The Unnatural Nature of Science
Page 18
The N-ray affair had a parallel in 1989. Jacques Benvaniste, a senior immunologist working in a French government-sponsored research laboratory, published a paper in Nature claiming that, in effect, water had a memory. His experiment was to dilute a particular chemical so much that, according to classical chemistry, the solution would have no trace of the original substance left; and yet this hyper-dilute solution was found to have a similar biological effect as the original undiluted solution. Benvaniste’s claim was that the chemical had imprinted a memory on the water and so its biological activity persisted in its absence. This was regarded as a great boost to homeopathy, which is based on the idea that certain medicines become more potent the more they are diluted. Surprise, and outrage by some, was the response of the scientific community to seeing such a paper published in a most prestigious scientific journal. But part of the deal in accepting the paper had been that Nature itself would visit Benvaniste’s laboratory. The editor, together with a magician (a well-known exposer of hoaxes) and an ‘expert’ in scientific fraud duly arrived. They found no evidence of fraud, but Benvaniste’s claims could not be substantiated. Benvaniste, for his part, claims that the trial was unsatisfactory and stands by his original claim. And there the matter rests. Like N-rays, it may quietly disappear, but more likely it will burst forth again with equally unpersuasive evidence as another example of Langmuir’s pathological science.
Yet there may be something of a puzzle remaining. The idea of all bodies attracting each other was a remarkable imaginative leap by Newton, particularly since the attraction was not, in his theory, mediated by any other medium. So when Newton produced his theory of gravity – that bodies attracted each other at a distance with a force proportional to their masses – it was greeted with comments that you might think would be used by scientists like myself commenting on paranormal phenomena. ‘It pleases some to return to occult qualities … but because these have become unrespectable they call them forces, changing the name …’ wrote the great Leibniz. To Leibniz, gravitational attraction was ‘a senseless occult quality … that it can never be cleared up, even though a spirit, not to say God himself, were endeavouring to explain it.’ The Dutch scientist Christiaan Huygens was also very critical: ‘That is something I would not be able to admit because I believe that I see clearly that the cause of such an attraction is not explainable by any of the principles of mechanics or of the rules of motion.’
Newton responded with typical vigour and said that Leibniz denied conclusions without taking fault with the premisses; that Leibniz’s arguments were founded upon metaphysical hypotheses, whereas he, Newton, was interested only in experiments. Moreover, he charged that Leibniz took refuge in emotive expressions such as ‘miracles’ and ‘occult qualities’ so that he might denigrate universal gravity. Yet, as Newton wrote,
It is inconceivable that inanimate brute matter, would without the modification of something else which is not material, operate on, and affect other matter without material contact … That gravity should be innate, inherent and essential to matter, so that one body may act upon another at a distance through a vacuum without the mediation of something else … is to me so great an absurdity that I believe no man who has in philosophical matter a competent faculty of thinking can ever fall into it.
But, he goes on: ‘Gravity must be caused by an agent acting constantly according to certain law but whether this agent be material or immaterial is a question I have left to the consideration of my readers.’ In his Philosophiae Naturalis Principia Mathematica he made his position absolutely clear: ‘I have not been able to deduce from phenomena the reason of these properties and I do not feign hypotheses.’
Newton’s position is fundamental to understanding the nature of science. Gravity was not an occult quality but a postulate from which testable observations could be made and which provided an economical way of explaining in a consistent and logical manner a very large number of phenomena. What was at dispute was the postulate to explain the observations, not the observations themselves, and he had, he admitted, no satisfactory explanation for gravity (Chapter 4). Darwin, too, had to make an assumption, about biological variation, for which he had no explanation but excellent evidence. In a way their situations were not that different from a perception of modern quantum mechanics: as Murray Gell-Mann, one of the founders of modern physics, says:
All of modern physics is governed by that magnificent and thoroughly confusing discipline called quantum mechanics invented more than fifty years ago. It has survived all tests. We suppose that it is exactly correct. Nobody understands it but we all know to use it and how to apply it to all problems: and so we have learned to live with the fact nobody can understand it.
It is just one of the painful aspects of science that scientists learn to live with: they recognize when understanding is absent, but at least they have the phenomena.
Unlike science, religion is based on unquestioning certainties. It is neither easy nor natural for most people to live with uncertainty, and religion can provide a solution to many problems, particularly moral ones. Thus all religious belief can be regarded as natural – in the sense that most societies, both present and past, have had religious beliefs that can provide an explanation of its members’ origins and make some meaning of their lives. This presents a problem for scientists who have to reconcile their views with religion or reject it, since, as I will try to show, religion and science are incompatible. There is also another basic problem, for, as Tolstoy pointed out, ‘Science is meaningless because it gives no answer to our question, the only question important for us: “What shall we do and how shall we be?”’ Tolstoy was right in that science cannot provide moral guidance.
