ARE ACQUIRED POWERS TRANSMITTED TO DESCENDANTS ?*
Tins is an interesting little book, rather baldly written, and not made nearly so interesting as it might have been, had Mr. Ball discussed more fully the mental transmission or non- transmission of highly improved faculties, a subject on which he contents himself with general references to Mr. Francis Gallen. Mr. Ball's position is that only those variations of physique and character which are born with a man are transmitted to his descendants, and that the increment which he gains by careful use and practice is not so transmitted. To take an illustration, he would hold that an athlete, so far as he is gifted originally with any special alertness for the use of his limbs and with any special muscular provisions, will in all probability transmit those capacities to one or more of his descendants, but that even a Blondin will not transmit more capacity of this kind to the descendants of his maturest years, than he would to the descendants of his early youth; that the simple and compound interest, as it were, which he gains by practice and habit dies with him, and is not transmissible to his posterity ; and so, too, of course, that the oratorical or histrionic faculty, or any other faculty, so far as it is an inheritance from parents, is liable to be transmitted to descendants, but so far as it arises from cultivation and constant use and polishing, is not so trans- missible. This is the view of Weismann and of several considerable modern physiologists, and at first sight it seems to be a somewhat paradoxical view; for how, it will be asked, do races of men become civilised at all, if none of the acquired civility of their lives under good civil rule is transmitted to their offspring ? In that case, it will be said, there would be no reason why a race which had been under civilising influence for two thousand years should not produce children as full of savage instincts as cannibals or Australian natives. But this is evidently a gross misreading of the view. It is not held that the habits and customs of civilised races produce no effect on the type of those who survive, but only that they produce no effect on it by direct inheritance. They do produce a great effect on it by rendering those born with larger brain-power, and less of animal ferocity, more likely to prosper than those who are born with smaller brain-power and more of animal ferocity. Amongst Greeks, for • Are the Effects of Die and Disuse Inherited f An Examination of the View held by Spencer and Darwin. By William Platt Ball. London: Macmillan and Do. instance, of the earliest period of Greece, there must have been far better prospects for a man of founding a family that would last and prosper, if he had quickness of mind, imagination, address, vision, geniality, and considerable power of expres- sion, than there would have been if he had been born with nothing but strong limbs and hot passions. It is not main- tained that the acquired intellectual and moral culture of a race does not tend to survive, but only that it does not tend to survive through direct inheritance, but rather by imposing the conditions which render men born with these higher quali- ties in consequence of the happy combination of the qualities of their parents, more likely to survive, and those born without. these intellectual and moral aptitudes, more likely to die out. Of course, if it is easy to imagine one savage born with a larger power of thought and self-control than another, with- out the inheritance of any acquired habit, it is easy to imagine that the same variations might take place age after age, the acquired habits of a civilised society only tending to promote the preservation and multiplication of those who inherit such qualities, even though that which special individuals have acquired be not transmitted to their descendants. Mr. Ball puts his case very well when he discusses the tameness of domesticated rabbits, in reply to Darwin's view,—indeed, we think that he puts his ease better in that section of his little book than he puts it anywhere else :— " Darwin holds that in some cases selection alone has modified the instincts and dispositions of domesticated animals, but that in most cases selection and the inheritance of acquired habits have concurred in effecting the change. On the other hand,' he says, `habit alone in some cases has sufficed; hardly any animal is more difficult to tame than the young of the wild rabbit ; scarcely any animal is tamer than the young of the tame rabbit; but I can hardly suppose that domestic rabbits have often been selected for tameness alone ; so that we must attribute at least the greater part of the inherited change from extreme wildness to extreme tameness to habit and long-continued close confinement.' But there are strong, and to me irresistible, arguments to the contrary. I think that the following considerations will show that the greater part, if not the whole, of the change must be attributed to selection rather than to the direct inheritance of acquired habit. (1.) For a period which may cover thousands of generations, there has been an entire cessation of the natural selection which maintains the wildness (or excessive fear, caution, activity, &c.) so indispensably essential for preserving defenceless wild rabbits of all ages from the many enemies that prey upon them. (2.) During this same extensive period of time man has usually killed off the wildest and bred from the tamest and most manageable. To some extent he has done this consciously. ' It is very conducive to successful breeding to keep only such as are quiet and tractable,' says an authority on rabbits, and he enjoins the selection of the hand- somest and best-tempered does to serve as breeders. To a still greater extent man has favoured tameness unconsciously and indirectly. He has systematically selected the largest and most prolific animals, and has thus doubled the size and the fertility of the domestic rabbit. In consciously selecting the largest and most flourishing individuals and the best and most prolific mothers, he must have unconsciously selected those rabbits whose relative tameness or placidity of disposition rendered it possible for them to flourish and to produce and rear large and thriving families, instead of fretting