But, although in this passage there is this limitation, as a matter of fact there is a great deal more claimed by both writers for Evolution; for the title of Darwin’s book, “The Origin of Species,” shows very clearly that he applies his theory not merely to variations within species, but to the formation of the species within which these variations take place. I do not gather from his book that his theory goes so far as to suppose that either plants or animals have passed over from one species to another, both species being already in existence; but rather that through the power of “the struggle for existence,” “natural selection,” and “survival of the fittest,” existing races have been so changed and modified that new species have been evolved out of them, and that in every such evolution there has been what evolutionists consider to be improvement.
The arguments which Bishop Temple adduces for this theory are—
(1) “The unity of plan which can be found pervading any great class of animals seems to point to unity of ancestry.” [7c] He illustrates this by remarking that vertebrate animals are formed on a common plan.
(2) “Slight variations are perpetually being produced.” [7d]
(3) “The frequent occurrence both in plants or animals of useless parts which still remain as indications of organs that once were useful, and have long become useless.” [7e]
But is this scientific evidence? As to the 1st, the Bishop only claims for it that it “seems to point.” As to the 2nd, it quietly assumes the whole point at issue, for no one denies that there are variations “within each class or group,” and the fact that such variations exist within a certain class or group is no proof that they can extend beyond it. And as for the 3rd who knows that those that are called “useless parts” are really useless, though their use may not be known? And if they are useless now, what evidence is there that they were once useful, or were ever used? There is not the slightest scientific evidence in any one of these three points for the theory which they are adduced to support. There is not a single fact to prove the theory, and all that can be said by the most ardent advocate is that the conjecture seems to be probable. But how different is the evidence on the other side of the controversy! There we find certain clearly-defined and indisputable facts which cannot be doubted, and which cannot be reconciled with this new theory.
(1) Biological Evolution.
There cannot be a doubt that there are certain great classes of plants and animals found in the world, which have certain distinct characteristics, and which, as a matter of fact, do not merge into each other. There seems to be considerable variation in the names given to them, and they appear to be distinguished by the name sometimes of “species,” sometimes of “genus,” sometimes of “class or group,” and sometimes of “kind.” In the sentence quoted from Darwin on p. 6, he speaks of species, genera, and families; and describes them as being all descended each within its own class or group. This confusion of terms is difficult to reconcile with the boasted claim to scientific accuracy. That I may not be entangled by any questionable name I will distinguish these groups as A, B, C, D, etc., and our question is whether they have been evolved from each other or through each other, from a common stock; or whether they are separate creations. For the answer to this question let three facts be carefully considered.
(i.) There is the remarkable and clearly-established law of the sterility of all hybrids between any two of these great divisions. Both A and B may contain a great number of varieties, and all the varieties of A can breed freely with each other. In such case there is no failure of fertility in the progeny. The same is true of B and all the varieties that spring from it. If these varieties be expressed by the figures 1, 2, 3, etc., A1 may breed with A2, A3, or any other number, and so may introduce a fresh variety in the race A. But if A, or any variation of A, should breed with B, or any variation of B, there may be in the first instance a progeny; but there is a fixed and invariable law of nature that there should be no perpetuation of that progeny, for every individual so born is barren. Mules e.g., can never give birth to mules, and the mule race has no power of self-propagation. Now see how this bears on the subject of Evolution. If B were evolved out of A, there would, of course, be countless intermediate variations, and these variations would all have the power of perpetuating their kind. A would produce A1, A1 would produce A2, and so on, till A98 would produce A99, and, finally, to complete the series, A99 would produce A100, or B. But at this point, if the Evolution theory is to be reconciled with facts, a new and most strange law must be suddenly evolved; and the continuity of law must be broken. A98 may breed with A99, and their offspring may perpetuate their race; but if A99 should breed with A100, which is B, it is true there may be offspring, but that offspring will bare no power of self-perpetuation. How can evolutionism explain such a fracture in the continuity of law? And is not the scientific fact dead against the Evolution theory?
(ii.) As a matter of fact we do not find that continuous chain of intermediate links which the theory requires. The theory is, that as there are to be no sudden jumps in nature, the various numbers are evolved from each other in a vast series of almost imperceptible improvement; and it follows of necessity that, if the theory were true, instead of finding distinct classes, we should find various lines of progress stealing into each other in steps so minute that it would be very difficult to detect their differences. If, e.g., man has been evolved from monkey there ought not to be a yawning chasm, as there now is, between the two, but there ought to be a vast series of connecting links bridging the chasm between monkeyism and manhood; and there ought to be a race of monkeys still existing so near to man in physical structure and mental power that the birth of man from such a parentage should be within the range of natural probability. Let A be monkey, and B man, then there ought to be a continuous line of intermediate numbers, and A99 ought to approximate so closely to B that it would be perfectly natural for B to be its child.