Adventure

Introduction

Tae Dynamic or SCIENCE .

ALEXANDER S. RussExt, M.C., M.A., D.Sc.; University Lecturer in Inorganic Chemistry, Oxford; Student and Tutor in Natural Science, Christ Church, Oxford.

II Bryonp KNOWLEDGE

JoHn Macmurray, M.C., M.A., Fellow, Tete and Bae Lecturer in Philosophy, Balliol College, Oxford.

Ill

Moran ADVENTURE

I. In Search of a Morality.

II. Code and Experiment.

III. The Ethics of Sex.

Burnett H. Streeter, M.A., D.D., F.B.A.; University Reader in Christian Origins, Oxford; Fellow of the Queen’s College, Oxford; Canon of Hereford,

IV

FrInaity IN RELIGION Burnett H. STREETER.

PAGE vi ADVENTURE V

OBJECTIVITY IN RELIGION JoHN MAcMURRAY.

VI Myta anp REALITY

CatTHERINE M. Curtcorr, M.A.; Fellow and Tutor in Classics, Lady Margaret Hall, Oxford.

Index

PAGE

INTRODUCTION

Tuts book is not a collection of detached essays ; it is the outcome of a continued effort at corporate thinking on the nature of Science and Religion, and on their relation to one another. It is in one sense a sequel to my book Reality, in another it is a resumption, after a long break, of the series of books, Concerning Prayer, Immortality and The Spirit. Like these it arose out of the meetings for discussion that took place at the house of Miss Lily Dougall at Cumnor. By the deaths, within six months of one another, of Arthur Clutton-Brock, Cyril Emmet and Miss Dougall herself, the old “ Cumnor Group ’ was shattered. But it was Miss Dougall’s wish that her house, Cutts End, should continue to be, in her own phrase, ‘a workshop for religious thinking’; and her old friend, Miss M. S. Earp, has carried on the tradition.

Beginning in March 1924 there were arranged, at varying intervals, a number of week-end conferences of from six to eight members, made up mainly of scientists and philosophers of the post-war generation in Oxford. The discussions at these informal gatherings were greatly enriched by the presence, at one time or another, of as many as ten persons who are not contributors to this volume—including some who would dissent from certain vii vill ADVENTURE of its main positions. Among those whose contribution was felt to be of special value we should wish more particularly to name Dr. J. A. Hadfield, Prof. Julian Huxley (then Fellow of New College) and Prof. H. J. Paton of Glasgow (then Fellow of the Queen’s College).

These conferences were held without any idea of — their leading to the production of a book; they aimed merely at an interchange of views and clarification of issues. But after one that took place in October 1925 it seemed to me that among the papers which had been contributed were some which, from very different starting - points, were converging towards a new and fertile conception—or at least towards a new angle of approach to certain of the more fundamental questions involved in the relation of Science and Religion. This book has grown out of these papers—supplemented by one which approaches the problem of Morals, as that presents itself to the present age, from the same standpoint. Each essay represents in the last resort the individual view of its writer; but they have been rediscussed and subjected to further criticism at three more meetings at Cutts End, attended only by the writers and Miss EHarp—as a result of which each has been at least once remodelled or rewritten.

The unifying idea which underlies all the essays is that indicated in the title of the book—the idea of ‘adventure’. The present century has witnessed a very considerable change in the point of view of thinkers in regard to Science, Morals and Religion; and in different ways the dynamic and adventurous quality in these has become more evident than it was to earlier a

INTRODUCTION migdia > workers. Some of the implications of this change, in its bearing on the relations of Science and Religion, I endeavoured to bring out in my book Reality, a few chapters of which had in draft form been read as papers, and usefully criticised, at some of the earlier conferences. Certain further implications are worked out in the present volume. The value of what we have written must be judged by others; but to us it seems that, unless our line of thought is fundamentally mistaken, the period when the ‘ reconciliation ’ of Science and Religion was something which men could regard, according to their temperaments, as a matter either for hope or for despair, is passing away—to be succeeded by a period in which they will be regarded as two diverse, but intrinsically connected, adventures of the spirit of man.

