, such as the ability to solve mathematical equations, with that of one which cannot, such as, say, high jumping. Both do improve as time passes, but the first, which can be taught by words, improves enormously more rapidly than the second.
The appearance of symbolically transmitted culture brought about a speeding up, by orders of magnitude, of the processes of evolution in the species which enjoyed it. I have discussed this in several books since Julian Huxley, and I first suggested some thirty years ago that language amounts to a new and faster genetic system. I shall not labour the point here, but I want to remark that the advantages of cultural transition were not obtained by mankind without a price being paid. When the audience was asked to submit questions at our open discussion, someone referred to Arthur Koestler's suggestion that the recent evolution of man's brain incorporates a basic anatomical flaw, which is the cause of the many ills which have persistently beset civilisations based on transmitted culture. I think that it is not necessary to look any further, to find the root of these troubles, than to the fact that symbolic transmission is an evolutionary novelty, and that man is still trying to master this new skill, and is floundering about in a thoroughly clumsy way, like the first bird-lizards who found themselves unexpectedly air-borne.
The main difficulty in becoming a skilful performer, who never loses control and crashes, arises I think from the method mankind uses for turning a physical occurrence, such as a noise, into a symbol, a word which has a meaning. In practice this essential conversion depends on associating the noise, in the mind of the very young baby who is being initiated into the world of culture, with some sort of authority which controls its acts, such as a parent. I have argued in detail in my book The Ethical Animal that it is from this process—noise becomes word by association with personal authority—that man derives his characteristically human notions of a personal God, and of self-transcending criteria of good and evil. But the process, at this stage of man's evolution, very often does not work smoothly. It may give rise to a Freudian ‘super-ego’, and all sorts of irrational obsessions, fears and hatreds. There is no reason to expect that keeping aloft in the realms of spirit is any easier for man than flying through the air was for lizards. Man has already taken some nasty tumbles, and he may finally crash fatally; but on the other hand, our descendants may attain as much mastery over the world of good and evil, belief and freedom, as did the lizard's descendants, the sea-gull and the kestrel, over the thin and dangerous air.
One final point. This lecture was announced with the title: ‘Does Evolution have a Goal?’ When I came to write it, it did not turn out quite like that. I had discussed that before, in The Ethical Animal, and I wanted today to say something different. But I should like to finish by asking whether there is anything inevitable, or foreseeable, about the appearance in evolution of the human mind, which is so much a product of the cultural mode of socio-genetic transmission.
The cybernetic mechanism of evolution which I have sketched earlier, in which phenotypes form goals, and populations are put through the hoops of natural selection to find those members which have goals which they are able to achieve, would be expected to produce all sorts of different life-styles and ways of succeeding in them. One could regard the whole kingdom of living things as a series of feelers extending in all directions to explore the realm of possible modes of staying alive and reproducing. Now I think one can say, with hindsight, that it is obvious that a cultural-symbolic mode of transmitting instructions from one generation to the next is not only a possible mode, but one which would provide much greater flexibility in fewer lifetimes than the mode employing the DNA-RNA-protein machinery which most of the living world relies on. It follows that, if the realm of possible life-styles is being explored all over, something will eventually stumble on this possibility.
But I see no reason why the cultural-symbolic mode should have taken just precisely the form which it actually has taken in the evolution of man. The essential point in it is that something or other, which is transmittable from one individual to another faster and more frequently than DNA, should become endowed with the power of being a symbol, which conveys instructions. Noises, or visual signs like letters or ideograms, are good candidates for suitable carriers of symbolic meaning. But I am not sure whether there is any compelling a priori reason why the conversion of these neutral physical stimuli into symbols should have been by associating them with personal power or authority. Could there have been an evolution of another type of language, in which a noise became a word, not from its association with a parent who controls one's behaviour, but, perhaps, by being associated with the definiteness of different objects of perception, which the baby is also discovering at about the time it learns to talk? The noise ‘cup’ would get that extra something which turns it into a symbol, not by derivation from the authority of a parent who was trying to make you drink out of it, but by association with the realisation, which must be extremely powerful and impressive when it first dawns on the awakening mind, that certain groupings of sensory, inputs add up to something which you can pick up as a separate entity, which can contain fluids, and so on. If symbols and language had evolved in this way, rather than in the way they have actually evolved, our minds would have a basic tendency towards polytheism, seeing God in everything, and a non-personal, non-controlling God at that, instead of towards the monotheistic Law Giver who has such a hold on the Man who has actually appeared on the stage of evolutionary history.
