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says, the tendency to vary diminishes, or ceases altogether. But that is really an argument for Darwin. The object of Darwin was not to show how the existing species may vary indefinitely from what they are at present, or have been within historic time, but to set forth to scientific thought how, in all probability, existing species have arisen. That the tendency to variation is great at first and gradually diminishes, may at once account for the production of specific differences, and for the fixity of species within historic time. Moreover, it tells in favour of the opinion that the organic process is controlled for cosmic ends, if the process is used for the creation of the world as we know it, but is not allowed to go on for its confusion. Another great objection which Professor Jenkin had against Darwin's doctrine was based on limitation of time. The modern discovery of the conservation of energy and the calculations of Sir William Thomson, have fixed the possible commencement of organic life upon our planet at far too recent a date for the purpose of the Darwinian. So said Professor Jenkin. But while, constrained by time limits, Professor Jenkin is willing to throw over an origination of species satisfactory to thought, he cannot bring himself to abandon the position of Lyell, that past geological changes must be explained by forces that act in the present. He gets out of the time difficulty by assuming that the geological forces were more rapid in their action in the primeval world than they are now. It never occurred to him, however, that it may have been the same with the causes which produced variations in animated beings. Yet there is his own earlier insistance on the fact that variation is rapid at first and gradually slows down till it ceases altogether. Is it unreasonable to suppose that in the primeval world, when, according to Sir William Thomson, the solar energy must have been far greater than it is now, variation may have gone on far more rapidly through organic beings sharing in the quickened life of the planet? Professor Jenkin's third great objection, that individual variation would be washed out by intercrossing, was more formidable when it was first urged than it is now. Darwin had no theory of variation. To him the struggle and progress rested on accidental variations in individuals, and hence he had no means of getting over the difficulty presented to his theory by intercrossing. Later science has supplied the defect in Darwin. Variation within certain limits is now shown to be an organic progress and no matter of accident. In similar conditions of existence, therefore, the variations would occur over a wider area, and not merely in scattered individuals. It is no longer the analogy of a single white man visiting an island, where his mulatto descendants are washed out by a few generations of intercrossing; but the invasion of a horde, whose issue will persist and permanently alter the breed of the island. Later investigators, without displacing Darwin's results, have thus carried the great argument further back into the question of the origin of variations. A most ingenious theory has lately been put forth by Professor Patrick Geddes, which, in the opinion of its author, affords us a higher natural ethic than can be got from Darwin. Whereas Darwin found a struggle at the root of the process, Professor Geddes finds that the dynamic is a species-regarding impulse. But I fail to see that a start from reproductive variations is speciesregarding in any other sense than is the Darwinian struggle. The first step in reproduction is, in the strictest biological sense, self-regarding. The mass of protoplasm, as it goes on nourishing itself, attains such a size that the outer surface is no longer large enough to furnish the needful nutriment to the mass within; for the outer surface increases in a less ratio than the mass. Either the mass must perish, or it must part in two and become a pair, in each of which the proportion between outer surface and inner mass will again be such as is needful for their continued life. And as at the start, so throughout the series of reproductive variations, each one of them is as much, in the biological sense, self-regarding as is the Darwinian struggle. If it is argued, they are species-regarding, because they result in the improvement of the species, so does the struggle result in the improvement of the species, and, in that sense, has a right to be called species-regarding too. I cordially agree with Professor Geddes, as against Professor Huxley, that nature is more to be regarded as a materialised ethical process than as a materialised intellectual process. I also welcome his beautiful theory of variation as an important and necessary basis for Darwinism. But the obligation to call in an ideal factor, or rather to see its presence, is as great in his theory of variation as it is in Darwin's theory of selection. With regard to the social instinct which reigns so mysteriously in certain species, the question is by no means settled yet, whether it is to be explained from below by the naturalist and physicist, or from above by the psychologist. Does it spring from purely physical causes, or has it an origin similar to that of the moral nature of man?
The full scope of the world's meaning can be seen only from a higher standpoint than Darwin himself could reach. But even at the point we have now attained we are able to see the great service rendered by Darwin's discovery. The pain of nature, the death of individuals, the disappearance of entire species to make room for others, was before an inexplicable mystery, and seemed to serve purpose accessible to our minds. But the law of natural selection is the key to the mystery. It shows nature in an aspect not unworthy of a wise and beneficent Ruler. Justice is dispensed from eon to eon in the spirit of the Holy Writing, “He that hath, to him shall be given; and from him that hath not, shall be taken even that which he seemeth to have.” The survival of the fittest has an ethical meaning, and fulfils a great ethical end. The facts of nature and the Darwinian theory of them, far from driving us to Professor Huxley's assumption of a non-moral intellectual ruling principle, carry in their heart a great moral principle which determines itself to an infinite development. To form a right conception of nature, we must take as centre the great moral idea which permeates the whole, reigns unconsciously in the inorganic and in the lower organic