These are problems with a long history. As we have seen (Chapter 3), Averroës argued that the cultivation of science should be totally independent of any tenet of Muslim creed. He avoided a scientific discussion of miracles reported in the Koran: ‘Of religious principles it must be said that they are divine things which surpass human understanding, but must be acknowledged although their causes are unknown.’
The tradition of Averroës was taken to its logical conclusion by David Hume, who put it succinctly: ‘Our most holy religion is founded on Faith, not on reason.’ Opposing the traditional doctrine that science and religion were complementary, Hume maintained that they were mutually exclusive. Religion, he argued, is not even a form of knowing: it is rather a complex kind of feeling. Believers could not legitimately employ material events or rational arguments to support their religious belief. The religious man can only be a fideist: one who believes without recourse to science or reason. For Hume, religion simply postulated unknown causes. He was opposed to natural theology – the idea that based the existence of God on the majestic and wondrous design of nature. Reason, he considered, is limited to the realm of human experience and therefore it cannot decide ultimate questions such as the origin of the cosmos: ‘we have no experience of divine attributes or operations.’
Scientists have to face at least two problems that tend to drive them in opposite directions. On the one hand, however successful their theories may be, there will always be an irreducible set of laws or fundamental particles which must be taken as given, without any cause. There must come a point at which there is no cause, no explanation: the origin of the universe must ultimately be inexplicable and something must be taken as an unquestioned starting-point. Science can never provide the answers to everything: even when there is a unified theory that might explain everything, there must always be something – the justification for the theory, the basic postulates – that remains unexplained, unaccounted for, and scientists must accept this. This might drive some scientists to arguing that God provides the starting-point, and that God wound up the universe and set it going. But now the scientist is driven in the opposite direction, for postulating a God is to postulate a causal mechanism for which there is neither evidence nor any foundation – a postulate that cannot be falsified. A scientist
may perhaps believe in a God, but he or she cannot use God as an explanation for natural phenomena. He escapes embodied presence and perception since he is not in space and his existence cannot be demonstrated. Thus his existence has to be of a radically different character from the reality of the world. God is in this sense a non-existent entity. How can a scientist deal with a non-existent entity?
It could be gratifying, even comforting, for the scientist to find support in religion, even though it is not compatible with scientific belief. But if there were an intellectually legitimate path from the scientific world to a religious belief in something more cosmic, God-like, there is no reason to believe that the path would lead to a benevolent Christian God, or the God of any other faith.
Yet many of the greatest scientists, from Galileo to Einstein, have had no difficulty in being deeply religious. Newton even saw himself as God’s prophet and spent innumerable hours showing how the secrets of nature were hidden within the Bible. Michael Faraday’s scientific creativity was intimately linked to his Christian belief. He was a member of the small Sandemanian sect, who believed in the literal interpretation of the Bible, and Faraday thought that, similarly, scientists should read the book of nature as directly as possible, through experiment, and should avoid abstract mathematical theories. For Einstein, ‘A religious person is devout in the sense that he has no doubt about the significance of those suprapersonal objects and goals which neither require nor are capable of rational foundation … A legitimate conflict between science and religion cannot exist. Science without religion is lame, religion without science is blind.’ What he is saying is perhaps similar to Tolstoy’s statement quoted earlier.
This paradox may be understood in terms of the natural nature of religion compared to science. To follow up Tolstoy’s point, the scientist, or anyone else, without religion has to face an indifferent chaos and has to accept that all human hopes and fears, all ecstatic joys and dreadful pains, all the creative torments of scholars, artists and saints and technicians are going to vanish forever, without trace. If, as Halévy puts it, ‘Reason is insignificant as compared to the instinct by which we live,’ then some scientists are able to set aside the conflict between science and religion. For being religious need not interfere with one’s scientific activity and can even have a positive effect, so different are the two modes of thinking.
One approach, by a religious scientist, John Polkinghorne, is to view the theological enterprise as summed up in a phrase from St Anselm: faith seeking understanding. Theology is a reflection upon religious experience, following Whitehead’s definition: ‘The dogmas of religion are attempts to formulate in precise terms the truths described in the religious experience of mankind. In exactly the same way the dogmas of physical science are attempts to formulate in precise terms the truths discovered by the sense perceptions of mankind.’ However, this approach begs the key question: namely, whether religious experience is of a different kind from all other experiences. Why should religious experience be treated as different from any other experience and not be subject to scientific inquiry in the normal way? However intense and remarkable religious experience may be, that in itself cannot justify it being granted a privileged autonomy. There is nothing in religious experience that is incompatible with science; the incompatibility only arises when it is claimed that religious experiences are quite different from any other and involve, for example, supernatural phenomena such as a deity or miracles. One way out of this dilemma is thought to be that religion, like the strange behaviour of subatomic particles, may call for its own ‘special kind of rules for discourse’. But there is no justifiable connection.
