Februarv 27, 1908J 



NATURE 



391 



consequent cutting off of the " trophic influeiicc " exer- 

 cised by the latter. 



Again, it is a part of Mr. Reid's doctrine, as he tells 

 us, to regard the power of walking and the power of 

 speaking as use acquirements, while I, on the contrary, 

 hold that the effects of use-exercise seem to be predominant 

 in these cases simply because the efforts made to walk or 

 to talk take place pari passu with the development of the 

 nerve centres concerned with such accomplishments. 



As I have said elsewhere (" The Brain as an Organ of 

 Mind," p. 5()2), "the helpless condition of the infant 

 monkey and of the human infant at birth are similarly to 

 be ascribed, in great part, to the immature condition of 

 their great nerve centres. Many of the movements which 

 they slowly learn to perform are doubtless rendered possible 

 by, and acquired coincidently with, the actual development 

 of those nerve cells and fibres in the spinal cord and 

 medulla U'/iiV/i are instrumental in the execution of such 

 movements. Thus, when we say that the young child 

 ' learns ' to perform these movements, it should be under- 

 stood that this word is here applicable only in a very 

 qualified sense. . . . But for the existence of this organic 

 nisus (in the form of an inherited tendency to develop in 

 certain modes and directions) the human infant could never 

 so readily as it does acquire the power of executing the 

 excessively complex movements which are concerned in 

 standing, in walking, or in articulate speech." 



In illustration of these views I have cited cases in which 

 walking was an untaught act in a child at the end of 

 her second year, as there had been no previous trials and 

 failures; and also a case {loc. cit., p. 607) in which a 

 child who had been absolutely dumb up to the end of his 

 fifth year suddenly began to speak under an emotional 

 stimulus. Another very similar modern case, as well as 

 two cases recorded by ancient writers, of untaught acts 

 of speech are also cited in my work on " .\phasia and 

 other Speech Defects " (1898, pp. 6-8). 



No explanation of such facts seems possible except on 

 the supposition that speech has now become a truly auto- 

 matic act for human beings. Such untaught acts of speech 

 would not, however, be possible unless cerebral develop- 

 ment had been taking place in a normal manner, and 

 unless the auditory sense and intelligence were unaffected. 



These are some of the reasons why I dissent from Mr. 

 Reid's view that " in man the main difference between the 

 infant and the adult is due to use acquirements made by 

 the latter during development," and why I say that post- 

 natal growth and development are essentially due to the 

 same Inherent causes as pre-natal growth, notwithstanding 

 the fact that use-exercise comes in as a powerful aid 

 during the former period. 



.As to the extraordinary power of memorising shown by 

 Chinese and Mohammedan children to which I referred 

 Mr. Reid, in accordance with his views he would deny 

 that any influence is to be ascribed to the practice in 

 memorising carried on by ancestors of the children through 

 verv many previous generations ; and in that case he 

 must suppose that English children, as a class, should be 

 capable of showing similar feats of memory, even though 

 their ancestors had not been accustomed to any extra- 

 ordinary exercise of their memorial faculty. 



For the rest, that Mr. Reid's views do not suffice to 

 close the controversy as to the inheritance of " acquired " 

 characters mav be easily seen by any of your readers who 

 will refer to Herbert Spencer's "Principles of Biology," 

 revised edition, iSoS, App. C, pp. 602-695. and to his 

 " Facts and Comments," 1902, pp. 92-96. I might even 

 venture to refer your reviewer, "A. D. D.," to a con- 

 sideration of the facts and arguments set forth in these 

 ■works. H. Charlton B.\sti.\s. 



The ."Vthen^um, London, February 15. 



I SAID that acquirements are just as " innate " as " in- 

 horn " characters. Dr. Bastian read this — I am sure I 

 cannot imagine why — as implying a denial of the occur- 

 rence of variations. I repudiated his interpretation, and 

 this he now terms an admission ! The muscles of a limb 

 atrophy equally when they are rendered useless by joint 

 disease as when there is " severance between the limb 

 and the great nerve centres." 



