Discontinuities

Sixty years ago, when Alfred North Whitehead delivered the lectures that were published as Science and the Modern World, he was famous as a penetrating philosopher of mathematics, the teacher and later the colleague of Russell, a man of wide learning who had turned to metaphysics and developed a new system so profound that few dared criticise it; he was also an educational reformer and an upright man loved by his many friends. All in all, the very model of a Philosopher, academic indeed, but one for whom the epithet could only be a mark of the highest praise. This book was reprinted 11 times up to 1953, and at least twice since then. There can never have been such a tribute to pure thought. I won it as a school prize and was utterly defeated by it; 45 years later I find the argument difficult at all times, and in several chapters impenetrable by reason of its technical abstruseness. Apart from these, which I cannot judge, the fault does not lie in Whitehead’s style, which is lucid and sensitive – it is the density of the argument that makes demands on the reader. Of all those copies that were sold before, and doubtless will continue to be sold, very few can have been studied with such painstaking attention and pencilled emphasis as the copy of the 1953 reprint I have borrowed from the Cambridge University Library, and even in this case the original owner has faltered one-third of the way through and is lost without trace.

It should already be clear that this is no exposition of the wonders of science, nor is the ‘modern world’ the highly industrialised world of the present. For Whitehead the modern world started with Copernicus, Vesalius, Bacon and Descartes and started, moreover, on the wrong foot. This is the thesis that runs through his historical chapters; the squalor of the post-industrial revolution is in part attributable to lack of principle which allowed the search for knowledge to be divorced from ethical considerations. The materialism so wholeheartedly embraced by physicists from Newton onwards utterly excluded the operations of mind from the processes of science, to the grave detriment of human society. It would be unjust, however, to suggest that Whitehead blames science for everything that has gone amiss, or merely yearns for a lost Arcadia. For one thing, no sooner does he seem to be falling into this trap than he pulls himself up to admit the danger of his adopted position. This is the work of a man who writes nothing without thinking through the consequences, and it is enormously worth reading if only to experience the mind of a master. Nevertheless, when all is said and done, I find I cannot accept his central thesis, not because the analysis is demonstrably faulty, but because it is sterile.

Likely enough, if he were writing now, Whitehead would not be so perturbed as he was then about the state of science. He could not have chosen a worse moment to talk of the imminent break-up of the physical world-picture. The discoveries in quantum theory did indeed seem to threaten the comfortable old post-Newtonian materialism which was based on bodies moving comprehensibly under the influence of their mutual interactions. Perhaps this was illusory and all processes were, on the atomic scale, discontinuous – the particle disappearing here and reappearing there with no intervening existence. This was, to him, both a threat to the magnificent edifice built on Newton’s foundations and at the same time a faint source of hope that a new outlook, preferably his own, might offer an escape from incomprehension. What he could not have known was that at the very time he was writing Heisenberg and Schrödinger and Bohr were cooking up one of the greatest of all revolutions in thought. The deterministic materialism of Victorian science was wholly overthrown by the new quantum mechanics. Before 1900 an unsophisticated physicist, if he had permitted himself belief in God, could have imagined that God’s view of the universe was very much like his own – matter existed out there and anyone who cared could look at it. I suspect that most people in their hearts believe something like this nowadays.

With the advent of quantum mechanics, however, this view of things, from being merely naive, became untenable. In order to calculate correctly the behaviour of matter on the atomic scale of sizes an entirely new theory is needed, and the new process of calculation, by way of Schrödinger’s equation, carries with it some very surprising implications. One of them is that to predict the outcome of an experiment, given the initial arrangement of particles, we must to some extent forgo knowledge of what happened between the start and the finish. So much so, indeed, that when discussing the behaviour of atoms and electrons we may doubt whether these entities are more than convenient fictions introduced as part of the paraphernalia of the mathematical theory. But there is worse to come: it is easy to devise experiments involving two or more observers, and to find that their combined observations only make sense if their instruments (or eyes, or ears) are analysed together. If we make the mistake of supposing that each observer can examine the experiment independently, the equations permit observations to be made that are mutually incompatible: put all the observers together in one grand Schrödinger equation and a sensible answer emerges. The physical theory works superbly, flawlessly it is fair to say, when applied to material problems: but it carries the implication that we are not detached observers, neither detached from the thing observed nor detached from one another. It is an enormous intellectual achievement to have devised so precise an instrument of mathematical description, a mere correlation of observations, everywhere applicable, without the foggiest idea what it all means.

