Part 15

But before proceeding to that, I want to go a little more in detail into the fallacy of the absolute intellectual view of Science. I say, first, that a complete summary of any object or process in Nature is impossible; secondly, that such summary as we do make is, and must inevitably and necessarily be, coloured by the underlying _feeling_ with which we approach that phase of Nature.

To take the first point. You say, Why is a complete summary not possible? A watch or other machine may be completely described and defined; why should not (with a little more knowledge) a fir-tree, or the human eye, or the solar system, be completely described and defined?

And this brings us to what may be called the Machine-view of Science. It is curious (and yet I think it will presently be seen that it is quite what might have been expected) that during this century or so, in which Machinery has played such an important part in our daily and social life, mechanical ideas have come to colour all our conceptions of Science and the Universe. Modern Science holds it as a kind of ideal (even though finding it at times difficult to realise) to reduce everything to mechanical action, and to show each process of Nature intelligible in the same sense as a Machine is intelligible. Yet this conception, this ideal, involves a complete fallacy. For the moment you come to think of it, you see that _no_ part of Nature really even resembles a machine.

What is a machine in the ordinary sense? It is an aggregation of parts put together to fulfil certain definite actions and no others. A sewing-machine fulfils the purpose of sewing, a watch fulfils that of keeping time, and they fulfil those purposes only. All their parts subserve those actions, and in that sense may be completely described--as far as just their mechanical action is concerned--the same by a thousand mechanicians. But I make bold to say that _no_ object in Nature fulfils just one action, or series of actions, and no others. On the contrary, every object fulfils an endless series of actions.

Let us take the Human Eye. And I choose this as an instance most adverse to my position, for there is no doubt that the Human Eye is one of the most highly specialised objects in creation. Helmholtz, as you know, is said to have remarked concerning it that if an Optician had sent him an instrument so defective he should have returned it with his compliments. Helmholtz was a great man, and I will not do him the injustice to suppose that he did not know what he was saying. He knew that, regarded as a machine for focussing rays of light, the eye was decidedly defective; but then he knew well enough, doubtless, _why_ it was defective--namely, because it is by no means merely such a machine, but a great deal more.

The Eye, in fact, not only fulfils the action of focussing rays of light--like an Opera Glass or a Telescope--but it might be compared to another instrument, a Photographic Camera, in respect of the fact that it forms a picture of the outer world which it throws on a sensitive plate at the back--the Retina. But then, again, it is unlike any of these "machines," in the fact that it was never made by any Optician, human or divine, for any one definite purpose. On the contrary, as we know, it has grown, it has evolved; it has come down to us over the centuries, and over thousands and thousands of centuries, from dim beginnings in the lowliest organisms who first conceived the faculty of Sight, continually modified, continually shapen by small increments in various directions, in accordance with the myriad needs of a myriad creatures, living, some of them in water, some of them in air, requiring some of them to see at close quarters, some at great distances, some by one kind of light, some by another, and so forth. So that to-day it not only contains a great range of inherited, yet latent, faculties, but it is actually, in its complex structure, an epitome and partial record of its own extraordinary history.

As an instance of this last point, let me remind you that Sight was originally a differentiation of Touch. The light, the shadows, falling on the sensitive general surface of a primitive organism provoke a tactile irritation. In the course of evolution this sense specialises itself at some point of the surface into what we call Sight. Now, to-day, when the little picture formed by the fore-part of the Human Eye falls upon the Retina at the back, it falls upon a screen formed by the myriad congregated finger-tips, so to speak, of the optic nerve--the rods and cones, so-called--which cover like a mosaic the whole ground of the Retina, and _feel_ with their sensitive points the images of the objects in the outer world. And so Sight is still Touch--it is the power of feeling or touching at a distance--as one sometimes in fact becomes aware in looking at things.

But then again on and beyond all these things--beyond the focussing and photographing of rays, beyond the latent adaptations to the needs of innumerable creatures, and the epitomising of ages of evolution--the Human Eye has faculties even more far-reaching perhaps and wonderful. It is the marvellous organ of human Expression. By the dilatations and contractions of the iris, by the altering convexities of the lens and the eyeball, and in a hundred other ways, it manages somehow to convey intelligence of Command, Control, Power, of Pity, Love, Sympathy, and all those myriad emotions which flit through the human mind--an endless series--a perfect encyclopædia. It is difficult even to imagine the eye without this power of language. And what other functions it may have it is not necessary to inquire. Highly specialised though it is, it is already obvious enough that to call it a Machine for focussing rays of light is monstrously and ludicrously inadequate--even as it would be to call the Heart (the very centre of emotion and life, and the symbol of human love and courage) a common Pump.