B. H. STREETER.

BY

ALEXANDER SMITH RUSSELL, M.C., M.A., D8e.,

UNIVERSITY LECTURER IN INORGANIC CHEMISTRY, OXFORD, STUDENT AND TUTOR IN NATURAL SCIENCE, CHRIST CHURCH, OXFORD

. s

SYNOPSIS

Tue Am or ScreNcE

Science attempts to describe the phenomena of the external world and in the widest sense to understand it. Empirical evidence is the only test of validity which it accepts. In investigation it demands freedom of opinion and of action. It is continuous: it takes over, and builds up from, all that is best in past work. The scientist’s work is much more impersonal than the art of the artist or the philosophy of the philosopher.

Tue Reawity or ScreNcE

The reality of the scientist embraces two classes of concepts: (a) those directly observed by the senses, and (b) those inferred from them by analogy. The attitudes of the more sanguine and imaginative, and of the more critical, types of investigators contrasted. While workers of the latter type make their contribution, it is those of the former who make the great discoveries. Hypothetical waves in a hypothetical ether have led to the broadcast service of the present day.

The scientist as an investigator is not concerned with the ultimate questions of philosophy, largely because he is absorbed in his own work. He takes the world pretty much as he finds it.

HyYPoTHESES AND Laws

He obtains knowledge of the external world by carrying out experiments, framing hypotheses to explain the results of the experiments, testing the hypotheses by further experiments, and so on. Neither hypotheses nor the widely verified hypotheses called laws are invested with the character of finality ; they are subjected to never-ceasing criticism in the hope that through modification they will attain nearer to the ideal of truth.

Nature is continually being shown by the experimentalists to be more remarkable than has ever been imagined. Every new discovery contains something completely unexpected. The discoveries of the elements selenium and radium are quoted in illustration of this.

Tur AssUMPTIONS IN EXPERIMENT

Three assumptions are customarily made when experiments are carried out: (1) that there is a reign of law, (2) that the working of the whole is deducible from an investigation of the smallest parts, (3) that the simplest interpretation of experimental facts is likely to be the nearest to the truth. The second and third of these are illustrated by examples from contemporary science. There are cases of alternative hypotheses, however, where the ultimate victory of one appears to be impossible. In such cases a completely new theory is necessary and seen like genius is required to formulate it.

ADVENTURE IN SCIENCE

Science at the present moment is getting away from the intellectual pharisaism of recent years and becoming adventurous ; and it is finding it good to be adventurous,

I THE DYNAMIC OF SCIENCE

Tue Aim oF SCIENCE

THE aim of Natural Science is to describe the phenomena of the external world, and in the wide sense to understand it. In its most developed form science presents certain characteristic features: it is a progressively increasing body of knowledge concerning the external world ; it deals with judgements for which unanimous assent may be obtained from qualified students of the subject concerned ; it demands and accepts as the only test of validity empirical evidence; it makes its first appeal to those who are interested in truth for its own sake rather than to those who see in the applications of scientific knowledge a source of power over material things. .

Science is a living body characterised by freedom, continuity and a spirit of adventure. It demands freedom of action and of opinion, freedom to make inquiry and experiment as it wills, and to draw the proper, as opposed to convenient or prejudged, conclusions from the results of those inquiries. It happens at the present time to be allowed this freedom of inquiry only in those fields where the results do not engage our passions ; in inanimate nature, for example. There men can be sufficiently detached to seek truth for its own sake. 4

I THE DYNAMIC OF SCIENCE 5

This freedom is fettered when science seeks to extend itself in such fields of study as biology, economics or sociology—for obvious reasons. In these subjects not only are experiments much harder to carry out than with inanimate bodies, but public opinion would be slow in tolerating changes or restrictions in its thoughts and habits which the results of such experiments might demand.

