ta of % terstt of IE. I.E. SMITH AN INTRODUCTION TO A BIOLOGY AND OTHER PAPERS AN INTRODUCTION TO A BIOLOGY AND OTHER PAPERS AL Df DARBISHIRE Author of " Breediiy and the Mendelian Discovery This " Worke, although it may not so compleatly answer thy curious expect, yet let it suffice I have performed my best." From the prefatory letter to the reader in "An Enucleaire, or Alphabet of Verbes, Neuters, Common and deponents, profitable and necessary to all students of humanitie. Likewise for parsing an helpe extraordinary. Collected and composed by Wl DARBISHIRE, Philosopher, London, 1624." 520950 CASSELL AND COMPANY, LTD London, New York, Toronto and Melbourne 1917 CONTENTS PAGE AN INTRODUCTION TO A BIOLOGY . . , . 1 APPENDIX TO AN INTRODUCTION TO A BIOLOGY: 1. MENDELIAN PRACTICE IN THE LIGHT OJF BERGSON'S BIOLOGY . . . . • . 90 2. NOTES OF A LECTURE GIVEN IN JULY, 1914, AT THE GRADUATE SCHOOL or AGRICUL- TURE, HELD AT THE UNIVERSITY OF MlS- SOURI, COLUMBIA, MISSOURI . . . 100 3. CORRESPONDENCE WITH M. BERGSON . . 103 4. NOTES AND EXTRACTS . . . . 104 ON THE BEARING OF MENDELIAN PRINCIPLES OF HEREDITY ON CURRENT THEORIES OF THE ORIGIN OF SPECIES . ... . . . . . 127 ON THE SUPPOSED ANTAGONISM OF MENDELIAN TO BIOMETRIC THEORIES OF HEREDITY . . . 144 THE LAYING BARE OF THE MARVEL — A LEGEND . 162 ON THE DIFFERENCE BETWEEN PHYSIOLOGICAL AND STATISTICAL LAWS OF HEREDITY . . . 167 RECENT ADVANCES IN ANIMAL BREEDING AND THEIR BEARING ON OUR KNOWLEDGE OF HEREDITY 207 vi Contents PAGE SOME TABLES FOR ILLUSTRATING STATISTICAL COR- RELATION 219 SOME CONDITIONS OP PROGRESS IN BIOLOGICAL INQUIRY 239 MENDELISM >. 261 FRANCIS GALTON ... 281 PREFACE ARTHUR DUKINFIELD DARBISHIRE, son of Samuel Dukinfield Darbishire, M.D. Oxon., was born in 1879, and educated at Magdalen College School and at Balliol College, Oxford. He worked under Pro- fessor Weldon for the Honour School of Zoology, and was placed in the Second Class in 1901. In October of the same year he was appointed Demon- strator in Comparative Anatomy at the University. His interest in the problems of heredity was already beginning to absorb him. At the instigation of Professor Weldon, the leader of the Biometric school at Oxford, he began a series of breeding experiments with mice, the results of which were published in BiometriJca.1 He had a profound admiration for Professor Weldon, and was, not unnaturally, influenced at this time by his hostile attitude towards the Mendelian School. But when he moved to Manchester, where he filled the post of Demonstrator in Zoology at the Uni- versity from 1902 to 1905, he began to think out on his own lines the problems raised by the Mendel ian discovery. Continuing his experiments with mice, he set himself to examine the truth of 1 ** On the result of crossing Japanese Waltzing Mice with European Albino Races." Biometrika. Vol. II., No. 1, Nov. 1902 ; Second Report, Vol. II., No. 2, Feb. 1903 ; Third Report, Vol. II., Part III., June, 1903; Final Summary, Vol. III., No. 1, Jan. 1904. Vlll Preface the position from which he had started upon them. He had begun as a pupil of the Biometric school with a strong bias against the Mendelian theory. He now worked his way, through difficulty and depression, to a point from which he saw that the contradiction between the two theories was only apparent and was really due to a difference in the point of view from which each party approached the same facts. He defined his position, and cut himself adrift from both schools in his contribution to the debate on heredity at the meeting of the British Association at Cambridge in 1904,1 and in two papers contributed to the Manchester Literary and Philosophical Society, " On the Supposed An- tagonism of Mendelian to Biometric Theories of Heredity " (1905) and " On the Difference between Physiological and Statistical Laws of Heredity " (1906). 2 He maintained this independent and critical attitude all his life, and upon no man's work, whether of description or interpretation, did he keep a closer critical watch than upon his own. " One's attitude as an investigator," he wrote, " should be one of continual, unceasing and active distrust of oneself." His later experiments with mice, peas, fowls and rabbits were designed to test the Mendelian hypothesis with absolutely no pre- judgment of the case. After thirteen years of patient investigation he could write in February, 1915, "I consider the Mendelian principles to be still sub judice ; and they are so attractive by reason of their simplicity that they need to be under a very 1 Vide infra, p. 162. * Vide infra, pp. 144 and 167. Preface IX stern judge." His book, " Breeding and the Men- delian Discovery," published in 1911, is a clear summary of his work and thought on the prob- lems he had himself investigated. From 1905 to 1911 he held the post of Senior Demonstrator and Lecturer in Zoology at the Koyal College of Science. It was at this period that he came in contact with Samuel Butler, first through " Ere- whon," then through " Life and Habit," and his conception of evolution underwent a profound change. In his lectures thenceforward he, traced the growth of the theory from the Greek philo- sophers through Buffon and Lamarck up to Darwin, and the philosophical bearings of the theory became for him its paramount interest. In 1911 he accepted the newly created post of Lecturer in Genetics at the University of Edinburgh. The University Experimental Farm at Fairslacks under the Pentland hills gave him a new field for his investigations in heredity. His friendly asso- ciation with Professor Cossar Ewart helped to make this post the happiest he had held. He had already become deeply interested by Bergson's thought when Bergson himself came to Edinburgh to give the Gifford lectures in the summer of 1914. He met and talked with Bergson, had the pleasure of introducing him to Butler's theories, and the rare experience of talking about his own speculations to a thinker who saw their drift and value. At the opening of the war in July, 1914, he was in America, lecturing to the Graduate School of Agriculture at the University of Missouri, Columbia, Missouri. As a result of his lectures the University x Preface immediately offered him a Research Professorship at Columbia. He was also offered the Professor- ship of Zoology at the new University of Vancouver. But he could not reconcile himself to leave England after the outbreak of war. Owing to physical delicacy he was at first pronounced unfit for the Army, and he trained himself for munitions work at the Heriot Watt Engineering College. But he found difficulty in getting suitable employment, and in July, 1915, he tried his luck at a recruiting office and was enrolled as a private in the 14th Argyll and Sutherland Highlanders. He devoted himself to his duties as a soldier with the same zest and the same meticulous attention to detail that marked his work in other spheres, and he won the love and admiration of his comrades. On Christmas Day, in camp at Gailes, he was taken suddenly ill with cerebral meningitis, and he died next morning. Three days after his death he was gazetted Second Lieutenant in the Royal Garrison Artillery. As a man of science he was perhaps unusual in combining a devotion to pure research (he would have laughed at the phrase, but all his colleagues applied it to him) with a freely speculative interest in his subject. He carried on his investigations with an untiring patience, watchful in self-criticism, re- cording his results with the greatest care and thorough- ness, and persistently postponing interpretation until he had gathered more results. According to his principle, he maintained an absolutely dispassion- ate attitude as scientific investigator. Those who knew him only in other spheres would not easily Preface XI believe that he could be dispassionate about anything. His interest in the philosophical basis of his subject was balanced by a close and intimate knowledge of its practical side. He hated and suspected all mutual exclusions, sharp antagonisms, supposed contradictions. Theory and practice were to him as closely connected as good with bad or science with art. He believed there was no such thing as the purely philosophical or purely scientific or purely practical sphere in his subject. He had a passion for gardening and for farming ; he liked to be at work in the soil with the hoe or dung-fork, or amongst the animals on a farm. His thorough knowledge of horticultural processes, which contributed so much to the success of his scientific experiments, was due to his own experience in all the arts of the practical gardener. Digging was an art which he carried to perfection after years of practice. His delight in doing things as well as they could be done gave him unusual powers as a teacher. He took an unconcealed pride in his skill in dis- section and in elaborate draughtsmanship. In the laboratory he was always working and learning, and his idea of teaching was not to give information (he often refused it), but to show people how to find out things for themselves. As a lecturer his best qualification was his absorbing interest in the things he had to say. His mind was never more clear, alert, and alive than when he talked to intelligent listeners. He had the instincts of an actor and a good deal of the art ; and he could get in touch with his audience at once. Xll Preface The three greatest influences over his mind and thought were Beethoven, Samuel Butler, and Berg- son. They had in common two