Expressed in this way, modern physics conforms more closely than the physics of Whitehead’s time to the philosophical objectivism he favoured. This is not to be confused with materialism, though I think it is possible to subscribe to both concepts simultaneously. Objectivism is the belief ‘that the actual elements perceived by our senses are in themselves the elements of a common world; and that this world is a complex of things, including our acts of cognition, but transcending them.’ Modern physics forces us towards this position, but there is an intermediate and defensible point of view that I may call ‘materialistic objectivism’: the material world is a real thing, which in appropriate circumstances can generate the property of consciousness, but this consciousness is part of the material world and its perceptions of that world are incomplete and imperfect, revealing the world as if, say, through a badly-adjusted black-and-white television set. Hence the need to evolve a theory of observations, such as quantum mechanics, that gives the right answer without necessarily enlightening us further about the nature of the material world. The point of difference between these two views lies in the relationship of mind and matter. Whitehead says, ‘the objectivist holds that the things experienced and the cognisant subject enter into the common world on equal terms’; the new brand of materialist hopes to discover one day that consciousness is an emergent property of otherwise unconscious matter. That is to say, Whitehead’s view is dualistic, giving equal weight to the distinct concepts of mind and matter, while materialistic objectivism, which is very close to Lloyd Morgan’s ‘emergent evolution’, is monistic. It is clear from Morgan’s writings that he was no follower of Whitehead, while Whitehead, for his part, acknowledges Morgan’s work in his preface but refers to it no further. I am confident that most modern scientists, if forced to choose between the two, would come down in Morgan’s favour. The advances, apart from quantum mechanics, that have swung the argument in this direction are in the field of biology.

In 1925 Whitehead could write without too much exaggeration: ‘for the first time physiology is asserting itself as an effective body of knowledge, as distinct from a scrap-heap.’ This was the moment to expose the fallacies of a crass materialism so as not to repeat in biology the mistakes of mathematical physics. He deserves extended quotation, for this is the heart of his belief:

The doctrine which I am maintaining is that the whole concept of materialism only applies to very abstract entities, the products of logical discernment. The concrete enduring entities are organisms, so that the plan of the whole influences the very characters of the various subordinate organisms which enter into it. In the case of an animal, the mental states enter into the plan of the total organism and thus modify the plans of the successive subordinate organisms until the ultimate smallest organisms, such as electrons, are reached. Thus an electron within a living body is different from an electron outside it, by reason of the plan of the body; but it runs within the body in accordance with its character within the body; that is to say, in accordance with the general plan of the body, and this plan includes the mental state. But the principle of modification is perfectly general throughout nature, and represents no property peculiar to living bodies. In subsequent lectures it will be explained that this doctrine involves the abandonment of the traditional scientific materialism, and the substitution of an alternative doctrine of organism.

Here we have an example of Whitehead’s besetting weakness: he sees his task as a philosopher to lay down general principles for the progress of knowledge. Having found fault with past science for eliminating mind from its considerations, he cannot resist seizing on every perceived difficulty – relativity, quantum theory, organic life – as an opportunity to push contemporary science in the desired direction. History has been unkind to him: not only have scientists made astonishing advances without his help, but they have begun to find for themselves the limitations of crude materialism and recognise the possibilities of refinement. When one looks at the major scientific advances over the centuries to see the part played by the contemporary philosophers, it turns out to have been virtually nil, and for good reason. As often as not, the point of attack for the scientist is not a generalised malaise, such as the philosopher will probably perceive even more clearly than the scientist: it is the resolution of some small discrepancy or the natural outcome of progress on some relatively limited front. The scientist cannot proceed on the basis of large generalisations but only on the basis of specific ideas where his imagination and technique are matched to the problem. It is no good saying he ought to do this, or he ought not to do that: being very restricted in his skill, he will do what he can – as Medawar has stressed, research is the art of the soluble – and leave others to build on it or clear up the mess. And the scientist is ready enough to leave the latter task to the philosopher.

Let us return to the problem of life. The passage I have just quoted comes after Whitehead has rejected vitalism as an unsatisfactory compromise designed to safeguard free will in a mechanistic world. The gap between living and dead matter is too vague to allow this escape route, as he would assert now even more confidently than he did then. The developments in the intervening years, especially of biochemistry and molecular biology, have left little choice but to treat primitive living creatures on the same terms as one would an assembly of chemical compounds. Of course, even the most primitive cell presents a structure and organisation immensely more complex than anything accessible to the chemist, but such analysis as has been made shows there to be little merit in trying to draw a line between the non-living and the living. The reductionist procedures of physical science have been so enormously successful that the elucidations of the chemical structure of proteins and of the double-helix DNA in the Fifties have proved to be the start of a revolution in thought as important as any in the past. Already a significant start has been made – for years the pages of Nature have been full of new discoveries – towards understanding the code in which is written, on the DNA chain, the complete specification of the body it describes. How that code is translated into action, and the body itself constructed, will take a long time to work out, for it is bound to be a very intricate process. The DNA molecule is surely not a blueprint, but more like an organisation chart, laying down the rules governing how each new unit in the structure shall react to what is already there. But no one believes that a new scientific principle, a vitalistic force, must be introduced at this stage. To put it bluntly, the living body differs in its vast complexity of organisation, rather than its fundamental mechanism, from the stuff of the inorganic world. Of course, this is an act of faith, but it is a defensible belief and one that seems to me to be entirely at odds with Whitehead’s view.