Science is also continuous. It takes over, and builds up from, all that is best in the past ; the advance towards new ideas and knowledge comes from experiments sug- . gested by the old, which may be rejected @n toto or (more usually) retained with modification. Thus, in Chemistry, the old idea of phlogiston, a mysterious fluid that emanated from a metal when burnt in air, was rejected as soon as it was demonstrated on a balance that the metal was lighter, not heavier, than the compound which arose when it was burnt. On the other hand, the atomic theory of the constitution of matter put forward in antiquity and revived in a more scientific form by Dalton about 1804—more than a hundred years before the atom itself was actually isolated—has braved all the criticism of nineteenth-century physics and has been extended without essential modification by work done in this century.

Another characteristic of scientific investigation is, or ideally should be, its impersonality. An individual actually makes the discovery, and in the process of investigation he can exercise his personality to some extent. His brains, his initiative and his other personal qualities lead him to discoveries; but the discoveries themselves do not bear the impress of his personality. They are impersonal. The discoverer is generally one of many co-operators, no one of whom is necessarily

6 ADVENTURE as 1 essential to the achievement of the results obtained. Even such a marvellous advance as the theory of Natural Selection was made independently by two such different personalities as Russel Wallace and Darwin. At any rate, scientific knowledge bears the imprint of its discoverer altogether in a smaller degree than does the art of an artist or the philosophy of a philosopher.

Tue Reatity oF SCIENCE

The reality of the scientist embraces two broad classes of concepts. First, those things, such as ourselves, the stars, the table and so on, which are ordinarily described as being directly observed by the senses, the reality of which is accepted uncritically by common sense. Secondly, hypothetical entities like atoms, electrons, wireless waves and the ether, which cannot be directly observed. These hypothetical entities are regarded as real, firstly, if an analogy can be found to make them correspond with things which are judged to be real, and, secondly, if they give a satisfactory account of the experimental facts for the explanation of which they have been invoked. Atoms, for example, are regarded as real because they are comparable with such simple objects as small elastic balls of steel or of rubber, electrons because they are comparable with electrically charged balls, wireless waves because they correspond in some respects with the familiar waves of the sea. Anything may be temporarily included in the second class, provided an analogy for it can be found, and provided also that the concept works in practice ; it is obvious, therefore, that the second class may become a very wide one.

In the mind of the scientist, as I have said, there is

1 Cf. N. R. Campbell, Physics: The Elements, p. 244.

: THE DYNAMIC OF SCIENCE ay no doubt about the reality of the first class of concepts, but acceptance of the second class is clearly a matter of faith, and it is wider in the mind of the more trusting and sanguine than in that of the more rational investigator. The latter performs the useful but often unpopular duty of criticising and even pooh-poohing many of the ideas and analogies of the former. One of his functions is to relegate to a third class—the class of the discredited—concepts which too easily had been admitted into the second. As the history of science has shown, however, his usefulness has been more conspicuous in critical than in creative work. The sanguine investigator invents a new concept; the rationalist attempts to destroy it by the argument from incredibility ; the former replies that the latter’s criticism, even his constructive criticism, could not have existed had not something been put forward to be criticised. He invites the rationalist to explain why the alleged fictions frequently lead to correct results. And indeed it is a matter of history that as experimental facts accumulate and clear the path of obstacles, many entities in the second class of reality approximate more and more in prestige to those of the first; the faith of the more sanguine scientist becomes justified. Wireless waves were originally hypothetical waves in a hypothetical ether; they are still hypothetical waves in a hypothetical ether, but any one at the present time who doubted their reality would be regarded as a crank. In the second half of the nineteenth century the more optimistic and imaginative investigators of physics and chemical science beat the more rationally minded all along the line. It was they who made the big discoveries. A desire for symmetry in writing down differential equations in connection with his electromagnetic theory of light is said to have led Clerk Maxwell to postulate unknown, and till then unimagined, ether disturbances. Many years later it was shown by the experimentalist, Hertz, how such disturbances could be produced. Later work by Lodge, Marconi and others, revealed the wonderful properties of these waves ; and adaptation to practical needs has given to all but the poorest the broadcast service of the present time.