things that he could not do without : humour, and the sense that the source of life is spirit. Their influence was the quickening influence of one personality on another, and they were a constant stimulus to him in his later speculations, which became increasingly meta- physical in character. He chafed against the ortho- doxy of science, and his cherished desire was to make a contribution towards biology in the strict meaning of the term. The whole field of life should be its sphere, he thought ; its basis should be philo- sophical and its method dispassionately critical ; and finally, the spirit in which the biologist ap- proaches his subject should be the same spirit of intense interest combined with humility, with which a lover of music hears a symphony of Beethoven, or a lover of life meets one of the transcendent experiences of life itself. In character he was essentially childlike ; gener- ous to a fault, with no arrogance, no malice and no meanness. He had a genius for absurdity, and he used it, as he used his other gifts, with the delight of a child and the skill and thoroughness of an artist. He never made enemies, and he had an infinite capacity for making friends. The men who helped him with his experiments, his laboratory assistants, his gardener, the farmer at Fairslacks were all to him fellow- workers and friends, to whom he delighted to express his gratitude, and with whom he shared, as far as he could, his jests, his interests, and his ideas. Preface Xlll All who knew him will keep in memory a person- ality alive and young to a rare degree, fulfilling itself in a passion for music, much laughter, a per- fectly disinterested love of truth, a delight in pro- ducing delight in others, and the keenest possible interest in life itself whichever way it led him. During the spring and early summer of 1915 my brother was at work upon a book for publica- tion by Messrs. Cassell in the autumn. In May he writes to M. Bergson, " I am hard at work on my book about evolution. I think I am going to call it ' An Introduction to Biology ' — Biology as I think it ought to be, not Biology as it is. For the problem of evolution is merely a department of the problem of life, it appears to me. I am convinced that the theory of natural selection is in no sense an explanation of evolution." The plan of the book is sketched in a prospectus written for the Publishers in June, 1915. " AN INTRODUCTION TO A BIOLOGY " This book is addressed to all those who are curious about the meaning of life, and is an attempt to put before them the essence of the current mechanistic explanation of the organism and mate- rialistic explanation of the universe, in order that they may examine for themselves these accepted scientific explanations of life. The author does not pretend to set forth a series of conclusions led up to by the stages of a logical argument which follow inevitably and relentlessly from^one another, and xiv Preface which compel the reader to reach those conclusions and no other. The reader is not offered a set of irrefragable laws which he must believe, but certain preliminary considerations which, in the opinion of the author, effect a clearing of the ground upon which the foundations of a biology may some day be laid. " The term Biology is used by the author to signify the interpretation rather than the mere description of life. The Biology, therefore, in the interpretative sense, put before the reader is not a nearly complete fabric the main constructional lines of which have been laid down once and for all, and the completion of which will consist in the filling in of detail ; but a tentative indication of the direction in which some approximation to an understanding of life may be sought. " The main constructive thesis of the book is the idea, which we owe to Samuel Butler, that the details of the process of evolution can be studied most minutely in man, in whose extra -corporeal organs, his weapons, implements, and machinery, evolution is proceeding with great rapidity. " This study of the evolution of human detach- able implements leads on to M. Bergson's thesis that the human intelligence owes its essential traits to the fact that it was developed pari passu with the acquisition by man of his control over matter. Upon this conception of the human intelligence rests the main critical thesis of the book, which is the attempt to show that natural selection was acceptable as an explanation of evolution, because it was an explanation in terms of matter, and Preface xv because it involved the idea that the organism is no more than a machine." The book was to consist of four long chapters, the contents of which were to be as follows : I. — The failure of modern interpretative Biology. II. — The utilitarian origin of the human intelligence. III. — The consequent acceptability to many minds of a mechanistic theory of the organism and of a materialistic theory of evolution. IV. — Some suggestions as to the direction in which an understanding of life may be sought. When he joined the Army two chapters were written, the first revised, the third begun. The fourth chapter, which was to have been the constructive part of the book, is entirely unwritten. In his pocket-book he sketches the plan of the four chapters characteristically in the form of a Beethoven symphony : CHAPTER I. — 1st Movement. CHAPTER II. — Scherzo. CHAPTER III. — Adagio. CHAPTER IV. — Finale. Amongst his papers the only direct indications I can trace of the contents of the final chapter are XVI Preface in a note to Professor Dendy, and a letter to Mr. Charles Douglas. The first, dated June 17, 1915, is a request for a Table at the Marine Biological Laboratory at Plymouth for August. " I wish," he writes, " to make one or two drawings and some observations on the habits of Carcinus maenas for the purpose of my new book appearing in the autumn." I imagine that he intended to support his general belief in the part obscurely played in evolution by the will and intelligence of living things, with re- cords drawn from a close and intimate study of the habits of a particular animal. The second is a description of a paper which he sent to Mr. Douglas, March 10, 1915, with a view to its publication in the " Transactions of the Highland and Agricultural Society." " The greater part of it," he writes, " is a lecture which I gave to a com- bined meeting of the Scientific and Agricultural Societies in the University of Aberdeen. It con- tains in crude form ideas which I hope to express better in about two chapters of a book I hope to have ready by September." The extract in question is printed (vide infra, p. 90) in an Appendix immediately after the un- finished fragment of " An Introduction to a Biology," and I have added to it some notes of a lecture de- livered in June, 1915, which illustrate in a technical way one important point raised in the extract. I had also intended to include in this Appendix a letter to M. Bergson, and a reply from him of December, 1912, which touch upon the intended subject-matter of the book. My brother's letter is Preface XVll not to be found, but M. Bergson has most kindly allowed me to print his reply, which suggests its contents. For the rest, to attempt even an outline of the concluding chapter which my brother left unwritten would be manifestly useless. I have thought that the best thing I could do was to gather together those of his papers, whether published or unpublished, which throw light on his thought and explain his point of view. In the Collection of Notes and Extracts (vide p. 104) I have put first in order those notes which were made whilst the book was in progress and which have a direct bearing upon it. The scien- tific papers are arranged chronologically. As a record of his thought the whole is in one way ab- surdly incomplete. For except under compulsion he wrote little. He did his thinking in his head, and his papers and lectures, especially in recent years, were given ex tempore, often without any notes at all. He was always loath to set down conclusions, for his mind was alive and growing, and conclusions were after all, perhaps, what he never hoped to reach. For all its incompleteness, then, this book may give in some degree a true picture of bis mind. I wish to thank the following for their courtesy in allowing me to reprint papers of my brother's : The Editor of Nature, the Editor of The English Review, the publisher of Science Progress, the Editor of The Times Literary Supplement, the Council of the Manchester Literary and Philosophical Society, the Committee of the Manchester University Biological Society, the Editor of the Manchester University XV111 Preface Magazine, the Directors of the Highland and Agricultural Society, The President and Council of the Koyal Horticultural Society. I am exceedingly grateful to Professor Curtis, Professor Keed, and Miss M. L. Keene, of the University of Missouri, for their generous help in placing at my disposal their notes of my brother's lectures delivered at Columbia in 1914. Professor J. A. Thomson, of Aberdeen, has had the kindness to read the proofs of the first part of the book, and I have greatly benefited by his know- ledge and insight in a number of corrections. I owe a special debt to my friend Mr. A. D. Lindsay, of Balliol College, Oxford, for his help and advice throughout the preparation of the book. HELEN DARBISHIRE. BOAR'S HILL, OXFORD August, 1916. TO ROBERT BUCHANAN KING THIS BOOK IS DEDICATED An Introduction to a Biology CHAPTER I " You who speculate on the nature of things, I praise you not for knowing the processes which nature ordinarily effects of her- self, but rejoice if so be that you know the issue of such things as your mind conceives." — LEONARDO DA VINCI. 