Partly to the influence of Genesis, partly to the apparent facts of observation, and partly to the views which would naturally be held by poets and thinkers, we may attribute the belief which has been held by man, simple and philosophic alike, since first men began to think, until, we may say, the third quarter of the nineteenth century—the belief that the lowest of living things arose by a natural genesis or so-called spontaneous generation in suitable materials already provided on the land or in the sea. It was not suggested or believed that very large and conspicuous living creatures were thus bred, though it is true that the ancients thought even crocodiles to be generated by the action of the sun upon the slime of the Nile. The living creatures supposed to arise naturally in the womb of earth—the all-mother—were mostly small creatures, like insects and worms. The ordinary belief of the uninstructed to-day—a belief which they share with the greatest thinkers of antiquity and the Renaissance—is that the cheese-mite, for instance, is evolved from the substance of the cheese. Now, it is of particular moment to observe the vast contrast between the significance of this belief prior to the publication of “The Origin of Species” and its significance to-day. Before we accepted the doctrine of organic evolution, the supposed spontaneous origin of the cheese-mite in cheese, or of the maggot in putrid meat, was of no very great moment; a maggot or a cheese-mite is an extremely insignificant object. So far as the great problems of the universe are concerned, a cheese-mite, as we say, is neither “here nor there,” and its spontaneous generation was not regarded as a fact of any great moment.
But then there arose Darwin, who, in establishing the doctrine of organic evolution already supported by his own grandfather, by Lamarck, and Goethe, and Herbert Spencer, gave an entirely new importance to the question. He demonstrated how we could conceive the evolution of all organisms, including man, from a “few simple forms,” under the continuous influence of natural law; and thus such forms ceased to be insignificant, and the manner of their genesis came to be a vital problem in more senses than one. Such organisms—the mite, the maggot, and even the mould—could no longer be regarded as insignificant, for they were revealed as not unlike the ancestors of man himself.
Evolution a Continuous Process
The question of the beginning of life upon the earth had only to be satisfactorily answered for the establishment of the belief in a continuous process of evolution by natural law, even from the very beginning of the earth itself “without form and void,” until the production of the highest living organisms which it displays in our own time. And all ages, even by the mouths of their great thinkers and closest observers, had agreed in giving an apparently satisfactory answer to this question. It might well have been thought that Darwin was quite entitled to ignore altogether, as he did, the question of the origin of life. Everyone knew, so to say, that simple living organisms were every day evolved in organic refuse and elsewhere. Darwin himself, if we may judge from a casual remark in a letter, regarded the question apparently as purely speculative, and of small real moment. It is all rubbish, he says, thinking about the origin of life; we might as well argue about the origin of matter. We must beware of illegitimately attributing opinions to the immortal dead, but this remark, though a casual one, does seem to suggest that Darwin regarded these two questions as on all-fours, if not, indeed, as different forms of the same question, and that, if he had actually formulated his views, they would have taken the shape of the doctrine which asserts that life is implicit and potential in matter; in other words, that when suitable conditions arose—such, for instance, as the presence of liquid water—matter would display the properties of life.
An Abyss that could not be Bridged
Now, the remarkable fact—one of the most striking in the history of science—is that the time-honoured belief in spontaneous generation should have been attacked, and attacked with apparent success, just at the very time when it would otherwise have begun to assume real philosophic importance. For ages it had been accepted, taken as a matter of course, and not regarded as having any particular bearing upon the supreme questions. Then there came the time when this belief would have been an all-important link, without which the chain of evolution could not be completed, a link without which we were left to contemplate a perfect chain of inorganic evolution—the history of the earth before life—and a perfect chain of organic evolution—the history of life upon the earth, with an abyss between the two that could not be bridged, for how came life where there was no life? A series of experiments were made, experiments in which, strikingly enough, some of the greatest evolutionists of the day took a leading part, and these seemed to upset, just when it was most wanted by themselves for the establishment of their new doctrine, the belief which had gone without question for so many ages.
Is Life only Self-movement?
Now, some may be inclined to wonder how it should be that certain pioneers of the new doctrine of evolution, such as Tyndall and Huxley, should devote themselves with such persistence and labour and force to the overthrow of a doctrine which was so necessary for the complete establishment of their own case—so much so, that when they had overthrown it, they found themselves, as regards their own doctrine of evolution, placed in a difficulty from which they did not live to emerge. It is my own belief that this question can be answered, and the answer is of strict relevance to our present inquiry. I believe that Huxley and Tyndall were largely impelled by the desire to oppose a doctrine of the nature of life which was current in their time and is usually called “vitalism.” We shall not begin to understand the question of the beginning of life upon the earth, as that question may be legitimately stated to-day, unless we fully realise in what terms the doctrine of spontaneous generation was accepted in the past, and an understanding of this will teach us that the present-day revival of this doctrine presents it in a form very different from that which it so long held. Our discussion must be somewhat philosophic in character, but the question at issue is a highly philosophic one, and the reason why we have made so little progress in answering it hitherto is that men of science have too frequently discussed it without paying any serious attention to the profound philosophic questions which really underlie it. We have permitted ourselves to talk freely about life and matter, whilst claiming the right to take for granted the absolute validity of our conceptions of life and our conceptions of matter.
It was universally held by those, philosophic and simple, who also held throughout so many centuries the belief in spontaneous generation, that there is an overwhelming contrast between living and lifeless matter, and it was their belief in this overwhelming contrast that led them to give to the doctrine of spontaneous generation, as they held it, a form which cannot possibly be defended. The great character of life was conceived to be self-movement, this self-movement being displayed in the matter which composed the living organisms. But it was universally held that matter, as it was seen otherwise than in living organisms, was obviously and notoriously inert, gross, brute, and dead.
The Influence of Plato