The scientist may be fairly described as an eager, simple-minded and single-minded seeker after truth. He does not profess to be on the road to discover all truth, but only such truth about the external world as is amenable to classification and capable of description in laws and theories which can be tested by the experimental method.

What may be called the ultimate questions of philosophy do not concern the scientist gua scientist. For example, the existence of the external world or the ultimate nature of its reality are not for him vital questions. He would probably say that they do not matter, or that he is too busy with what engages him to give these questions the thought they require. He would allow that there are other subjects of study besides those which occupy the scientist, and other methods of investigation besides the experimental method or its equivalent, but they are for others. For him it is enough that the external world is an obvious field of inquiry for his talents. The study of its phenomena is of sufficient interest, and, as he thinks, importance, to provide him with a useful lifework. The apparent existence of other conscious beings who share with him many of his experiences is regarded as an adequate motive for belief in this external world. They agree with him that unsupported bodies fall to the ground, that summer is hotter than winter, that oxygen ey oan is necessary for life, and so on. Even if the external world is a hallucination, it would not matter to the scientist so long as his fellow-investigators shared the hallucination undistorted with him.»

HYPoTHESES AND Laws

How does the scientist strive to attain knowledge of the external world? He first selects a particular field of study and makes himself acquainted with the main body of existing knowledge, and with the technique developed in it. He may discover gaps in this knowledge, or he may be critical of some of it. Implications are seen which must be put to the crucial test ; and his first constructive work is in devising and carrying out experiments to test the points he hasin mind. From the results of these experiments, directly or through their implications, he makes inferences ; and this he must do very carefully, with, almost low cunning in fact, for whereas there is little doubt that Nature answers: properly the questions put to her, there is often doubt whether the question as put by the experimenter is what he actually intended. On the results of experiment he frames a hypothesis—if he can—a plausible conjecture as to the explanation of what has occurred, to be retained or rejected on the results of the further experiments which it suggests. If the hypothesis cannot stand subsequent experimental examination, it is modified or rejected ; if it can, it is often called a Law. A Law, then, is a generalisation from observed facts possessing greater probability than a hypothesis; it is a hypothesis which has been widely verified. Thus law differs from hypothesis in degree only. Laws like Newton’s laws of motion or Einstein’s law of gravitation are singularly exact and of almost universal application.

10 | ADVENTURE —-- F

(It is possible they do not apply in the little world-initself within the atom.) Others, like Boyle’s law (connecting the pressure and the volume of a gas), are less exact, being true only within a narrow range or under qualification. Despite their prestige, laws, like hypotheses, must be modified or even superseded if fresh experimental evidence demands it. This is one of the greatest points of interest in science.

The personality of the propounder or the methods, other than the experimental methods, by which he arrived at his law or hypothesis are of little importance. Laws have been arrived at by conscious reasoning from discovered facts; they have arisen from intuition or been suggested by chance remarks, or even by the. . mistaken arguments of other workers; at times, oddly enough, they have been put forward out of perversity in Opposition to a supposedly well-established law. The important thing is, not who made the discovery or how the hypothesis was called into being, but whether it will stand the test of all the experiments which it suggests, or will explain facts hitherto unexplained. If it cannot, it should be dropped; but if partly or wholly it can, the whole existing body of knowledge must make a place for it, and must, if necessary, allow itself to be modified to the proper extent.

The impact of new facts upon the old knowledge is often of quite an unexpected and even unexpectable kind; and it is this unexpectedness which stimulates workers to go forward by experiment and observation to fuller knowledge and to more satisfactory hypotheses. Facts are the unsettling things. Nature is continually being shown by the experimentalists to be more remarkable than the wildest surmises of the most enthusiastic theorisers. Our imaginations are still so narrow that,