1. Man is the best starting-point for the study of life. — § 2. Scien- tific investigation is the human activity, the critical study of which is the most urgent. — § 3. Scientific investigation consists of description and interpretation. — § 4. Interpretation. Bio- logical Laws : the urgency of locating them. — § 5. Words : the necessity of keeping a sharp eye on the wanderings of their meanings. — § 6. A glance at our present interpretation of life from the historical quarter.— § 7. On the fitting of theory to the facts of life. THE function of biology, if we adopt the literal, etymological meaning of the word, is to describe and interpret the essential manifestations of life, and to extract from these interpretations a conception, or theory, of life. But the word " biology " has come to be used in certain very much restricted senses, of which it will suffice to mention two. In its commonest signification it merely serves as a convenient common term for the subject matter of both botany and zoology. Another common meaning of it is the study of the An Introduction to a Biology habits of a particular animal or plant. With re- gard to this latter meaning of the word, let it be noted that it applies to the behaviour of any animal except man himself. With regard to the former, the most common meaning of the word, the reader may object that biology, dealing as it does with the comparative anatomy, development, evolution, and many other aspects of animals and plants, so far from dealing with a restricted set of phenomena, ranges over the whole field. There are no other living things than animals and plants ; the study of animals and plants is the province of biology ; there- fore biology covers the whole field of life. The answer to this argument is that the biologist in his efforts to survey the whole field has forgotten one animal, himself. In this way he has committed himself by long habit to the study of those living things of which his knowledge must perforce be external, and has shut himself off from the study of the one living thing which he could know in- timately. He has preferred to " cover the whole field " rather than to dig in the spot where, in my belief, the return for cultivation would have been greatest. The course taken by the biologist may be illustrated by the difference between a recent and an early meaning of the verb " to manure." In one of its original, literal, and etymological significations it meant to work the soil with the hand (that is to say, with the spade, which is an extended, detachable part of the hand) ; but the meaning gradually shifted outwards from the pro- cess itself to the fertilising effect which the process had upon the soil ; and thence it spread to the An Introduction to a Biology other means (besides working with the hand) by which this effect could be produced, namely, the spreading of dung over, and its subsequent incor- poration with, the soil. The biologist has chosen to " cover the field " rather than to dig in that little plot, the study of himself. He has preferred extension to depth, and in so doing he has followed the line of least resistance. Anyone can spread dung ; it takes a man five years to learn to dig well. Man's attention is so accustomed to look outwards, that it is very difficult for him to turn it inwards upon himself. And so the fertile plot has been very much neglected. A variety of circumstances has conspired to exaggerate this extensive character of biological know- ledge to such a pitch that in his anxiety to leave none of the field uncovered the biologist has be- come careless as to whether the covering is thick enough to be of any use. In choosing subjects for investigation he has set more store on the novelty of the result than on the question whether his re- sults will bring us closer to an understanding of life. And the result of this aiming at the target of novelty has often been that he has hit the bull's- eye of triviality. This desire for novelty has become so great that there is a danger of the convention growing up that a particular animal or problem is one man's preserve, to trespass upon which shall be a breach of scientific etiquette. And, as it is, the fact that somebody has worked out the development of a particular animal is regarded as an argument against the selection of that animal as a subject of embryo- 3 An Introduction to a Biology logical research ; but the truth is, surely, that this fact should be an argument for such a selection. For in studying again a development which had recently been studied, the investigator would be throwing light upon two problems instead of only one : upon the meaning of the changes of form undergone by the animal in its development ; and upon the trustworthiness of the human intelligence as an investigating mechanism ; and probably more light upon the second than upon the first. For if the investigator made a point of looking neither at the description made by the previous investigator of the development, nor at his interpretation of the facts of which this description was a record until after he had completed his own description and interpretation, he would obtain results which would be interesting both to the embryologist and to the philosopher. The solitary confinement in their own studies and laboratories, and the complete isola- tion of biological workers all over the world, would doubtless be a hindrance to progress in bio- logical inquiry, at any rate on its applied side ; but it is very doubtful whether the opposite extreme, the perfect means of inter-communication now available, is not an equally serious obstacle to such progress.1 For it ensures the spreading thin rather than the digging deep. It is not, of course, true that the biologist has entirely excluded man from his attention. He has studied him ; but he has done so in the same de- tached, objective way in which he has studied the 1 The probable cessation of communication between the countries now at war may effect a partial removal of this obstacle. 4 An Introduction to a Biology other animals. His knowledge of the form of man is derived from corpses ; and he investigates his performances on the assumption that the human body is a machine. His attention has been con- fined to just those attributes of man which can be studied in the same way as those of non-human animals. This detached, objective method is perhaps the way to establish a science of human physiology and anatomy which shall be useful in the practical science of medicine ; but as long as the biologist persists in studying man in the same impersonal way as that in which he studies the other animals, so long will he shut out of his field of inquiry a whole set of vital phenomena. And the manifesta- tions of life thus excluded from investigation are just those which, in my opinion, most deserve the close attention of the biologist at the present time. The eye of the biologist has ever been turned outwards to the pageant of living things by which he is surrounded. He has forgotten that though he is a spectator, and probably the only spectator endowed with intelligent curiosity, he is also a performer in this pageant. It is my belief that, so far from excluding from the sphere of inquiry those manifestations of life which can only be studied in man, we should give them a position in the full limelight of our interest. No biology can lay claim to completeness which leaves out of account such essential manifestations of life as human invention, self-expression through painting, poetry, or music, activities and aspirations which constitute the very life which each one of 5 An Introduction to a Biology us leads. Surely the way to find out about life is to study life at work ; or at play ; at any rate, in action. There is no other field at all comparable with that of human activities for such a study. It is only in human life that we can approach close to, and study minutely the very nature of, existence. §2 But there is one human activity which stands out from the rest and demands the most severely critical study. This is the process of investigation itself. It seems to me that one of the most impor- tant branches of biology should be a critical study of the process of investigation. It is a perfectly legitimate branch, because this process is indubitably a manifestation of life. It is, moreover, a branch which requires the most careful attention, because if the process of investigation be unsound the results obtained by it will be worthless. Man's theory of life, his biology, is the product of his imagination. Is it not high time, therefore, that he turned his eye inwards and pondered upon the relation between himself and the objects of his investigation ? It takes two to make a science. There are two parties to the bargain : the mind of the investigator and the things investigated. The attention of the investigator perpetually flows outwards, intent upon its object ; it does not stop to look at itself ; it is all taken up with its prey ; none of it is left over to be devoted to its source, the mind. The interests of the investigator do not lie within, but without. He has no misgivings as 6 An Introduction to a Biology to the reality of the outside world or the sound- ness of his explanations