A somewhat different perspective is to base religion, such as the Christian tradition, on historical evidence such as the Scriptures. This at once raises the problem of miracles: ‘Admit the existence of God, of a personal God, and the possibility of the miraculous follows at once.’ By invoking miracles it is thought possible to form a coherent picture of God’s activity in the world that embraces both the fact that in our experience dead men stay dead and also that God raised Jesus on Easter Day. Science is not in a position to contradict these special cases on the basis of its generalized investigations. On this view, miracles are seen not as celestial conjuring tricks but as signs – ‘insights into a deeper rationality than that normally perceived by us’. Similarly, it is argued that, just as in science the interesting anomaly can be an important lead in pointing the way forward, so the events associated with the life of Jesus, which have an anomalous character and are apparently inconsistent with science, must take into account the spiritual dimension and should be used as an example of this dimension. But Hume has already countered such arguments: ‘no testimony is sufficient to establish a miracle, unless the testimony be of such a kind that its falsehood would be more miraculous than the fact which it endeavours to establish.’
Some religious scientists have argued that it is not logically valid to use science as an argument against miracles, since to believe that miracles cannot happen is as much an act of faith as to believe that they can happen. In a way they are right, since consistency and universality in the laws governing nature are basic, and usually unstated, assumptions that scientists make. But such assumptions are testable and so are quite different ones from those required by religious beliefs. Like the paranormal, the evidence for miracles or the existence of heaven, hell or an after life is not sustainable within the context of science, so scientists ought to continue to deny the possibility of miracles until presented with evidence to the contrary. Those who believe that religion and science are compatible have to believe in things demonstrably unscientific and to assert the existence of entities or processes for which no shred of evidence exists.
This analysis has thus far concentrated on the compatibility between science and religion and has avoided the direct conflict that was recognized by Averroës. Scientific evidence is in direct conflict with the Scriptures. Humans, so science claims, are closely related to the apes, and women do not come from Adam’s rib. The response of a group of Christian fundamentalists has been to devote a great deal of effort to arguing that evolutionary theory suffers from serious deficiencies and that creation science, a doctrine compatible with the book of Genesis, provides a far better explanation. The creationist campaign is an attack not merely on evolutionary theory but on the whole of science, for, if its supporters’ claims about evolutionary science were to lead to it being dismissed, other major fields of science would also have to be dismissed. For example, the creationists maintain that the earth is only a few thousands of years old. If this is true, then all the estimates based on radioactivity (and hence physics itself) are false and therefore most of astronomy and geology have to be rejected. One must understand that the creationist science is Bible-based and hence linked to a set of presuppositions that cannot be altered, or proved false. Creationist science is not science if only because it precludes change in ideas; such changes are fundamental to science.
The creationists, like some of those who support the paranormal, mimic science in order to bolster their arguments. Thus the creationists lay down criteria for science and then argue that evolutionary theory does not fit these criteria. Their argument is that science requires proof and that the evidence provided by evolutionary biology does not constitute the required proof. They charge evolutionary scientists with basing their beliefs on faith, not evidence.
But, as we have seen, science is concerned not with absolute truth but providing a usable and reliable body of knowledge about the nature of the world. Change is crucial to science, but not change without good evidence. The great physicist Lord Kelvin, it will be recalled, was wrong about the age of the earth, which he too thought was not very old, because he based his calculations on the cooling of the earth; but radioactivity, an important source of heat in the earth’s core, had not yet been discovered in his day.
The attack of the creationists is based in part on the claim that evolutionary theory
cannot be falsified à la Popper. But, as we have seen, falsification is just one aspect of science – and, in any case, current evolutionary theory could easily be proved false. For example, if it were shown that many acquired characters were inherited, or that mammalian fossils were found in rocks whose age antedated the vertebrates, or that the DNA of birds was more similar to that of worms than to that of cats, or that animals changed rapidly without selection, the impact on current ideas in evolutionary mechanisms could be fatal.
Even though science and religion are in basic conflict, one should be cautious in assuming either a radical decline of religious belief in recent years or that any decline is due to science. Many scientists, around 50 per cent, are religious, and in the United States more than 90 per cent of the population admit to religious beliefs. Moreover, the social historian David Martin has pointed out that it is necessary to examine more than just the figures for church attendance: superstition is still strongly with us. To quote Martin on secularization in the so-called age of science:
Far from being secular our culture wobbles from being a partially absorbed Christianity, biased towards comfort and the need for confidence, to belief in fate, luck and moral governance incongruously joined together. If we add to these layers of folk religiosity the attraction of Freudianism and Marxist mechanics for segments of the intelligentsia, it is clear that whatever the difficulties of institutional religion they have little connection with any atrophy of the capacity for belief.
In his view, vast numbers of people work on two basic principles: one is the rule of chance – fate – the other is a moral balance in which wicked deeds are punished. I believe that many of us continue to subscribe to this magical, more natural, image of the world.