I THE DYNAMIC OF SCIENCE 11 when new knowledge is revealed by the experimental method, we are inclined to be incredulous. The news has to be forced on us. In some cases the newer hypotheses and laws appear so strange that they have not been universally accepted till the older generation, which rejected them, has died out. For example, Faraday never fully accepted the atomic theory of matter, and Kelvin’s attitude to much of the best-established work in the early part of this century might be described as ‘die-hard’. However prescient the scientist imagines himself to be, every new discovery contains more than its discoverer had guessed. For example, chemical theory, before the discovery of the element selenium, was so far advanced that the properties of this element were confidently predicted. These predictions were exactly verified when the element was discovered ; but it was then found that, in addition to these predicted properties, selenium had a new property which could not have been predicted—of conducting the electric current much better in the presence of light than in the dark. This has led to the discovery of other bodies which possess this property in a higher degree, and these are the basis of such inventions as transmit photographs by telegraphy, or make possible the ‘phonofilm’ in which the speech of the film actor is exactly ayidlnon: ised with his movements. Selenium is not an isolated instance. All the properties of the element radium (and other radioactive elements) could have been predicted, except their radioactivity now seen to be the most important property of all. The study of radioactivity, a property of matter unimagined before its discovery, has contributed more than any other study to our present knowledge of atomic structure.

THE ASSUMPTIONS IN EXPERIMENT

In the attempt to discover truth by the experimental method there are three main assumptions customarily made: (1) that there is a reign of law, (2) that the working of the whole is deducible from an investigation of the smallest parts which are amenable directly or indirectly to observation, and (3) that the simplest interpretation of experimental facts is not merely the most useful one for the development of knowledge, but, in so far as human beings can arrive at truth, the nearest to the truth. The scientist’s justification for adopting these is that he has found them very convenient and useful in practice. If any one can suggest something better, he would say, he would be willing to adopt the suggestion provided that investigation by the experimental method proved it better.

(1) The first of these assumptions requires little discussion. It was made by the earliest scientists and has never been seriously opposed. It is a necessary assumption because, if there is no reign of law, there can be no science. Mysterious happenings of whatever nature are not regarded as being outside the reign of law ; they are regarded as interesting phenomena which require investigation. When they do not yield to investigation, it is not concluded that they are irreducible to law ; it is merely assumed that the laws which govern them have not been found. As it is theoretically possible that certain phenomena may never be explained as conforming to law of some kind, it is unwise of the scientist to assert that they will. Nevertheless, he will never renounce the attempt to bring everything under law, and, indeed, under the smallest possible number of laws. The scientist does find, however, that certain re

: HE DYNAMIC OF SCIENCE 13 types of phenomena are more easily reducible to law than others; and naturally he studies these first. He has a certain right to decline to study phenomena not obviously reducible to law until he has finished studying those that are. Thus the properties of electricity, the expansion of gases, the movements of the heavenly bodies, are more obvious studies than the vagaries of the climate, or the migratory habits of birds ; while the two last are obviously questions more suitable for investigation than the connection between red hair and quick temper, or between strangeness of surnames and excellence in poetic achievement.

(2) The macroscopic, or large-scale method of investigation, is that of the child. To a child a ship, a long distance off, seems merely a toy ship on a large scale, a solid piece of wood with mast and funnels stuck into it. The scientist, on the other hand, insists on investigating at the closest possible range—arguing that only by such an investigation is there any hope of finding out what makes the ship go. Nothing is too trifling ; everything must be observed. The knowledge so obtained illuminates, although not always obviously, all that can be known on the larger scale; but the converse is not equally true. The appearance of a piece of metal does not suggest to any one the atoms and electrons of which it is said to be composed; but the atoms and electrons tell us all that is important about the metal. The lustre and strength of a metal, its power of conducting heat and electricity, are all known to be due to the presence in it of free electrons. Given the free electrons, the rest follows. On the other hand, a substance like chalk is known to be composed of atoms with ‘bound electrons. It has, therefore, little strength and no metallic lustre ; it insulates from heat and is a nonconductor of electricity. The large-scale method reveals, no doubt, a great number of interesting things, but it is the small-scale method which initiates most of the real discoveries. It is both interesting and useful to know at what. time of the year roses bloom best, or the exact percentage of Englishmen who are over six feet in height, or that if iron be coated with paint it will not rust so long as the paint remains intact. Knowledge of this kind may lead to power or control over natural forces, but not to anything like the same degree as does the small-scale method of investigation; it is a mere preliminary to small-scale investigation.