NO. 2000, VOL. 77] 



The Lamarckian doctrine is founded on two unproved 

 assumptions : — (i) that use causes development in all 

 characters, and (2) that parental acquirements tend to 

 affect the germ-cells in such a way that the traits which 

 arise in the parent under the stimulus of use are repro- 

 duced by offspring under the stimulus of nutriment — that 

 is, when the parent acquires one thing the child is sup- 

 posed to " inherit " something inherently different and 

 much less useful. The second assumption was formerly 

 universal, but has now been abandoned by the vast 

 majority of biologists. Most of us know, or think we 

 know, how great an obstacle it was to the attainment of 

 truth and how much deeper and clearer has become our 

 knowledge of nature since its abandonment. We suppose it 

 was held merely because men tend to accept current beliefs 

 without bestowing on them that critical and sceptical 

 thought which is one of the essentials of real scientific work. 



The first assumption is still very generally made, and 

 I think for the same reason. Unsupported by an iota of 

 evidence and obscuring the fact that a principal feature of 

 the evolution of the higher animals has been the evolution 

 of a power of developing under the stimulus of use, it is 

 as great an obstacle to the recognition of truth as the 

 other. Many human structures are plainly incapable of 

 developing under the stimulus of use, for example, hair, 

 teeth, external ears, and memory. These are wholly " in- 

 born " (i.e. developed under the stimulus of nutrimentV 

 The evidence seems massive that many lower animals, for 

 example, the Coleoptera and Lepidoptera, owe little or no 

 part of their physical and mental development to use. 

 Hence their lack of individual adaptability. But higher in 

 the animal scale, memory (the power of profiting by mental 

 experience, of growing mentally under the stimulus of use) 

 becomes apparent, and increases until it bestows on man 

 all that makes him preeminently the educable, rational, 

 and adaptable being. Pari passti with this increase of the 

 power of growing mentally under the stimulus of use has 

 occurred an equally great evolution of the power of grow- 

 ing physically under the same stimulus. In my view, 

 then, (i) while memory and the homologous power of 

 growing physically are " inborn," all that arises from the 

 exercise of them is "acquired"; (2) not all human 

 characters are capable of developing under the stimulus 

 of use, but only a majority of them ; and (3) in the case 

 of the latter ail, or nearly all, that separates the infant 

 from the adult is due to the stimulus of use. 



Either Dr. Bastian is putting the cart before the horse or 

 I am. I believe, for example, that use develops body and 

 mind until we are able to walk, talk, and so forth. He 

 believes, apparently, that we would develop physically and 

 mentally into mature men, and would walk and talk and get 

 a knowledge of Latin and so on even if we never used body 

 and mind. The blessed words " trophic influences " and 

 " organic nisus " afford him complete satisfaction. Surely 

 his assumption is made " in the face of multitudinous 

 difficulties." To him man's adaptability, the vastness of 

 his memory, the great development in him of the instincts 

 of sport, curiosity, and imitativeness, which impel him to 

 make precisely the physical and mental acquirements which 

 bring him into harmony with his own individual environ- 

 ment, tell no tale. He is in a position as unhappy as 

 those investigators who. before defining what they mean 

 bv " inheritable." spend years of labour in ascertaining 

 exactiv what is " inherited." 



Mr. Cunningham says, " innate characters are those 

 which develop without any stimulus except what Dr. Reid 

 calls the stimulus of nutrition." or nutriment as I prefer 

 to term it. But is not nutriment "external"? A scar 

 cannot develop under this stimulus, and I imagine it would 

 nuzzle Mr. Cunningham to explain in what sense nutriment 

 is more innate than injury or use. Obviously all characters 

 develop under the influence of some external stimulus, and 

 the distinctions between characters are due, not to greater 

 or lesser innateness, but to the kinds of stimuli that cause 

 them to appear. Acquirements arise for precisely the same 

 reason that all inborn characters arise — because evolution 

 has created the power of responding in quite definite ways 

 to quite definite external stimuli ; clearly, then, they are 

 innate in precisely the same sense as inborn characters. 



Februarv 21. G. Archdall Reid. 