Perhaps, indeed, something of this second course has entered into the evolution of language as we know it, and slightly, though I would say not sufficiently, blunted the cutting edge of the dangerous weapon of authority-based symbolisation.
I think the points which will be most interesting to us, who are for the most part not biologists, in the consideration which Wad, himself an eminent biologist, has given to the nature of the evolution of the mind, are going to be the points he brings up to avoid being forced into a reductionist position. He is at pains to say that evolution is to be accounted for not only in terms of Darwinian theory but also in terms of information theory; and then he rapidly goes on to refine this and say that information theory isn't the stuff that goes on in Bell Telephone laboratories, it is not negentropy but rather gentropy, throwing away most of the stuff we are told, as being mere info, and laying all emphasis on just the know-how of the important things to do. Here, I think, in the rejection of the sort of rather pale academic information and the emphasis on the real full-blooded passions of the mind, we might once again discern at work in Wad's mind, the influence of David Hume. This move towards the imperative rather than the indicative mood which is stressed by Christopher is of very great concern to us, as giving us some idea what the mind is, and also the questions we need to ask in coming to terms with the facts we know about our ancestors and their pre-history.
The key notion which we haven't yet illustrated enough is that of goals. Wad wants to say it is just not simply an instruction—after all, those rather boring clays are able to carry out certain self-replication instructions and this he is prepared to reject, if it's offered as a typical phenomenon of mind, as being merely mindless repetition. Rather than this, we have got to have a certain choice between alternatives; and he is very much concerned to argue that there should be some element of freedom in this choice—both in the account of the early ancestors of the horse, and in the account of the way the birds came. In each case, he quite deliberately uses very personal language.
This point I want only to allude to, because there is not time to extract any philosophical meat out of it; but it is very significant in our attempt to make out what lessons we should learn from evolution, what are the questions that we ought to ask. What we are being shown is that there is some element of free choice which characterises even rather primitive living organisms, but more pre-eminently those that we are prepared to ascribe minds to. These are subjected in the first and classical case to the discipline of natural selection, and then, with man and more or less with man alone, to the further form of information control which is constituted by the use of language. Like Wad, I shall not trespass on this because it is Tony's preserve, and it would be a pity to broach the subject before him; but I just want to raise one point where I think I can quarrel with Wad without stealing any of Tony's clothes.
We have a new version today of the origin of sin. No longer is it either that Adam needed apples or that Prometheus stole the fire from the gods. It is not even the normal fashionable Freudian account that one can read week by week in the Sunday papers, which is something to do with ‘potty’ training and things like that. Nevertheless, like that, it goes back to one's very early years, but it is in the instruction in the use of language that all our troubles are said to arise. It is authoritative-based symbolisation which gives rise to our self-transcending criteria of good and evil. These, although a powerful force for good, have somehow come adrift and made us subject to quite disastrous lapses of judgement and temper. I don't think this is an adequate account for a number of different reasons; I think there is a false antithesis between the transcendent concept of right and wrong which, I agree, the symbolic nature of language enables us to handle, and what Wad would rather have us adopt, some sort of self-generated concept of right and wrong. (If we are going to have the word ‘transcendent’ I suppose we should also have the word ‘immanent’.) These terms are not opposed. Although the use of language is something which does enable us to form the concept of right and wrong, it is not either essentially, or even as a matter of contingent fact, instilled simply by authority. Some authority no doubt, but also very largely an element of exploration. After all, no amount of authority will teach some people to speak; and the schoolmaster can use his rod but fail to instil anything into a great many impenetrably thick intellects which, if nothing else, stand as counter-examples to Wad's thesis.
I am really surprised that John will not allow me to associate the idea of sin with the acquisition of language. I thought I was simply rephrasing the Book of Genesis. After all, the Fall of Man and the expulsion from the Garden of Eden followed eating the fruits of the Tree of Knowledge; and if that isn't acquiring language, I don't know what is.