Nevertheless the materialists have not triumphed yet, nor will they ever, I think, because although their materialism will cope with life in an amoeba, or even perhaps a mouse (I do not wish to commit myself on this point), it cannot cope with that concomitant of certain forms of life – mind. In particular my self-awareness, which I am prepared to allow is shared by other humans and possibly some animals, is a property lying entirely outside the scheme of physical science. The basic assumption of science is that there are certain facts of common observation on which all reasonable people can agree, and which repay communal investigation. These facts may include observations of the behaviour of individuals or societies, and even the expressed thoughts of individuals, but not what was going on in the conscious mind of the speaker. For we have no means of entering into the consciousness of another, nor is there any manifest property of matter that gives the smallest clue to how conscious mind could come to be. The committed materialist accepts this, but argues that even though we are ignorant of the mechanism, mind is still a property exhibited by certain complex systems and none the less constrained by the fundamental laws of matter; free will is an illusion whose very existence is mechanistically predicated.

There is a serious flaw here, to analyse which brings us at last to the concept of emergence. This is Lloyd Morgan’s term, long since forgotten, though the ideas involved have become increasingly important in scientific thought. The myriad different patterns of atoms as they are arranged in molecules are not inherent in the atoms themselves. For instance, when silicon and oxygen are combined to form a crystal of quartz, there turn out to be two arrangements differing only in that they are mirror images of each other, just as the left hand is a mirror image of the right. The isolated atom has no structure to make the mirror image different from the thing itself and it is only when they arrange themselves along helices that they take on the appearance of a left-handed or a right-handed screw thread. This quality of ‘handedness’ is in no sense embryonically present in the atoms – it comes into being in the process of chemical combination. In this case it is difficult to imagine oneself proceeding gradually from a collection of separate atoms to a crystal of quartz, but there are many examples of systems where the change in character can be brought about smoothly, and yet is a change of kind – a paradox that needs to be explained. One such change occurs in iron. A piece of iron can be magnetised at ordinary temperatures but loses this quality on heating to a dull red heat. In its high-temperature form the property of magnetisability is completely absent, not just too weak to be observed: but as it is cooled there is a well-defined critical temperature at which magnetisability appears, very weakly at first but becoming rapidly stronger with further cooling. We must distinguish between quantity and quality. As the iron is cooled the quantity of magnetisation can take any value in a continuous range: qualitatively the iron is either not magnetisable or magnetisable (however feebly). There is no question of the degree of magnetisability slowly becoming appreciably large as we approach the critical point from above: the way it suddenly begins to shoot up at this point confirms that it really was zero before.

I have stressed this point because it is so easy to argue that any new quality, like consciousness, must have been embryonically present in all things, but only plays a significant role in the higher creatures. By analogy with the very common critical phenomena of which the behaviour of iron is a typical example, it is much more likely that a certain level of organisation is required before the first flicker of consciousness appears on the scene. If we knew how to do it, we should be able to divide all organisms into the haves and have-nots: or would we find that there are so many different varieties of consciousness that no simple classification is possible? For my purposes it does not matter: it is enough that this peculiar property of higher organisms should be the outcome of complexity, having no parallel in the properties of the constituent parts.

However strongly convinced we may be that consciousness is a natural outcome of high organisation, without changing the basic laws as I think Whitehead felt to be necessary, it still remains that everything about the qualitative shift to consciousness remains enigmatic. Because of this we are in no position to deny that it may be accompanied by other new effects, just as the handedness of a quartz crystal is accompanied by the ability to become electrified under pressure. There is simply no case for dismissing as illusions the possession of free will, or the religious impulse, or any other attitude to existence that distinguishes us from the brute creation. Whatever reservations I may have about Whitehead’s attempt to impose philosophy on science I have none about this approach to matters of feeling and religion, which is ‘the vision of something which stands beyond, behind and within the passing flux of immediate things ... something which is the ultimate ideal, and the hopeless quest’. And again: ‘the vision claims nothing but worship.’ This is something that I, who have never felt the need to worship, can see in the lives of those who are truly religious. There is nothing in this that is incompatible with my science, and as a scientist I must accept the possibility that there are those who can sense something which is denied me, just as some are colour-blind and others deaf to the emotional onslaught of music. But I am grateful for clear expression of what religion means to a man of high intellect and pure heart, in contrast to the triviality of what all too often passes for piety. Let us put aside Whitehead the mathematician and Whitehead the philosopher and leave the last word to Whitehead the believer: ‘The worship of God is not a rule of safety – it is an adventure of the spirit, a flight after the unattainable. The death of religion comes with the repression of the high hope of adventure.’