Nature is an infinitude, and can at no point be circumscribed by the human intellect. Nor obviously is there any sense in taking one little portion of Nature and isolating it from the rest, and then describing it exhaustively _as if_ it really were so isolated. A thousand mechanicians will agree, as I have said, in their description of a machine, because in fact they will agree to view the machine just in the one aspect of its particular action; but ask a thousand people to describe one and the same face--or, better still, get a thousand portrait-painters, skilled in their art, to paint portraits of the same face--and you know perfectly well that all the likenesses will be different. And why will they be different? Simply because every face, however rude, has infinite sides, infinite aspects, and each painter selects what he paints from his own point of view. And the same is true of every object and process in Nature.

Then if these things are true (you ask again) how is it that scientific men _do_ arrive at definite conclusions, and do agree with each other so far as they do?

It is, and obviously must be, by the method of isolation; by the method of selecting certain aspects of the problems presented to them, and ignoring others. For since _all_ the relations of any phenomenon of Nature cannot possibly be compassed, the only way _must_ be to ignore some and concentrate attention on others; and when there is a kind of tacit agreement as to which aspects shall be passed over and which considered, there is naturally an agreement in the results. Thus by this method, waiving all other aspects of the problem, the Eye may be described and defined as an optical instrument, the Heart as a common Pump, and the Solar System as a neat illustration of certain mechanical laws discovered by Galileo and Newton.

On the subject of the Solar System and Astronomy I will dwell for a few moments, as here--in this great example of the perfection of Modern Science--we have again a case apparently most adverse to my contention. The generalisations by which Newton established the nature of the planetary orbits has been a wonder to succeeding generations; the positions of the planets can be foretold, eclipses can be calculated with amazing accuracy. Yet every tyro in Mathematics knows that the equations which give these results can only be solved by what is called "neglecting small quantities"--that is, the problems cannot be solved in their entirety, but by leaving out certain terms and elements, which do not appear important, a solution can be approached. And naturally it has been an important point to show that these small quantities _may_ be safely neglected. In the case, for instance, of the orbits of the planets round the sun, and of the moon round the earth, it was for a long time taken as proved that the small variations in the shape and position of each elliptic orbit would never be accompanied by any permanent increase or diminution in its _size_--that is, that the _mean distances_ of the planets from the sun, and of the moon from the earth, would always remain within certain limits. Of late years however Professor George Darwin, taking up one of these poor little neglected quantities in the theory of the moon, found that it indicated after all very vast and very permanent, though of course very slow, changes in her mean distance from the earth; so that now it appears probable that the Moon's true orbit, instead of being a limited ellipse, is a continually though gradually enlarging Spiral, which may some day carry the Moon to a great distance from the earth. If an eclipse were calculated for twenty years in advance on the Elliptic theory or the Spiral theory, it would probably--so slow would be the divergence--make no perceptible difference; but in a hundred centuries the two theories would lead to results utterly different.

Thus the certitude of Astronomy as a Science arises largely from the fact that our _times_ are so brief compared with Celestial periods. The proper periods of Celestial changes are to be reckoned by thousands, perhaps millions, of years; but we, ignoring _that_ aspect of the problem, fix our observations on one little point of time, and are quite satisfied with the result!

As another illustration of my meaning, consider the Fixed Stars, so-called. These stars in their groups and clusters, which we know so well by sight, have remained apparently in the very same, or nearly the same, relative positions during all the 2,000 or 3,000 years that we have any record of the shapes of the Constellations. Yet now by minute telescopic and spectroscopic examination we know that they are moving, and have been moving all the time, in various differing directions with great velocities, amounting to miles per second. Nevertheless, so great are the spaces concerned, so great the times, that all this long period has not sufficed to bring them into any greatly changed attitude with regard to each other! What would you think of an intelligent foreigner who, coming to England to study the game of cricket, remained on the cricket field for a quarter of a minute--during which time the players would have hardly changed their positions--and having noted a few points, went away and wrote a volume on the laws of the game? And what are we to think of poor little Man who, having noted the stars for a few centuries, is so sure that he understands their movements, and that he is versed in all the "ordinances of heaven."