Now, to go back to John's point about goals and personal choice. I was quite deliberate in using personal language in this connection, as he said I did. I think I have argued at one of these lectures—I have certainly argued it in other places—that even in the apparently simple act of perception, something is involved that is very similar to purpose. The recognition of an item in perception involves accepting that what you are perceiving is near enough to some internal model, which has a chreodic character, so that it can act as a ‘centre of attraction’ into which anything that falls within a certain neighbouring area of variation gets sucked in. This bringing into line of nearby variants is something very like the behaviour of a system which has a goal. So if you believe, as I do, that science is based on experiments, on experiences involving perception, not on hypothetical constructs such as atoms, electrons and so on, then I do not think one need be frightened to introduce ideas like personal choice, or at any rate ideas like goals, right at the basis of one's whole concept of scientific understanding, because such ideas come into the very basic notion of perception.
May I raise another point, of a rather different kind? You touched on the question whether pre-biotic evolution, or should one say the inorganic precursor of evolution, would inevitably or most likely produce life. This is a question which cannot possibly be answered without reference to the prevailing conditions and how long you are prepared to wait. There is, for instance, the ‘nitty-gritty’ question of whether there's any water about. It looks as if the sun, for instance, is a great deal too hot to permit the evolution of life, even over a very long time. The moon is too cold: maybe there was life there once but we don't think the conditions are right any longer. These are issues which one can only discuss, it seems to me, in coldly physico-chemical terms; I doubt if anyone is going to arrive at the answer by purely information-theoretical reasoning, without reference to the way things were. That's why I felt a little uneasy when you dismissed the physics and chemistry as fallacious reductionism. Information theory, which I agree we now have to use, wouldn't be relevant until there was something about which to information-theorise, a self-replicating system of some sort, and no-one has yet accounted for the origin of such systems, as far as I know.
Like John, I welcomed it very much when Wad drew our attention to the ambiguities of the word ‘information’ and showed the dangers of applying Shannon's information theory to the sort of things we are talking about when we use the word ‘information’ in ordinary language. But I thought that Wad then fell into the same error when he introduced his new word ‘instruction’. He was using ‘instruction’ in such a broad sense that while it is a case of instruction if I get into a taxi and tell the taxi driver to drive to the Carlton Hotel, it is equally a case of instruction if I get into my own car and shift the gear lever and turn the steering wheel. If we are talking about the evolution of mind, we're surely talking about what makes the difference between taxi drivers and taxis and, with all respect, I thought there wasn't a word in Wad's paper to explain the evolution of mind.
There can be at least two views about what mind is. In these discussions there have been those of us who wanted to identify mind with consciousness and those who wanted to identify mind with such things as the ability to use language. In either case, if one has to explain the evolution of mind one must show how beings which clearly did not have minds (which clearly did not have consciousness, for example, or which clearly did not have language), could turn by processes of natural selection into populations which did have minds (which did have consciousness or which did have language). I didn't hear any point in Wad's paper where he took such a case and showed how it could come about. I thought he was going to do this when he began talking about the evolution of birds but instead of using the evolution of birds to explain the evolution of mind, he used, as John pointed out, the presence of mind to explain the evolution of birds.
I suppose that eventually we shall have to tackle this problem of trying to define the mind. Tony has said that there are some who want to define it as the use of language, and others want to define it in terms of consciousness. Now I should not want to define it as either of these. Certainly the use of language is something which certain types of minds can do, but to me that does not mean that all types can. Consciousness is something I know very little about. Whether the first ‘clever little lizard’ was conscious or not I can only guess; possibly it is easier to suppose that he was. But honestly it seems to me that we really don't know, and I don't see how we ever could know.
I am not prepared, as yet at least, to give a definition of mind. I tend to see it as in some way connected with the integration of a lot of intentions or goals, or with the integration of a lot of responses to instructions, into complex systems which lead to some definite end-point. Or rather, I'd say that any but the most absolutely primitive mind has got to be able to integrate responses so that they can lead not just to one, but to several different end-points; it must really have alternative goals. Now, whether they are conscious goals or not seems to me a question you cannot usefully ask, because there is no way of getting an answer to it, except about oneself, and about people who can talk to one (supposing one believes what they say); while it seems to be clear that there are many animals which can perform the sort of integration of responses I refer to but which do not use language. When I said something about the origin of language, I was not, in my opinion, discussing the origin of mind, but only one stage in the evolution of mind. However, Tony will be coming back to the question of language, and when I reply to his lecture we shall be able to return to this theme.