of it, because he has no misgivings as to the efficacy of his perceptive and interpretative machinery. Things as lie sees them are things as they are, because his perceptive machinery is infallible. The causes of things as he elucidates them are the true causes, because his interpretative machinery is flawless. That, at any rate, would appear to be the tacit assumption upon which he acts. The reader may object that it is the business of a philosopher and not of the biologist to deal with the process of investigation. But if the philo- sopher to whom the work is given is not an active investigator, what can he know about investiga- tion ? The eye of the philosopher is turned in- wards. His interests are within. He is interested in the outside world only as the material upon which his mind feeds, or as a mirror in which it can see itself. It seems likely, therefore, that that most inter- esting region which intervenes between the mind and things will fall between two stools. The inves- tigator is interested in the things around him : the philosopher in the mind within ; but very few are interested in the relation or interaction between the two. Now the process of investigation is a reci- procal action which takes place between the two poles, mind and object, across the region which intervenes between them. This intervening region is apt to be neglected because men tend, according to the inborn direction of their minds, . to cluster around one pole or the other. It must, however, 7 An Introduction to a Biology be admitted that there is more of the investigator in the philosopher than of the philosopher in the investigator. This is only natural. We shall see later on that it is the essential characteristic of the mind of man to extend its operation farther and farther outwards towards things. It is more likely, therefore, that the interest of the philosopher should extend outwards across the intervening region to- wards things, than that the interest of the investi- gator should extend inwards, across it, to the mind. For both are men. To the business of investigation there are, as I have said, two parties, and it is especially desirable that the investigator should have his attention drawn to the one in which he is least interested (if indeed he ever gave it a moment's thought), namely, his own mind. It must be remembered that in our attempts to solve the problems of nature we are not in the same relation to nature as a boy answering an examina- tion .paper is to the examiner. We are answering questions in an examination paper which we have ourselves set. The formulation of the problem, in however honest a mind, must involve some dim prevision of its solution. The reader may object that the problem is not formulated in the mind, but set by nature. I venture to think not. What appears to me to happen is another result of that ever outward-streaming nature of our interest, to which reference has already been made. The prob- lems originate in our mind, but no sooner have they taken shape than, all unknown to us because we will not turn the eye inwards and keep guard on our 8 An Introduction to a Biology mind, they are swept out, by the current of our interest, to the sea of things. When they have arrived there we become conscious of them for the first time, and so we think that we have found them there. So strong is this outward current that even the human voice is allowed to be carried out by it. " The facts speak for themselves," we say. But it is an illusion ; at any rate, a dangerously misleading figure of speech. Facts do not speak. If the reader should answer and say, " Well, at any rate they speak to me," I would come out and meet him on the same ground and reply, " Very well, then ; so do they speak to me, but they do not say the same thing." Facts are like the dolls of the ven- triloquist and say what we want them to. Life in the hands of the too self-confident biologist is a very docile doll in the hands of a very skilful ventriloquist. The discomfort felt by the investigator when he is asked by a layman who is taking, or trying to take, or pretending to take, an interest in his work, and asks him, " What are you trying to prove ? " is due to the fact that he sees that this question, unknown to the asker of it, reveals to him what he really is doing. He ought not to be trying to prove anything, but to find something out. But very often he knows in his heart that he hopes very much that his pet theory will be proved true by his investigations. And even if he answers, " I am verifying certain hypotheses," he condemns himself out of his own mouth. For " to verify '' literally means " to make true." 9 An Introduction to a Biology §3 In scientific investigation there are two pro- cesses. The phenomena are first to be observed and described ; and then, when this is completed, an attempt is made to interpret them. But it is very rare that this chronological sequence is strictly adhered to by the investigator. It is very rare that, as a necessary preparation of himself, he deliberately purges his mind of any preconceived interpretation of the phenomena he is about to describe. Yet if his description is to be unbiased and uncoloured by any interpretation, it is obviously necessary that he should do this. I fear that Inter- pretation (if I may personify that process for a moment) at the threshold of a piece of research does not hold back and say to Description, " Allow me — Description first." Both rush in together, with- out ceremony, hand in hand. For they are in- separable companions. And the result is that in the work of Description the hand of Interpretation can always be traced. In its simplest and least dangerous form the influence of interpretation upon description is seen in the work of the budding investigator, when he first embarks upon a piece of " original research." The subject of inquiry is usually suggested by the lad's teacher, who, in the worst cases, wishes the results of the inquiry to point in a particular direc- tion, and does not conceal his wishes from his pupil, and who in all cases indicates the lines along which, and the methods by which, the research should be carried out. But this is not a dangerous form of 10 An Introduction to a Biology the effect of interpretation upon description; be- cause the young investigator soon comes to have views of his own, and rebels against his master. The effect becomes dangerous when it is one's own unconsciously entertained interpretations, which, un- known to us, hold our hand and direct the pencil which we fondly believe to be carrying out the pure, unadulterated work of description. Instances of the way in which the work of descrip- tion, which is the recording of observation, can be distorted by preconceived interpretation will crowd up into the mind of the reader. So great an observer alTBufTon, who was an upholder of the doctrine of evolutio, according to which the adult animal existed in miniature, but complete in every detail, in the egg, said, " I have opened a great many eggs at different times, both before and after incubation, and I have convinced myself by actual observation that the chicken exists, in its entirety, in the middle of the spot on the yolk, at the moment that the egg leaves the body of the hen." The improvement of scientific instruments since Buffon's day has doubtless reduced the margin of error, but it has not prevented that which has been seen by means of these improved instruments from bearing a strange resemblance to that which the interpretation already in the mind of many a con- temporary observer made him expect to see. We have seen the manner in which description may be affected by interpretation. We may now glance at the way in which interpretation may be affected by description. The reason that the investigator has so little An Introduction to a Biology misgiving as to the correctness of his interpretations is that, however much he ought to have, he has no misgivings about his observation, nor about his descriptions of things, and we have seen that he does not, as a rule, keep observation and inter- pretation separate in his mind. So that observation merges imperceptibly into interpretation. No line is drawn to show where the one ends and the other begins ; each becomes interpenetrated by the other, and we come to exist in the pleasant delusion that interpretation is conducted in the same bright light as that in which the work of observation is carried on. A curious instance of this mutual inter pene- tration was afforded by the attitude of the Men- delian and biometric schools to the Mendelian phenomena of heredity, and the interpretation of these phenomena. The Mendelian school were so saturated with certainty as to the reality of the Mendelian phenomena, by daily contact with them, that their certainty spread across the border of ascertained fact, well into the territory of hypo- thesis. They could not understand how anyone who was familiar with the facts could doubt the hypo- thesis. The minds of the biometric school, on the other hand, were so full of scepticism as to the hypothesis that they looked with great suspicion upon the facts. § 4 The interpretation of a phenomenon consists, in current scientific phraseology, in discovering the laws which govern that phenomenon. If it be the case that the discovery of these laws is the goal of 12 An Introduction to a Biology scientific investigation, it is manifestly desirable that we should have a very clear idea of the nature of these