To these dismal forecasts it is reasonable to reply that there is nothing novel in the present situation. The human race has always known enough to wreck itself, and its abounding folly has always inspired its wise men with the gravest apprehension for its future. Yet, either by chance or providence, it has always known also how to avoid destruction. It has never known enough to make itself happy; nor does it know enough to do so now. Its future has always been precarious, because it has always been uncertain whether it would use its knowledge well or ill, to improve or to ruin itself. It has always had a choice between alternative policies, and it has so now.
What sense then is there in making such a fuss about the present crisis? It is a particularly plain case of the perennial choice of Hercules. What is needed is just a little clear thinking and plain speaking to a society more than usually debauched by a long regime of flattery, propaganda, and subterfuge. Mankind can make a fool of itself, as it always could; if it does, its blood will be on its own head. For it has knowledge enough to avoid the dangers that threaten it, if it will use its knowledge properly.
II
The first fact to be enunciated plainly, and faced, until it grows familiar, and its import is appreciated, is that, biologically speaking, Man has ceased to be a progressive species long ago. The evolutionary impetus which carried our ancestors from the level of the ape or even of the lemur, through such subhuman types as Pithecanthropus, and the Heidelberg and Neanderthal men, to ‘modern’ man, seems to have spent itself by the middle of the palæolithic period, i.e. say, thirty thousand years ago. At any rate, the Cro-Magnon people of the Aurignacian age, who then appeared upon the scene, were in no wise inferior to any subsequent race of men, either in stature or in brain capacity. They average six feet three inches in height, with one-sixth more brains than the modern European. So far indeed as their physical remains can indicate, they seem to have been very definitely the finest race of human beings that has ever existed. If we have improved on them, it has probably been only in such minor matters as resistance to the microbes of the many diseases which flourish among dense populations under slum conditions. Against that probability have to be set such certainties as that our toes and many of our muscles are being atrophied and that we are getting more liable to caries and baldness.
This remarkable fact of the arrest of his biological development is certainly the greatest mystery in the history of Man. It at once raises two further questions: In the first place, how did it happen, and what caused it? And, secondly, what has enabled man, nevertheless, to progress in other respects, in knowledge, in power, and in culture?
To answer the first question we cannot do better than argue back from what is now the most salient feature about man’s biological position, namely that his survival is determined far more by his relations to the social group to which he belongs than by personal efficiency: hence he can draw on the collective resources of his tribe, and, to a growing extent, gets emancipated from the control of natural selection. Thus social selection and the survival of societies profoundly modify (and often defeat), the working of natural selection. The advantages are obvious; it is no longer essential for a member of a society that collectively controls the conditions of existence to develop any high degree of personal capacity, in order to survive. A single wise and provident minister, like Joseph, is enough to keep alive millions of Pharaoh’s subjects through the lean years of famine. But the inferior and incompetent survive with the rest.
Now, if we suppose that by mid-palæolithic times man had established his ascendency over nature and perfected his social organization sufficiently to render these services to his fellows, we have suggested a possible cause of the cessation of biological progress. For social influences are as likely as not to be ‘contra-selective,’ that is, to tend to preserve by preference the stocks which are less viable from a merely biological point of view. They are markedly so at present, and it would be asking too much to expect the tribal chiefs of early men to have been wise and provident enough to see to it that their social institutions were eugenical in their effects. We cannot even now find such a pitch of wisdom and providence in the controllers of our destinies.
III
The answer to the second question is much easier. The human race has continued to progress in its culture, in its knowledge, in its power over nature, because it has devised institutions which have created for it a continuous social memory that defies death. Now, as ever, the wisest and the best must die, while their place is taken by babies born as ignorant and void of knowledge as in the beginning. Only there has been invented apparatus which relieves the civilized baby of his hereditary ignorance, and renders him potentially the heir to all the wisdom of the ages.
In the first place, Language not only extends enormously the possibilities of co-operation and common action, but also renders possible the consolidation of customs and their preservation by oral tradition. In the next place, Writing enables a society to record all that it considers worth remembering. Upon these two inventions may be reared vast intricate structures, religious, political, social, and scientific, which knit together and dominate human societies from generation to generation, and create the conditions for an almost mechanical accumulation of knowledge.