Science Made Plain

Biology for Everyman. By Sir J. Arthur Thomson. Two vols. (Dent. 15s.) IT is a very difficult thing to make the truths of s2ienec plain to the man in the street. One might say it was hopeless.

I am reminded of the story of_the Russian dancer who was

asked what she meant by a certain dance : she replied, that if her meaning could be conveyed in a few simple words why should she go to the very great pains of dancing it ? The

scientist might equally complain that if the truth has lain hidden from all but the largest and most acute intelligences, how can the mere medium of words make it accessible to the scatter-brained vulgar ? Scientific truth is not a fortress,

which when it has been stormed by the soldier can be throWn open to the twopence-paying civilian to wheel his perambulator in. It is more like a mountain—almost as hard to climb for

those who come after as for .those who went before. • Yet the attempt must be made, one recognizes that. For science is today what religion was—an attempt to discover

the nature of Nature ; the reflex of the human mind to the stimulus of perception. Every. religion has to broaden its

base among the simple : science must, too. But how shall theinfirm be made even partially to apprehend that mountain, which clearly they cannot climb ?

There are two possible techniques. the climber may take them for carriage-exercise among the foothills. He may demonstrate to them, on an easy slope,- the elements of the method of climbing. After all, he 'will suggest to them, the mountain is only another slope like thls—higher of course. and steeper, but not in its nature dissimilar (and of those

conditions which are peculiar to the climbing of very great heights he will say nothing). The other technique is totally different. He will neglect the literal similitude of the foot- hills. He will play the poet's part—he will try, that is to

say, to image to them those peaks which they cannot approach.

He will describe the mountain, show them pictures of it, models of it ; he will take them to look at its outline from

far off.

Of religions, the first technique is that adopted by Islam, for example : a few simple dogmas, that can be believed by anyone capable of belief at all ; and a few simple if drastic

rules of conduct, that all believers can practise. The second technique is the technique of the Sermon on the Mount=- the technique of the picture, of the parable. To turn to science, the first is the technique of the stinks-master at a public school. The second is the technique of the mathe-

matical physicist.

The suggestion that the scientist, that exact fellow, speaks

to us in parables, may come with a slight shock to some readers : yet such is the fact.- For the discoveries in physics which have made the last quarter-century spectacular cannot be expressed literally in language. Language is a vehicle invented to meet the needs of common experience : but the experiences Of the physicist are beyond the common, and do not obey the axioms of the common. Though numbers can express them literally, words cannot. Consider light, for example. We were brought up. on a wave-theory—to believe that light- is waves in the ether. But that, though A true parable, is not literal truth. For now comes the quantuin- theory, showing that in certain respects light must be con- sidered as a volley of particles. Or consider the electron, which we were taught to regard as a kind of particle. Now

comes the technique of wive-mechanics, which shows to us the eleetrdn behaving in certain respects like waves. Waves that

are particles, and particles that are waves ? Taken literally, the two theories are contradictory . . but then, taken literally it is a contradiction to call mankind both a flock of sheep and the ground where a sower goes forth to sow his

seed.

This necessity of speaking in parables is most marked .in physics, at present, because it is the most advanced of the sciences. But as each science passes beyond what is directly under its nose and reaches the mathematical stage, the same thing comes about.. It is rapidly coming about in biology, _ for, nstance--_-it bas. long been ,impheft in any account of the behaviour of genes. As the science of biology advances, so will the necessity.. of .parables. to-disseminate its,,fliscoyerka. increase.

The danger of this method of popularization, of course, is the same for science as' for religion—the danger that the parable will be taken literally, or at least that- the frontier betWeen the literal and the metaphorical will be ill-drawn. How great this danger is we have had ample witness lately,_ if we needed any, in the spate of dinner-table talk about rein. tivity and the curvature of space ! Perhaps it is for fear of this danger that Professors Andrade and Huxley, in the first book under review, stick- so strictly to the foothills. It is Strange to find a modern compendium of vulgate science wherein the name of Einstein is not mentioned, nor are electrons, nor are chromosomes ! Wherein the whole subject of heredity is covered in five hundred words, without any allusion to sex ! Indeed, recent radical discoveries play little or no part in this book. But, granted its limitations, it is extremely good of its kind. It is not a compendium of know- ledge at all, nor even a skeleton—rather it is an appetizer. It tells the reader a great deal about his immediate environ- ment, and it does so accurately and without dullness. The biological chapters especially are written with great skill most notably in the picture they present of the elements of physiology. There is, of course, a complete absence of chichi, for which one cannot be too thankful.

. Sir J. Arthur Thompson's posthumous work is .of. a very different kind. To begin with, it is vast and elaborately detailed : a leisurely survey of the whole field of living things. And yet I cannot but feel that it is misnamed. The more of it one reads, the more one feels that Sir Arthur was a natu- ralist, not a biologist at all. His interest is in a minute in- spection of the picture presented by nature : he keeps, of course, a few theoretical bees in his bonnet, and lets them out when opportunity arises, but primarily he is not a scientist his biases, his emphases are not scientific. How can I illus- trate the difference ? To the biologist there are at the present moment few creatures so interesting as the drosophila melano-. ;aster, the inconspicuous fruitfly ; because its short life-span and this and that render it peculiarly amenable to certain experiments. But Sir Arthur was without question more interested in the partridge, because of the beauty of its plumage.

Regarded, however, as a survey of Natural History, this book is as admirable a one as you can hope to find. The last book of these three is inconsiderable, and serves no particular purpose. It is aimed at children, and shows this by a tommy- rot dressing about roads and sign-posts and so on. Of course, in writing for children one should attack the imagination. But one should do it with the subject itself (as Professor Andrade and Professor Huxley do), not with a let's-pretend coating of it. It is no good coating dull facts with cheap sugar—or the child will lick off the sugar and leave the facts.

RICHARD HUGHES.