Thus it would appear that every Nature-problem is so enormously complex that it can only be got at by what we have called the Method of Ignorance. Let us take a practical Science problem like that of Vaccination. The question here, put in its simplest terms, seems to be, Whether Vaccination, with calf or human lymph, prevents or alleviates Smallpox; and if it does, whether it does so without engendering other evils at least as great. At first sight this may appear to you a very simple question, and easy to solve; but the moment you come to think about it, you see its extreme complexity. In the first place, it is obvious that in a question like this, individual cases afford no test. It is obvious that the fact that A. is vaccinated and has not taken small-pox proves nothing, for there is nothing to show that he would have taken it if he had not been vaccinated. And when you have got people vaccinated by the hundred and the thousand, you still are not certain; for these people may belong to a certain class, or a certain locality, or may have certain habits and conditions of life, which may account for their comparative immunity, and these causes must be eliminated before any definite conclusion can be reached. Thus it is not till the great mass of the population is vaccinated that we can expect reliable statistics. But the introduction of a practice of this kind on so great a scale necessarily takes a long period of years, and meanwhile changes are taking place in the habits of the people, Sanitation is being improved, customs of Diet are altering, possibly (as so often happens in the history of an epidemic) the disease, having run its course, is beginning spontaneously to decline. And thus another series of possible causes has to be discussed.

Then, supposing the question, notwithstanding all these difficulties, to be so far settled in favour of the present system--there still arises that whole other series of difficulties with regard to the possibility of the spread of _other_ diseases by the practice, and with regard to the _extent_ of such spread, before we can arrive at any finale. This series of questions is almost as complex as the other; and it includes that great element of uncertainty--the question what interval of time may elapse between inoculation with a disease and its actual appearance. For if in several cases children break out with erysipelas immediately after vaccination, of course there is a certain presumption that vaccination has been the cause; but if the erysipelas only appears some years after, its connection with the operation may, though real, be impossible to trace.

The matter standing thus, it seems to us almost a mystery how it was that the medical authorities of the early days of Jennerism were so cocksure of their conclusions--until we remember that in arriving at those conclusions they practically _ignored_ all these other points that I have mentioned, like changes of Sanitation, spontaneous decline of Small-pox, the spread of other diseases, etc., and simply limited themselves to one small aspect of the problem. But now, after this interval of time, when the neglected facts and aspects have meanwhile _forced_ themselves on our attention, how remarkable is the change of attitude as evidenced by the finding of the late Royal Commission! (1896).

From all this do not understand me to deride Science--for I have no intention of doing that; on the contrary, I think the debt we owe to modern investigation quite incalculable; but I only wish to warn you how complex all these problems are, how impossible that notion of settling even one of them by a cut-and-dried intellectual formula.

But you will ask (for this is the second point I mentioned some little time back) _how_ people's emotions and feelings come in to colour their scientific conclusions? And the answer is--very simply, namely by directing their choice as to what aspects of the problem they will ignore and what aspects they will envisage; by determining their point of view, in fact. To return to that illustration of several portrait-painters painting the same face; just as each painter is led by his feeling, his sympathies, his general temperament, to select certain points in the face and to pass over others, so each group of scientific men in each generation is led by its sympathies, its idiosyncrasies, to envisage certain aspects of the problems of the day and to ignore others.

The whole history of Science illustrates this. We are all familiar with the way in which the predilections of religious feeling in the time of Copernicus and Galileo retarded the progress of astronomical Science. As long as people believed that a divine drama of redemption had been enacted on this earth alone, they naturally concluded that this earth was the centre of the universe, and refused to look at facts which contradicted their conclusion. When Galileo turned his newly-made telescope on Jupiter and saw it circled by its satellites, he saw in this an image of the Copernican system and of the planets circling round the central Sun; but when he asked others to share his observation and his inference, they would not. "O, my dear Kepler," he writes in a letter to his fellow astronomer, "how I wish we could have one hearty laugh together. Here at Padua is the principal Professor of Philosophy, whom I have repeatedly and urgently requested to look at the moon and planets through my glass; but he pertinaciously refuses to do so. What shouts of laughter we should have at this glorious folly!"