laws. It must be admitted at once that nothing could be better adapted to the obscuring of their real nature than the phraseology of scien- tific textbooks.1 We are told that such and such phenomena are governed by such and such a law and that this law was discovered by such and such a person. We should conclude from the word " govern " that phenomena are like marionettes whose performances are regulated by things which we call " laws " behind them — at any rate, distinct from them. The discovery of these laws means, literally, the uncovering of them and, as a sort of corollary, the exposing of them to human gaze. This discovery is not supposed to take the form of an actual piercing of the ranks of the marion- ettes to the laws behind, but to consist in a deduction of the nature of these laws from the performances of the marionettes. But why this delicacy ? Why cannot we go behind the scenes and have a look at these laws, and see what they are like ? Why should there be any mystery about them ? If we are kept in the dark like this we shall begin to think we have been imposed upon. The truth, in my belief, is that we have been 1 " The strong family resemblance which is seen both in the human species and amongst animals related to each other is a direct consequence of the existence of the first law of breeding — viz. that ' like begets like,' or ' tends to produce like.' Other laws are in operation at the same time ; consequently when an organism comes within the immediate spheres of their action the effects of this and various other laws are modified to har- monise with surrounding conditions." [I have been unable to trace this quotation. — ED.] 13 An Introduction to a Biology imposed upon. The reason that we are not allowed behind the scenes is that there are no laws to be seen there. But the imposition is the offspring neither of malice nor of fun, but of thoughtlessness. It is the result of preoccupation with the results of investigation, and of inattention to the process of investigation itself. A little self-examination would reveal the fact that these laws exist, not in the world outside, but in the mind of the investigator. When the biologist — for I am dealing in this book only with the in- vestigation of vital phenomena — thinks or speaks as if he thought that he was discovering the laws determining a set of phenomena, he is, in point of fact, formulating in his own mind a law to express certain sequences or regularities that he observes in these phenomena. It may be objected here that this is common knowledge, and that such phrases as " discovering the laws which govern a set of pheno- mena " are merely figures of speech, and that no one ever really supposed that phenomena were " governed " by laws or that these laws were sub- sequently " discovered " by investigators, in the literal sense of these words. Certainly, such phrases are figures of speech ; but in my view they are very bad ones, and ought to be dropped. They are bad because they encourage the mind to travel in the direction in which it likes to travel — outwards. These laws are formulated in the mind ; but as no watch is kept on the mind they have been caught up in the stream of man's interest and swept outwards to the nether side of things. If the reader's patience will allow me, I will try 14 An Introduction to a Biology to give some idea of the picture called up in the mind, by current scientific phraseology, of the nature and whereabouts of natural laws, by describing the theory of music which I held when I was a boy of about fourteen. At that age music meant to me simply a tune. I thought that a succession of sounds was either a tune or not a tune. If it was, it was part of the order of nature ; if it was not, it was simply a noise. Tunes did not differ in merit. Who was I that I should presume to discriminate between things which were not the work of man ? I only knew two tunes, " Pop goes the weasel " and Sullivan's " Prithee, pretty maiden, will you marry me ? " I thought there existed in the world a cer- tain limited number of tunes ; I do not think I speculated as to their origin, or as to where the undiscovered tunes were. But I remember thinking with alarm that if many more men like the discoverers of " Pop goes the weasel " and " Prithee, pretty maiden," arose, all the tunes would soon be dis- covered. For I wanted very much to discover a tune myself, but I did not know where to look, or how to set about the search ; moreover, I had no means of knowing whether, or not, all the tunes had been discovered ; in which case it would be no good looking. I thought that all known tunes, together with those which might be unearthed later, had existed for all time, and had, in the literal sense of the word, been discovered — that is to say, located and brought to light by a select few who knew how to do it. This is the first stage in the history of my theory of music. The picture of the laws of Nature which I saw in '5 An Introduction to a Biology my mind's eye when, as a young man, I read in scientific books that such and such a person had discovered the laws governing such and such pheno- mena was very like my boyhood's notion of tunes. I had no reason for supposing that those who wrote what I read had not thought carefully over the meanings of the words they used. I took what I read to be literally true ; I believed that phenomena were governed by these laws ; that they really were passive agents in the hands of the powerful laws which controlled them. These laws had existed from all time, and were part of the order of the Universe. The law of Natural Selection had been discovered ; but there might perhaps be one or two laws of heredity still undiscovered. And just as I had wanted to discover a tune, so, now, I wanted very much to discover a law. In my innocence I believed that if I " discovered " the law " governing " a particular phenomenon, I should have got to the bottom of that phenomenon. The second stage in the history of my theory of music consisted in abandoning the view I have described, and in rushing to the opposite extreme of believing that tunes were simply invented by musicians, " out of their own heads," as one would have expressed it. This view raised the question why it was that some men could put together notes which the world would recognise as music, whilst others, amongst whom I was compelled to recognise myself, could not. But I imagined that if anyone chose to take the trouble to learn harmony and counterpoint and the rest, and contrived to construct a symphony which he could entice people to listen 16 An Introduction to a Biology to now and again, then in the course of time his hearers would get to know it, or rather to recognise parts of it when they heard it again ; and that in this way a man's compositions would gradually come to be recognised as music. [According to this view it will be seen that music was pure invention. The second stage in the history of my conception of natural law was analogous to the second stage in the history of my conception of music. In it I believed that natural laws were pure inventions of the human mind, and projected by the mind, or rather allowed to escape from the mind, into things. My third and present stage with regard to music is, to a great extent, a return to the first stage. Music can convey to us part of the order of nature, that part which is alive. The great musicians are the springs through which this message wells up, for us. My third and present stage with regard to natural law also returns to the first stage, but it returns a very much shorter distance. I believe that the present system of scientific laws relating to life is very much further from portraying the essence of life, than is, for instance, the eighth symphony of Beethoven. But a theory of life cannot be communicated at present by music, and one must make an attempt to communi- cate it through the inadequate medium of words. The point to which we have now reached in this attempt is that from which we see natural law to be, to a very great extent, a product of the human in- tellect.]1 1 This passage is half deleted in the MS., and was clearly intended to be re-written. C I7 An Introduction to a Biology The truth of my contention that biological laws really exist in our own mind, and not in the world outside, governing phenomena and awaiting dis- covery, is capable of a simple demonstration. If the discovery of these laws really were a detection of the principles underlying phenomena, as the conventional phrase is, and if the deeper we probed the more closely did we approach to fundamental principles, then the deeper we probed the more closely should we agree with one another. The very reverse is demonstrably the case. Our agree- ment is not directly, but inversely proportional to the depth to which we probe. The truth as it appears to me is, that we are not really burrowing under phenomena at all. We invent laws in our minds about phenomena. Then, looking the other way — i.e. not at our minds — we allow these laws to escape to the other side of, or underneath, the crust of phenomena. And then we experience the thrill of thinking that we have discovered these laws underlying phenomena. The reason that the deeper we probe the more do we disagree, is that the laws that we think we find down there, but really project there, are the products of our minds ; nay, almost the portraits of ourselves ; for the truest portrait of a man is his conception, or theory, of life. If