Progress and History

by Unknown

Before anything can be said of the conclusions in this branch of science one preliminary remark has to be made. From the philosophical point of view the science of life includes all other, for man is a living animal, and science is the work of his co-operating mind, one of the functions of his living activity. What this involves on the philosophical side does not concern us here, but it is necessary to indicate here the nature of the contact between the two great divisions of science, the mechanical and the biological, considered purely as sciences. For, though we know that our consciousness as a function of life must in some form come into the science of life, and is, in a sense, above it all, we are yet able to draw conclusions, apparently of infinite scope, about the behaviour of all living things around us and including ourselves, just as we do about a stone or a star. And we are interested in this chapter in seeing how this drawing of general conclusions keeps growing with regard to the phenomena of life, just as it has grown with regard to all other phenomena, and we have to consider what sort of difference there is between the one class of generalizations and the other.

For those of us who are content to rest their conclusions on the positively known, who, while not setting any limits to the possible extension of knowledge, are not prepared to dogmatize about it, it is still necessary to draw a line. A dualism remains, name and fact alike abhorrent to the completely logical philosophic mind. On the one hand the ordinary laws of physical science are constantly extending their sphere; on the other, the fact of life still remains unexplained by them, and becomes in itself more and more marvellous as we investigate it. The general position remains much as Johannes Müller expressed it about the middle of the last century, himself sometimes described as the central figure in the history of modern physiology. 'Though there appears to be something in the phenomena of living beings which cannot be explained by ordinary mechanical, physical, or chemical laws, much may be so explained, and we may without fear push these explanations as far as we can, so long as we keep to the solid ground of observation and experiment.' Since this was written the double process has gone on apace. The chemistry and physics of living matter are being sketched, and biologists are more and more inclined to study the mechanical expression of the facts of life. Mr. Bateson, for instance, tells us that the greatest advance that we can foresee will be made 'when it is possible to connect the geometrical phenomena of development with the chemical'. The process of applying physical laws to life follows, it would seem, the reverse order of their original development. First the chemistry of organic matter was investigated, then the physical attraction of their molecules, and now their geometry is in question. So, says Professor Bateson, the 'geometrical symmetry of living things is the key to a knowledge of their regularity and the forces which cause it. In the symmetry of the dividing cell the basis of that resemblance which we call Heredity is contained'.

But such work as this is still largely speculative and in the future. It does not solve the secret of life. It does not affect the fact of consciousness which we are free to conceive, if we will, as the other side of what we call matter, evolving with it from the most rudimentary forms into the highest known form in man, or still further into some super-personal or universal form. This, however, is philosophy or metaphysics. We are here concerned with the progress of science, in one of its two great departments, i.e. knowledge about life and all its known manifestations, which from Aristotle onwards have been subjected to a scrutiny similar to that which has been given to the physical facts of the universe and with results in many points similar also. But the facts, although superficially more familiar, are infinitely more complicated, and the scrutiny has only commenced in earnest some hundred years ago. Considering the short space for this concentrated and systematic study, the results are at least as wonderful as those achieved by the physicists. Two or three points of suggestive analogy between the courses of the two great branches of science may here be mentioned.

We will put first the fundamental question on which, as we have seen, no final answer has yet been reached: What is life, and is there any evidence of life arising from the non-living? Now this baffling and probably unanswerable question—unanswerable, that is, in terms which go beyond the physical concomitants of life—has played the part in biology which the alchemists' quest played in chemistry. It led by the way to a host of positive discoveries. Aristotle, the father of biology, believed in spontaneous generation. He was puzzled by the case of parasites, especially in putrefying matter. Even Harvey, who made the first great definite discovery about the mechanism of the body, agreed with Aristotle in this error. It was left for the minute and careful inquirers of the nineteenth century to dispose of the myth. It was only after centuries of inquiry that the truth was established that life, as we know it, only arises from life. But the whole course of the inquiry had illuminated the nature of life and had brought together facts as to living things of all kinds, plants and animals, great and small, which show superficially the widest difference. Illumination by unification is here the note, as clearly as in the mathematical-physical sciences. All living things are found to be built up from cells and each cell to be an organism, a being, that is, with certain qualities belonging to it as a whole, which cannot be predicated of any collection of parts not an organism. The cell is such an organism, just as the animal is an organism, and among its qualities as an organism is the power of growth by assimilating material different from itself. Yet, in spite of this assimilation and constant change, it grows and decays as one whole and reproduces its like.

Another point of analogy between the animate and the inanimate sphere is that the process of study in both has been from the larger to the smaller elements. The microscope has played at least as decisive a part as the telescope, and it dates from about the same time, at the beginning of the seventeenth century. Since then it has penetrated farther and farther into the infinitesimal elements of life and matter, and in each case there seems to be no assignable limit to our analysis. The cell is broken up into physiological units to which almost every investigator gives a new name. We are now confronted by the fascinating theory of Arrhenius of an infinite universe filled with vital spores, wafted about by radio-activity, and beginning their upward course of evolution wherever they find a kindly soil on which to rest. To such a vision the hopes and fears of mortal existence, catastrophes of nature or of society, even the decay of man, seem transient and trivial, and the infinities embrace.