And though we laugh at the folly of those before us, we do the same things ourselves to-day. Take the science of Political Economy. A revolution has taken place in that, almost comparable to the change from the geocentric to the heliocentric view in Astronomy. During the distinctively commercial period of the last 100 years, the leading students of social science, being themselves filled with the spirit of the time, have been fain to look upon the acquisition of private wealth as the one absorbing motive of human nature; and so it has come about that the economists, from Adam Smith to John Stuart Mill, have founded their science on self-seeking and competition, as the base of their analysis. To-day another series of economists coming to the front--their minds preoccupied with the great facts of Community of life and Co-operation--have discovered that Society is in the main an illustration of these latter principles, and have evolved a quite new phase of the science. It is not that Society has changed so much during this period, as that the altered point of view of the students of Society has caused them simply to fix their attention on a different aspect of the problem and a different range of facts.

I have alluded already to the way in which the prevalent use of Machinery in practical life has affected our mental outlook on the world. It is curious that during this mechanical age of the last 100 years or so, we have not only come to regard Society in a mechanical light, as a concourse of separate individuals bound together by a mere cash-nexus, but have extended the same idea to the universe at large, which we look upon as a concourse of separate atoms, associated together by gravitation, or possibly by mere mutual impact. Yet it is certain that both these views are false, since the individuals who compose Society are _not_ separate from each other; and the theory that the universe, in its ultimate analysis, is composed of a vast number of discrete atoms is simply unthinkable.

When we come to a practical and modern question like Medicine, the influence of the spirit in which it is approached on the course of the science is very easy to see. For if the science of Medicine is approached (as it perhaps mostly is to-day) in a spirit of combined Fear and Self-indulgence--fear for one's own personal safety, combined with a kind of anxiety to continue living in the indulgence of habits known to be unhealthy--if it is approached in this uncomfortable and contradictory state of mind, it is pretty obvious that its course will be similarly uncomfortable: that it will consist for the most part in a search for drugs which shall, without effort on our part, palliate the effects of our misconduct; in the discovery, as in a kind of nightmare, that the air round us is full of billions of microbes; in a terrified study of these messengers of disease, and in a frantic effort to ward them off by inoculations, vaccinations, vivisections, and so forth, without end.

If, on the other hand, the science is approached from quite a different side--from that of the love of Health, and the desire to make life lovely, beautiful and clean; if the student is filled not only with this, but with a great belief in the essential _power_ of Man, and his command in creation, to control not only all these little microbes whose name is Legion, but through his mind all the processes of his body; then it is obvious enough that a whole series of different facts will arise before his eyes and become the subject of his study--facts of sanitation, of the laws of cleanly life, diet, clothing and so forth, methods of control, and the details and practice of the influence of the mental upon the physical part of man--facts quite equally real with the others, equally important, equally numerous perhaps and complex, but forming a totally different range of science.

In conclusion, you begin to see doubtless that I do not believe in a science of mere Formulas, which can be poured from one brain to another like water in a pot. I believe in something more organic to Humanity--which shall combine Sense, Intellect and Soul; which shall include the keenest training of the Senses, the exactest use of the Brain, and the subordination of both of these to the finest and most generous attitude of Man towards Nature.

To come to quite practical aspects, I think that Physical Science, and for that matter Natural History too, ought to be founded on the closest observation and actual intimacy with Nature. It is notorious that in many respects the perceptions, the Nature-intuitions, of savage races far outdo those of civilised man. We have let that side go slack, and too often the man of science when he comes out of his study is a mere baby in the external world. I look back with a kind of shame when I think that I studied the mathematical side of Astronomy for three or four years at Cambridge and absolutely at the time hardly knew one star from another in the sky. But such are the methods of teaching that have been in use. They ought however to be reversed, and practical acquaintance with the facts should come a long way first, and then be succeeded by inductive and deductive reasoning when the difficulties of the subject have forced themselves on the student's mind.

Then in Natural History and Botany I think that we have hitherto not only neglected the perceptive side, but also what may be called the intuitive and emotional aspects. If any one will attend to the subject, I believe they will perceive that there are dormant in the mind the finest intuitions and instincts of relationship to the various animals and plants--intuitions which have played a far more important part in the life of barbaric races than they do to-day.[41] Primitive peoples have a remarkable instinct of the medicinal and dietetic uses of herbs and plants--an instinct which we also find well developed among animals--and I believe that this kind of knowledge would grow largely if, so to speak, it were given a chance. The formal classification of animals and plants--which now forms the main part of these sciences--would then come in simply as an aid and an auxiliary to the more direct and human study.