The difference between the values of the small-scale and large-scale points of view in practice may be illustrated by the methods in current use for preventing the rusting of iron. It is obvious that if iron be coated with something like paint or pitch which is not easily weathered, and which at the same time shuts out moisture from the surface of the iron, fusting will be avoided. A method of the same type, but of higher value, is to plate the iron with a metal, like nickel or silver, which is not tarnished in the air. These preventives, although ingenious and useful, may be for many purposes cumbersome, and they are superficial ; they do not go to the root of the matter. An intensive study of the structure of the atom has outlined a way of keeping iron from rusting without the external application of other material. It shows that iron and a few other metals may exist in two distinct forms— one the familiar form which is liable to rust, and the other, harder to prepare and less stable, which resembles the noble metals gold and platinum in resisting corrosion or tarnishing. With this possibility before him, the experimenter was spurred on to discover the conditions as necessary for the preparation and preservation of this untarnishable form, and this, aided by a series of happy accidents, he has now accomplished. The practical result is ‘ stainless ’ steel and iron.

(3) The third assumption, that the simplest interpretation of experimental facts is not merely the most useful but probably the truest, seems to bring in the personal predilections of the experimenter. The facts obtained by experiment are, or at least should be, independent of the person by whom they were discovered, and of time and place. Work done in England should be capable of exact repetition in Japan and should lead to the same results, provided only that the workers are thoroughly competent. A scientific fact, indeed, would not be regarded as a fact unless unanimous assent were obtained for it from informed students of the branch of science to which it belonged. It is never necessary, indeed it would be impossible, that the fact should be experimentally verified by every one before he accepted it. The possibility of such verification by all, and the actual verification by a trustworthy few, is sufficient for the acceptance of a fact. Interpretations, however, may be different, because interpretation is something individual and personal, depending on the qualities of a person’s mind. One man tends to choose what seems to him the simplest interpretation, another the first interpretation that occurs to him, a third a highly complex one on the ground that the simple interpretation of anything has never proved to be the right one in the end, and soon. Itis clear that, before we are asked to decide between the interpretations put up for choice, they should be rigorously examined by the experimental method. This examination has often a remarkable effect both on the number and on the character of these interpretations.

Ambiguities of interpretation, however, cannot always be dispelled by experiment. In such cases it is considered best to choose the simpler of alternative hypotheses. This, however, is not wholly a matter of taste or of convention ; it is really an attempt to get away from what is merely pragmatic and reach something which is objectively true. Anything might be explained, anyhow, if hypotheses were allowed to be invented at will; the fewer the assumptions involved in the theories or hypotheses, the further we get away from ‘clever’ proofs (like those which seek to show that Bacon wrote Shakespeare’s plays or that Queen Victoria wrote ‘In Memoriam’), and the more confident we are that we are not merely making ingenious guesses. A ‘simple’ theory need not be simple in form. A theory is said to be ‘ simple ’ when it is based on the minimum discoverable scientific postulates. Einstein’s theory of gravitation is more comprehensive than Newton’s in that it explains the advance of the perihelion of Mercury, the deflection of rays of light in the neighbourhood of the sun, and the displacement, towards the red end of the spectrum, of light emitted by the sun ; it is also actually simpler than Newton’s theory. It is therefore accepted as truer even though it is much harder to understand, Again, whether the earth goes round the sun or the sun round the earth, has not yet been decided by experiment. The Ptolemaic view that the sun went round the earth was adopted because it was the simplest interpretation of what then seemed obvious. The Copernican view, that the earth goes round the sun, supplanted the earlier one, not on any direct experimental evidence, but because the interpretation of the motions of the heavenly bodies was on this view far simpler than on the Ptolemaic. It was thought until recently that the te: i 4 = gaol alls