and pining as the wilder captives would do. When we consider how exceedingly delicate and easily disturbed yet all-important a function is that of maternity in the continually breeding rabbit, we see that the tamest and the least terrified would be the most successful mothers, and so would con- tinually be selected, although man cared nothing for the tame- ness in itself. The tamest mothers would also be less liable to neglect or devour their offspring, as rabbits commonly do when their young are handled too soon, or even when merely frightened by mice, &c., or disturbed by changed surroundings. (3.) We must remember the extraordinary fecundity of the rabbit and the excessive amount of elimination that consequently takes place either naturally or artificially. Where nature preserved only the wildest, man has preserved the tamest. If there is any truth in the Darwinian theory, this thorough and long-continued reversal of the selective process must have had a powerful effect. Why should it not be amply sufficient to account for the tameness and. mental degeneracy of the rabbit without the aid of a factor which can readily be shown to be far weaker in its normal action than either natural or artificial selection ? Why may not the tameness- of the rabbit be transferred to the group of cases in which Darwin holds that 'habit has done nothing,' and selection has done all P (4.) If use-inheritance has tamed the rabbit, why are the bucks still so mischievous and unruly ? Why is the Angora breed the. only one in which the males show no desire to destroy the young P Why, too, should use-inheritance be so much more powerful in the rabbit than with other animals which are far more easily tamed in the first instance ? Wild young rabbits when domesti- cated ' remain unconquerably wild,' and, although they may be kept alive, they pine and 'rarely come to any good.' Yet the animal which acquires least tameness—or apparently, indeed, none at all—inherits most ! It appears, in fact, to inherit that which it cannot acquire—a circumstance which indicates the selection of spontaneous variations rather than the inheritance of changed habits. Such variations occasionally occur in animals in a marked. degree. Of a litter of wolf-cubs, all brought up in the same way, 'one became tame and gentle like a dog, while the others pre- served their natural savagery.' Is it not probable that permanent domestication was rendered possible by the inevitable selection of spontaneous variations in this direction P The excessive tameness, too, of the young rabbit, while easily explicable as a result of unconscious selection, is not easily explained as a result of acquired habit. No particular care is taken to tame or teach or domesticate rabbits. They are bred for food, or for profit or appearance, and they are left to themselves most of their time. As Sir T. Sebright notices with some surprise, the domestic rabbit is not often visited, and seldom handled, and yet it is always tame.' " Undoubtedly Mr. Ball shows that the evidence for the trans- mission of acquired and uninherited faculty is very weak and
uncertain, and he even maintains that if the inheritance of acquired powers were common, men would soon become very top-heavy creatures, the rope-dancer's children being mostly born rope-dancers, the pleader's children mostly born pleaders, and so forth, until we had got a system of caste so intolerably close-welded, that the human race would hardly be a single race at all.
The present reviewer is not competent to estimate the exact value of Mr. Platt Ball's argument as disproving the inheritance of the acquired as distinct from the inherited element in human. power. But undoubtedly Mr. Ball does show that the argument for such an inheritance is very much weaker than it is ordinarily supposed to be, and that there is nothing like the same probability that acquired power will be in- herited by some of the posterity, that there is that the inherited
power will be transmitted. Unquestionably the most efficient way in which the acquired habits of society influence the next
generation is by affecting the conditions of natural selection, not by direct transmission. The acquired habits and notions determine what kind of character shall succeed and what shall fail, but they are hardly ever transmitted in sufficient force to prove that the acquisitions of one generation are the innate talents of the next.
But if this be so, the most important aspect of Mr. Platt Ball's little book is its bearing,—which he passes over,— on the philosophy which asserts that the innate ideas, as they used to be called,—the innate forms of thought and feeling, as we should prefer to call them,—are the mere gradual deposits of thousands of generations of habitual association. This is, as is well known, Mr. Herbert Spencer's explanation of necessary truths, whether mathematical or moral; he thinks them the mere growth of habitual experi- ence, and would suppose, we imagine, that if we could in- terrogate our ancestors of four thousand or ten thousand years ago, we should find that their conceptions of what we now call " necessary" truth were by no means necessary, but were only beginning to impress men as probable, and more or less plausible. If, however, each generation derives directly
from its predecessor only what that predecessor had derived, plus the fresh bias towards intellectual and moral views of life, which each generation in its turn expresses by favouring the more cultivated, and depressing the more animal type of
character, Mr. Spencer's explanation of necessary truth as the gradually accumulated experience of thousands and thousands of years of steady association, vanishes at once. For the contrast remains as marked as ever between the teaching of uniform experience which we can nevertheless easily suppose different, like the uniform succession of sunrise and sunset, and
the necessary truths which we cannot even suppose altered, each as that two straight lines cannot enclose a space, or that two sides of a triangle are together greater than the third.
Hence we are left with as powerful an argument against the piecemeal evolution of mathematical and logical and moral truth, as we had before the Spencerian psychology was given to the world.
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