But here, again, comes the difficulty of saying what Professor Weismann does, and what he does not, dispute. One moment he gives all that is wanted for the Lamarckian contention, the next he denies common-sense the bare necessaries of life. For a more exhaustive and detailed criticism of Professor Weismann’s position, I would refer the reader to an admirably clear article by Mr. Sidney H. Vines, which appeared in Nature, October 24, 1889. I can only say that while reading Professor Weismann’s book, I feel as I do when I read those of Mr. Darwin, and of a good many other writers on biology whom I need not name. I become like a fly in a window-pane. I see the sunshine and freedom beyond, and buzz up and down their pages, ever hopeful to get through them to the fresh air without, but ever kept back by a mysterious something, which I feel but cannot either grasp or see. It was not thus when I read Buffon, Erasmus Darwin, and Lamarck; it is not thus when I read such articles as Mr. Vines’s just referred to. Love of self-display, and the want of singleness of mind that it inevitably engenders—these, I suppose, are the sins that glaze the casements of most men’s minds; and from these, no matter how hard he tries to free himself, nor how much he despises them, who is altogether exempt?
Finally, then, when we consider the immense mass of evidence referred to briefly, but sufficiently, by Mr. Charles Darwin, and referred to without other, for the most part, than off-hand dismissal by Professor Weismann in the last of the essays that have been recently translated, I do not see how any one who brings an unbiased mind to the question can hesitate as to the side on which the weight of testimony inclines. Professor Weismann declares that “the transmission of mutilations may be dismissed into the domain of fable.” [38] If so, then, whom can we trust? What is the use of science at all if the conclusions of a man as competent as I readily admit Mr. Darwin to have been, on the evidence laid before him from countless sources, is to be set aside lightly and without giving the clearest and most cogent explanation of the why and wherefore? When we see a person “ostrichising” the evidence which he has to meet, as clearly as I believe Professor Weismann to be doing, we shall in nine cases out of ten be right in supposing that he knows the evidence to be too strong for him.
THE DEADLOCK IN DARWINISM—PART III
Now let me return to the recent division of biological opinion into two main streams—Lamarckism and Weismannism Both Lamarckians and Weismannists, not to mention mankind in general, admit that the better adapted to its surroundings a living form may be, the more likely it is to outbreed its compeers. The world at large, again, needs not to be told that the normal course is not unfrequently deflected through the fortunes of war; nevertheless, according to Lamarckians and Erasmus-Darwinians, habitual effort, guided by ever-growing intelligence—that is to say, by continued increase of power in the matter of knowing our likes and dislikes—has been so much the main factor throughout the course of organic development, that the rest, though not lost sight of, may be allowed to go without saying. According, on the other hand, to extreme Charles-Darwinians and Weismannists, habit, effort and intelligence acquired during the experience of any one life goes for nothing. Not even a little fraction of it endures to the benefit of offspring. It dies with him in whom it is acquired, and the heirs of a man’s body take no interest therein. To state this doctrine is to arouse instinctive loathing; it is my fortunate task to maintain that such a nightmare of waste and death is as baseless as it is repulsive.
The split in biological opinion occasioned by the deadlock to which Charles-Darwinism has been reduced, though comparatively recent, widens rapidly. Ten years ago Lamarck’s name was mentioned only as a byword for extravagance; now, we cannot take up a number of Nature without seeing how hot the contention is between his followers and those of Weismann. This must be referred, as I implied earlier, to growing perception that Mr. Darwin should either have gone farther towards Lamarckism or not so far. In admitting use and disuse as freely as he did, he gave Lamarckians leverage for the overthrow of a system based ostensibly on the accumulation of fortunate accidents. In assigning the lion’s share of development to the accumulation of fortunate accidents, he tempted fortuitists to try to cut the ground from under Lamarck’s feet by denying that the effects of use and disuse can be inherited at all. When the public had once got to understand what Lamarck had intended, and wherein Mr. Charles Darwin had differed from him, it became impossible for Charles-Darwinians to remain where they were, nor is it easy to see what course was open to them except to cast about for a theory by which they could get rid of use and disuse altogether. Weismannism, therefore, is the inevitable outcome of the straits to which Charles-Darwinians were reduced through the way in which their leader had halted between two opinions.
This is why Charles-Darwinians, from Professor Huxley downwards, have kept the difference between Lamarck’s opinions and those of Mr. Darwin so much in the background. Unwillingness to make this understood is nowhere manifested more clearly than in Dr. Francis Darwin’s life of his father. In this work Lamarck is sneered at once or twice, and told to go away, but there is no attempt to state the two cases side by side; from which, as from not a little else, I conclude that Dr. Francis Darwin has descended from his father with singularly little modification.
Proceeding to the evidence for the transmissions of acquired habits, I will quote two recently adduced examples from among the many that have been credibly attested. The first was contributed to Nature (March 14, 1889) by Professor Marcus M. Hartog, who wrote:—
“A. B. is moderately myopic and very astigmatic in the left eye; extremely myopic in the right. As the left eye gave such bad images for near objects, he was compelled in childhood to mask it, and acquired the habit of leaning his head on his left arm for writing, so as to blind that eye, or of resting the left temple and eye on the hand, with the elbow on the table. At the age of fifteen the eyes were equalised by the use of suitable spectacles, and he soon lost the habit completely and permanently. He is now the father of two children, a boy and a girl, whose vision (tested repeatedly and fully) is emmetropic in both eyes, so that they have not inherited the congenital optical defect of their father. All the same, they have both of them inherited his early acquired habit, and need constant watchfulness to prevent their hiding the left eye when writing, by resting the head on the left forearm or hand. Imitation is here quite out of the question.
“Considering that every habit involves changes in the proportional development of the muscular and osseous systems, and hence probably of the nervous system also, the importance of inherited habits, natural or acquired, cannot be overlooked in the general theory of inheritance. I am fully aware that I shall be accused of flat Lamarckism, but a nickname is not an argument.”
To this Professor Ray Lankester rejoined (Nature, March 21, 1889):—