it be asked why there are not as many laws of, say, heredity as there are men who are interested in it, the answer is that the great majority of these men are content to take their laws secondhand from other men. In a word, the fact that two men looking, as they believe, below the surface of one and the same 18 An Introduction to a Biology phenomenon, can " discover " there two profoundly different laws to explain it, seems to me to prove pretty conclusively that these laws are not de- tected underneath the phenomenon but projected below it by the men themselves. What a man sees below the surface when he looks down the Holy Well into the waters of Life is not the bottom of the well, but a picture of himself. There is another reason why laws should have flown out from the mind to the nether side of pheno- mena. The savage's interpretation of the Universe endowed everything — river, tree, and storm— with souls, and ascribed the form and the performance of these to the nature and activity of their souls. As this interpretation came gradually to be discarded in favour of " scientific " explanations of things, a void was left behind the pageant of phenomena ; and to this void it was natural that the new explanations of things should be drawn. So that when we feel inclined to congratulate ourselves on our emancipation from the crudities of an animistic interpretation of the Universe, we should ask ourselves whether in fact we have done any more than hand over the government of the Universe from a hierarchy of spirits and demons to one of principles and laws. Very little more, so far as life is concerned, I venture to think. Many an innovation in the past has been no more than the calling of an old thing by a new name. If there is a possibility that words may give a semblance of progress in interpretation, where in An Introduction to a Biology reality there is none, it is desirable that some at- tention should be paid to the relation between words and thought. Ideally, words are the medium for the com- munication of thought ; thought is the master and words the servants ; thought is wealth, words the coinage which facilitates its exchange. But actually it is not so. By subtle and imperceptible manoeuvres the word has often got the upper hand, so that thought has come to be at the beck and call of that which should be its slave. It is probable that thought and language mutually interpenetrate each other, so that at the one extreme there is pure language and at the other extreme pure thought ; in the middle an equal mixture of the two; and halfway between the middle and thought, a preponderance of thought over language ; and half-way between the middle and language, a preponderance of language over thought. But for purposes of exposition it will be necessary to make an arbitrary excision of the intervening region, and to speak of thought and language as if they were distinct, mutually exclusive things. The problem of the relation of language and thought resolves itself when, reduced to its elements, into the problem of the relation between the word and its meaning. Here again, though the word and its meaning are mutually interpenetrating and interpenetrated, it will be necessary, for the same reason, to treat of them as if they were mutually exclusive. Before I address myself to the problem I would like to say a word to any philologist who happens to read these words. I can see the smile on his 20 An Introduction to a Biology lips at any attempt to deal in a parenthesis with so vast a subject as the relation between language and thought. But if I may explain, I think I can turn the smile from one of contempt to one of at least indulgence. I, too, am appalled by the task of understanding clearly the relation between thought and language. It is because I am thus appalled that I realise that anyone to whose mind the prob- lem of this relation has not yet even presented itself is in grave danger of thinking there are no diffi- culties because he does not see them. A word and its meaning, especially in the case of ideas (with which, in this book, we have to deal), are united together by a slender, elastic bond which is now contracted, now stretched to its uttermost. The word, if we consider its whole life since its dim origin, has been perpetually changing ; so too has its meaning ; little in the case of things, much in the case of ideas. So we see the word and its mean- ing dancing to each other in an airy medium, like a pair of gnats in the lee of a gorse-bush. This, alas ! is the simplest case. The more complicated and much more common cases are those in which one word has more than one meaning, or where one meaning has more than one word to express it ; these are the cases which, in verbal life, are productive of trouble. I have attempted to con- dense into one simple picture the relation between words and their meaning. I have tried to convey my conception by a picture because it is a picture of a thing which is far less liable to change than the relation between an idea and the word by means of which it is handed from mind to mind. It may 21 An Introduction to a Biology be a poor picture. I do not ask the reader to admit that it helps to make clear the relation between the word and the thing. I ask him to admit that the fact that the difficulty of visually disentangling the movement of a pair, or a harem, of gnats does not present itself to the mind of an ostrich who has buried his head in the comfortable sand of matter hard by, does not prove that this difficulty is non- existent. De non existentibus. . . . The phenomenon of which I have given a pic- ture is the relation of the word and its meaning regarded from a point of view which envisages the whole evolution, the whole life of the word and its meaning from the time of their origin. That was perhaps too much to attempt. Let us examine the changes which take place in this relation from a nearer point of view which only envisages a period of time so short that the word has undergone no changes, or only insignificant changes, in that period. From this point of view the word is seen to remain fixed. When the word denotes a thing like bread, the thing does not change very much more than the word which denotes it. That is to say, the names of things fit closely to them ; and the word " bread " calls up in the mind the image of bread. But ideas, attributes and processes are not held closely by the words which denote them ; they are attached to the word by a bond which varies in length from case to case, but is usually fairly long. The word is the fixed point, the peg to which the leash is attached. The meaning, in such cases, is the sportive goat who is free to wander anywhere within the circle, the radius of which is the length 22 An Introduction to a Biology of the leash, and whose chief delight is to browse off and break through the hedge intended to confine him to his proper sphere, in the event of the leash being too weak for its purpose. Do I hear the criti- cism that I am merely juggling with words ? My answer is that I am trying to prevent them juggling with me — not juggling in an active sense, but in a passive one, like a chaperon who lets her charges go where they like, and by not following them, leads them into trouble. The wanderings of the meanings of a word may be followed in great detail in that fascinating work, the Oxford English Dictionary. The word " curious" was used in its Latin form only in a subjective sense, meaning full of care or pains, careful, assiduous. Amongst the subjective meanings which it came to have later were anxious, concerned, solicitous, care- ful as to the standard of excellence, difficult to satisfy. The sense in which I intend the word to be understood on the title-page of this book is one which includes all these meanings. The degradation of the meaning of a good word like " curious " is a common tragedy of verbal life. Its earliest mean- ings were qualities of the mind which were worthy of nothing but praise. It is now and has long been used in an objective sense merely to denote unusual - ness in the form or colour of objects.1 And an attempt has been made to blacken the character 1 In the " Philosophical Transactions of the Royal Society for 1703 " (Vol. XXIII., No. 286) there is " A Description of some Corals, and other curious Submarines lately sent to James Petiver, Apothecary and Fellow of the Royal Society, from the Philippine Isles, by the Reverend George Joseph Camel." 