A third point, perhaps the most important in the comparison, is the way by which the order of science has entered into our notions of life, through a great theory, the theory of evolution or the doctrine of descent. In this we find a solid basis for the co-ordination of facts: it was the rise of this theory in the hands of one thinker of unconquerable patience and love of truth which has put the study of biology in the pre-eminent position which it now holds. But it is necessary to consider the evolution theory as something both older and wider than Darwin's presentation of it. Darwin's work was to suggest a vera causa for a process which earlier philosophers had imagined almost from the beginning of abstract thought. He observed and collected a multitude of facts which made his explanations of the change of species—within their limits—as convincing as they are plausible. But the idea that species change, by slow and regular steps, was an old one, and his particular explanations, natural and sexual selection, are seen on further reflection to have only a limited scope.

This is no place, of course, to discuss the details of the greatest and most vexed question in the whole science of life. But it belongs to our argument to consider it from one or two general points of view. Its analogies with, and its differences from, the great generalizations of mathematical physics, are both highly instructive. The first crude hypothesis of the gradual evolution of various vegetable and animal forms from one another may be found in the earliest Greek thinkers, just as Pythagoras and Aristarchus anticipated the Copernican theory. Aristotle gave the idea a philosophic statement which only the fuller knowledge of our own time enables us to appreciate. He traced the gradual progression in nature from the inorganic to the organic, and among living things from the simpler to the higher forms. But his knowledge of the facts was insufficient: the Greeks had no microscope, and the dissecting knife was forbidden on the human subject. Then, as these things were gradually added to science from the seventeenth century onwards, and the record of the rocks gave the confirmation of palaeontology, the whole realm of living nature was gradually unfolded before us, every form connected both in function and in history with every other, every organ fulfilling a necessary part, either now or in the past, and growing and changing to gain a more perfect accord with its environment. Such is the supreme conception which now dominates biological science much as the Newtonian theory has dominated physics for two hundred years; and it is idle to debate whether this new idea is different in kind or only in degree from the great law of physics. It is a general notion or law which brings together and explains myriads of hitherto unrelated particulars; it has been established by observation and experiment working on a previous hypothesis; it involves measurement, as all accurate observation must, and it gives us an increasing power of prediction. So far, therefore, we must class it with the great mathematical laws and dissent from M. Bergson. But seeing that the multitudinous facts far surpass our powers of complete colligation, that much in the vital process is still obscure, that we are conscious in ourselves of a power of shaping circumstances which we are inclined in various degrees to attribute to other living things, so far we recognize a profound difference between the laws of life and the laws of physics, and pay our respects to M. Bergson and his allies of the neo-vitalist school. Not for the first time in history we have to seek the truth in the reconciliation, or at least the cohabitation, of apparent contradictories.

To us who are concerned in tracing the progress of mankind as a whole, and constantly find the roots of progress in the growth of the social spirit, the development, that is, of unity of spirit and of action on a wider and deeper scale, there is one aspect of biological truth, as the evolutionists have lately revealed it, which is of special interest. The living thing is an organism of which the characteristic is the constant effort to preserve its unity. This is in fact the definition of an organism. It only dies or suffers diminution in order to reproduce itself, and the new creature repeats by some sort of organic memory the same preservative acts that its parents did. We recognize life by these manifestations. A merely material, non-living thing, such as a crystal, cannot thus make good its loss, nor can it assimilate unlike substance and make it a part of itself. But these things are of the nature of life. Now mankind, as a whole, has, if our argument is correct, this characteristic of an organism: it is bound together by more than mechanical or accidental links. It is one by the nature of its being, and the study of mankind, the highest branch of the science of life, rests, or should rest, upon the basis of those common functions by which humanity is held together and distinguished from the rest of the animate world.

Just as in passing from the mechanical sciences to that of life, we noticed that the general laws of the lower sphere still held good, but that new factors not analysable into those of the former had to be reckoned with, so in passing from the animate realm, as a whole, to man its highest member, we find that, while animal, and subject to the general laws of animality, he adds features which distinguish him as another order and cannot be found elsewhere. His unity as an organism has a progressive quality possessed by no other species. Step by step his mind advances into the recesses of time and space, and makes the farthest objects that his mind can reach a part of his being. His unity of organization, of which the humblest animalcule is a simple type, goes far beyond the preservation or even the improvement of his species: it touches the infinite though it cannot contain it. To trace this widening process is the true key to progress, the idée-mère of history. For while man's evolution has its practical side, like that of other species,—the needs of nutrition, of reproduction, of adapting himself to his environment,—with man this is the basis and not the end. The end is, first the organization of himself as a world-being, conscious of his unity, and then the illimitable conquest of truth and goodness as far as his ever-growing powers extend.

Man's reason is thus, as philosophers have always taught, his special characteristic, and takes the place for him, on a higher plane, of the law of organic growth common to all living things. In this we join hands, across two thousand years, with Aristotle: he would have understood us and used almost identical language. But the content of the words as we use them and their applications are immeasurably greater.