23 An Introduction to a Biology of such of the meaning as has remained in the mind, in order to stigmatise it, as it were, for its lack of taste in remaining subjective. But in spite of this attempt, its subjective meaning still retains a cer- tain dignity and independence of its own. Curiosity signifies an interest in things which convention has pronounced to be outside the sphere of the legitimate interest of mankind, in things which a conspiracy of silence chooses to ignore. A convention of Modern Science, for instance, is to regard the prying into the workings of the human mind as mere meta- physical curiosity, and the products of such researches as mere metaphysical curiosities. Sir Ray Lankester, K.C.B., F.R.S., for example, in his introduction to " Modern Science and the Illusions of Professor Bergson," says : " I am glad to write a few words by way of preface to Mr. Hugh Elliot's valuable little book, entitled 6 Modern Science and the Illu- sions of Professor Bergson.' I am glad to do this, not merely because I think that the books in which M. Bergson formulates these illusions are worthless and unprofitable matter, causing waste of time and confusion of thought to many of those who are induced to read them, but also because an unmerited importance has been attached to them by a section of the English public, misled by the ingenious and systematic advertisement of M. Bergson by those who amuse themselves with metaphysical curiosities." I Curiosity is a defiance of the conspiracy of silence, a defiance urgently needed when the topic which has been pronounced taboo is the operation of the human mind. The answer to the question " Why is this topic taboo'd by Modern Science ? " 24 An Introduction to a Biology is that the eye of science can only look outwards ; and the scientific mind regards the philosopher whose eye can look inwards as well, and at all the points along the line between mind and things, merely as a monstrosity. In the passage quoted above curiosity is probably used in an objective sense to mean the products of subjective curiosity. In the passage which follows the word " curious " is also used in its purely objec- tive sense : "To those who in a thoroughgoing way occupy themselves in collecting and comparing and classifying all the absurdities which have been put forward as e metaphysics ' or ' metaphysical specu- lation ' since the days of Aristotle, this latest effusion has, no doubt, a kind of interest such as a collector may take in a curious species of beetle. To the student of the aberrations and monstrosities of the mind of man, M. Bergson's works will always be documents of value." The above might be taken as a text for a lecture on the purely objective nature of our interest in life. A curious beetle means a bizarre beetle. It does not mean a fastidious beetle. The tragedy of the word " curious " is the result of the outward-streaming nature of man's interest. Most of the meaning has been caught up in the current and swept out from the mind, and has made its home amongst things. And even the noun from which the adjective curious is derived has been swept outwards too. When the adjective curious detached itself from its parent substantive, cure meant care. Thus cure first meant the care of the healthy ; then the successful treatment of the sick ; 25 An Introduction to a Biology and lastly the drug supposed to drive away the malady. We speak of and even believe in a cough cure. So different a meaning has " cure " come to have from that with which it began, that we could say " better use cure in the old sense than rely upon cure in the new." A word, the meaning of which is very active at the present time, is the verb to " locate." It is used in one sense in Britain, and in another sense in America, where its evolution has been more rapid ; but there are signs that the American meaning of the word is spreading eastwards across the Atlantic. To locate, in the British sense, is a transitive verb with a very well-defined, particular meaning ; it is the name for a purely subjective process, which takes place in the mind — namely, the finding out of the position of something that Nature or man is trying to conceal from you.1 By saying that it is a subjective process I mean that, though its immediate object is external to the mind (such as a short circuit in an electrical system, or a malig- nant growth in the body), the next process is within the mind — namely, the thinking out of some plan of action to be taken when the trouble has been successfully located. In America, however, the idea denoted by the word " to locate " has, first, become generalised and enlarged to mean simply " to find." I was asked last July in St. Louis if I had located a satisfactory natatorium in the town. But the meaning of the word has gone much further than this ; it has broken right away from its original 1 " A useful seaplane reconnaissance located several encampments and two permanent batteries." — Scotsman, March, 1915, re Dardanelles: , 26 An Introduction to a Biology moorings which confined it to the mind, and is used in the passive mood, as synonymous with "situate," to denote a purely objective state. The Century Club is located in West 42nd Street in New York. In this sense it is an intransitive verb ; and although in this sense it is generally used in the passive mood, it can also be used in the active mood, so that one can say that one is going to " locate " in Milwaukee. What has happened is this. At one period during its existence on the American continent this word, which originally applied to a process which took place in the mind, extended its application to processes — or rather states — which are outside the mind. Its meaning, like that of so many other words, has been caught up in the Kishon of the mind. The river Kishon swept them away — that ancient river, the river Kishon. I have used the word " locate " partly because it serves to illustrate the habit of the mind to let its offspring escape from it into the world outside, but also because the British meaning of the word denotes a process which has been neglected by the biologist in his attempt to interpret life. It is essential that he should locate the laws that relate to life. I am not asking him to agree with me in placing them in the mind, but pointing out the necessity of locating them before talking about them. It was said above that the most troublesome cases are those in which one word has more than one meaning. The reason that these cases lead to confusion is that word and meaning are mutually interpenetrating, so that the flavour given to a 27 An Introduction to a Biology word from one meaning is transmitted by that word to another and perfectly distinct meaning. For instance, the word " law " is used for those enactments which in human society adjust the relations between individuals. It is also used, as we know, for those generalisations made by man of regularities or sequences observed in phenomena. But laws, in the latter sense, natural laws as we call them, have been infected through the word as a " carrier," so to speak, with many of the attributes of law in the other sense. To such lengths has this infection proceeded that such absurd expressions as " the phenomenon obeys the law of gravity," or :< breaks all the laws of nature," are often heard. Man's reluctance to keep an eye on the changes which may be taking place in the meaning of a word is part and parcel of his reluctance to turn his eye inwards and examine the operation and furniture of his mind. The result of this reluctance is that he never takes stock of the medium whereby he conveys the results of his thoughts and researches to others, and whereby he receives such results from others. Yet if we are going to set out in earnest to understand life, we must perpetually keep a curious eye upon the relation between the word and its meaning. The reader may take exception to the sentence, "If we are going to set out in real earnest to under- stand life," and ask, " Have you the impudence to suggest that we have not yet even started to understand life ? Are you utterly ignorant of Modern Biology ? Or are you wilfully ignoring it ? Do you propose to sweep aside entirely the work of those 28 An Introduction to a Biology great investigators who have spent their lives in the service of Biology ? " Let us apply the general conclusions we arrived at with regard to the rela- tion between words and things to the word " Biology.5' The area covered by this word includes in one, let us say its western, region that great mass of (fairly pure) description of the forms and colours and behaviour of living things. In its eastern region it contains a great mass of interpretation little con- taminated by facts ; and, in the intermediate region, mixtures of the two in every conceivable proportion. Now when a man asks himself what he means by Biology he probably calls to mind the great store of (fairly well) established facts which make up the content of descriptive zoology, botany, embryology, cytology, histology and the rest. But if the man who indignantly asked the questions above, merely used the phrase Modern Biology as a bludgeon to frighten me with, he almost certainly did not ask himself what he meant by the word biology ; and in that case he made no attempt to keep the descriptive and interpretative parts of Biology strictly apart and distinct in his mind. Until he has done this, it is impossible to answer the above questions. If he will do this, I will answer that I certainly do not ignore the established facts of biology. I am concerned in this book solely with the interpretation of life ; and 1 assert that we have not yet begun to understand it. • •; •'*. j §6 • V Let us now glance at the relation between the mind of man and the phenomena of life from the historical quarter. 29 An Introduction to a Biology Suppose that when biological problems were first stated, or to speak more accurately, first gradually took shape in the minds of men, suppose that they were wrongly stated, suppose that they took the wrong shape ; the solutions of these problems will not be answers to the questions actually posed by Nature herself. I can illustrate my meaning by the following fable. There was once a man who could only play one tune, " Polly winked her eye." He played it with one finger only. He learnt it one day, not from hearing it, but from the notes, spelling it out with great difficulty. It was in the key of C major. He got the intervals between the notes correctly, allowing that there were no sharps and no flats ; but he began on the note below the one he should have begun on. He always played it like this and seemed to enjoy it. That was how he had ground out the tune for himself ; that was how he always thought of it ; and that was how it would always exist for him. But the tune was untrue owing to the initial mistake he had made. Are we certain that in our statement of biological problems we may not have begun on the wrong note ? The possibility that we may have done so deserves our earnest consideration. For my part I think we did begin on the wrong note and that, as a conse- quence, our present statement of biological problems does not correspond to the questions posed by Nature herself ; and as a further consequence, that though our solutions of those problems may be perfectly correct, they are solutions of problems posed by 30 An Introduction to a Biology the human mind. I do not maintain that these problems are entirely fictitious. I do not mean that they bear no sort of relation to the real problems ; I think they are a distorted version of the real problems, that they may be said to bear the same sort of relation to the real problems as the tune begun on the wrong note bears to the real tune. But, of course, some biological problems have been stated more correctly than others. The history of biology is a picture of the evolution of man's endeavour to interpret life. The picture of this evolution, as of all other evolutions, is the picture of a tree : leaves, twigs, branches, trunk, root, root- lets and root-hairs. This tree is the result of the solidification of the stream of mankind's interest in life. The root-hairs are his first vague curiosity and bewilderment ; the leaves his most recent publica- tions and opinions ; intervening points on the branches, trunk and roots, intervening periods in the history of biology. We will imagine further that discredited observations and unaccepted interpreta- tions were represented in this tree by dead wood, which quickly rotted and fell away. It seems to me desirable that we should occasion- ally tear ourselves away from pre-occupation with the high-water mark of our investigations ; that we should cease for a moment from our feast upon the leaves, and descending to the ground, reflect at leisure, under its genial shade, upon the form of the tree above us. Eeclining there, we should ask our- selves whether the shape of the tree into which the course of the stream of inquiry has solidified, is the right shape, whether some of the wood in it ought 31 An Introduction to a Biology not to have been cut out, and whether some that died and has long since disappeared ought not to have survived and altered the shape of the tree. In other words we should ask ourselves, are we working in the right direction ? For my own part, I believe that at certain points in the history of our attempts to interpret life wrong signals were given and that as a consequence we are at present working along the wrong lines. I am not concerned at present with the nature of this false step ; all I am concerned with now is to express my belief that the satisfaction of the biologist with our current scientific interpretation of life is the satisfac- tion of the fool with the paradise which he has built. §7 The cocksureness of the scientific biologist should surely be the cause of the gravest misgivings. The more certain a man is that he is right the more probable is it that he is wrong ; because it means that facts are as soft clay in his hands, and his cer- tainty moulds them to his purpose. It is the diffident investigator who tentatively offers us a hypothesis which, in his modest view, brings some of the facts into line, who should inspire us with confidence. It is the theory which seems to fit the facts in places but seems remote from them in others (as, for in- stance, the theory of sex based on clinical, Mendelian and cytological phenomena and upon the facts of parasitic castration) and not the theory which peremptorily brings all the facts into line, which should seem to us to be likely to be true. If a man came to me to-morrow, full of con- 32 An Introduction to a Biology fidence and certainty, and well pleased with himself, and said, " I have now got a theory which fits all the facts," I could think one of two alternative things about him. I could think that this man, by a miracle of energy, had become acquainted with all the mani- festations of sex, and that his theory did fit, down to the very smallest undulation, the surface of the phenomenon, as a glove fits a woman's hand. That is to say, I should think that he had made up the deficit in the facts by the discovery of the remainder, and that he was now able to give a theory which fitted exactly, simply because he had now got all the facts at his disposal. Or, I could think that he had not made any difference in the stock of facts at his disposal, but had invented a new theory, which fitted the same number of (but probably fewer) facts, only in the sense that a child's hand can be fitted into a steel gauntlet. That is to say, I should think he had made a new theory which really bore very little relation to the facts ; touched them at one or two points but fitted them at none. The theory might be a perfectly consistent one. He would not invent a theory which was not a consistent and organic whole. Indeed it is generally admitted that it is more important that a theory should be consistent with itself than that it should fit the facts closely. For it is considered that the worst thing that can be said against a man who is patiently trying to fit one part of his theory to one set of facts and another part of it to another set, is that the two parts of his theory are not con- sistent with one another. D 33 An Introduction to a Biology If I believed the first alternative I should think that his certainty was due to the perfect fit between theory and phenomenon ; if I believed the second I should think that certainty was due to absence of fit between theory and phenomenon. Certainty can be bred in the mind by these two extremes ; not by an intermediate stage. Are there any theories concerning vital phenomena about which certainty can be due to perfect fit ? Can there be any vital phenomenon that we know so intimately in every undulation of its form, every nuance of its colour, or every phase of its movements that there can be a theory which fits all this exactly ? Possibly in the case of some exceedingly simple phenomena (if such exist), certainty is due to perfect fit. But does it seem likely that, for instance, the certainty in the mind of so many that Natural Selection is the ex- planation of evolution, that tremendous phenomenon of the growth of life, the features of which we can but dimly discern, does it seem likely that this certainty can be due to perfect fit ? An old artist and a young artist both arrived in Venice not long ago, on the same day. At the end of a month the old artist had painted nothing ; it was too beautiful ; he knew he was not equal to painting a picture which could express to him the manifold magic of the place ; he knew that nothing that he could produce would fit reality. The young artist, however, made many sketches, with each of which he was well pleased. He had no difficulty in expressing what he saw, because he saw so much less than the old man did. Nor would he know that he saw less because Venice to him would be the 34 An Introduction to a Biology Venice that reached him through his eyes ; Venice to him was less than it was to the old man. Is not the growth of life more manifold even than Venice ? Yet the man of science thinks that he has explained evolution. Look at the matter from the point of view of the maker of the theory. Suppose he has a theory which fits a set of facts at some points. Man is in a hurry to explain what he sees. Will he not, rather than spend years in gathering new facts, impatiently, but unconsciously, round off the theory to cover the facts already before him ? Then there is a question whether a theory which fitted the facts closely would be acceptable to the mind. Is it not possible that all that the mind can understand, is mind ? I mean, it seems likely that a mind is incapable of recognising (a necessary prelim- inary to understanding) anything but the workings of another mind not very widely different from itself. That is to say, it can only recognise the usual, fairly rigidly fixed features, the deeply ingrained habits of thought — the eyes, nose, mouth and ears, so to speak, which are common to all minds. When it is remembered that two minds can be so different as to be as unintelligible to one another as is that of the poet to that of the stockbroker, or that of Beethoven to that of Weber, who, when he heard the Seventh Symphony thought that Beethoven was mad ; when we see how one mind can be so utterly unintelligible to another, is it conceivable that such a thing as a theory which has no mind (human mind, I mean) in it at all would be even recognisable, much less intelligible, to the mind ? Suppose that the 35 An Introduction to a Biology mind is suddenly confronted with an apparition, a theory, which fits a phenomenon so closely, down to the smallest crevice, that the theory showed none of the features of the human mind at all but only a cast of those of the phenomenon, the apparition would mean nothing to the mind at all (unless the phenomenon to be explained was a product of the human mind).