August 2, 1906J 



NA TURE 



329 



appear in the circumstances described seem to be of a 

 nature identical with the minute bodies well known to 

 microscopists and recognised as crystals modified by a 

 colloid medium. They have been described by Kainey, 

 Harting, and Ord, on different occasions, many years ago. 

 They are not devoid of interest, but cannot be considered as 

 having any new bearing on the origin of living matter. 



Psychology. — 1 have given a special heading to this sub- 

 ject because its emergence as a definite line of experimental 

 research seems to me one of the most important features in 

 the progress of science in the past quarter of a century. 

 Thirty-five years ago we v.'ere all delighted by l-'echner'.s 

 psychophysical law, and at Leipzig 1, with others of my 

 day, studied it experimentally in the physiological labora- 

 tory of that gieat teacher, Carl Ludwig. The physiological 

 inethods of measurement (which are the physical ones) 

 have been more and more widely, and with guiding intelli- 

 gence and ingenuity, applied since those days to the study 

 of the activities of the complex organs of the nervous system 

 which are concerned with "mind" or psychic phenomena. 

 Whilst some enthusiasts have been eagerly collecting ghost 

 stories and records of human illusion and fancy, the serious 

 experimental investigation of the human mind, and its 

 forerunner the animal mind, has been quietly but steadily 

 proceeding in truly scientific channels. The science is still 

 in an early phase — that of the collection of accurate ob- 

 servations and measurements — awaiting the development of 

 great guiding hypotheses and theories. But much has been 

 done, and it is a matter of gratification to Oxford men that 

 through the liberality of the distinguished electrician, Mr. 

 Henry Wilde, F.R.S., a lectureship of Experimental 

 P.sychology has been founded in the University of Oxford, 

 where the older studies of Mental and Mora! Philosophy, 

 Logic and Metaphysics have so strong a hold, and have so 

 well prepared the ground for the new experimental develop- 

 ment. The German investigators W. Wundt, G. E. 

 Miiller, C. Stumpf, Ebbinghaus, and Munsterberg have 

 been prominent in introducing laboratory methods, and 

 have determined such matters as the elementary laws of 

 association and memory, and the perceptions of musical 

 tones and their relations. The work of Goldschneider on 

 ** the muscular sense,'* of von Frey on the cutaneous sensa- 

 tions, are further examples of what is being done. 



The difficult and extremely important line of investiga- 

 tion, first scientifically treated by Braid under the name 

 "Hypnotism," has been greatly developed by the French 

 school, especially by Charcot. The experimental investiga- 

 tion of " suggestion," and the pathology of dual conscious- 

 ness and such exceptional conditions of the mind, has been 

 greatly advanced by French observers. 



The older work of Ferrier and Hitzig on the functions of 

 the parts of the brain has been carried further by Goltz 

 and Munk in Germany, and by Schafer, Horsley, and Sher- 

 rington in England. 



The most important general advance seems to be the 

 realisation that the mind of the human adult is a social 

 product; that it can only be understood in relation with the 

 special environment in which it develops, and with 

 which it is in perpetual interaction. Prof. Baldwin, of 

 Princeton, has done important work on this subject. 

 Closely allied is the study of what is called " the psychology 

 of groups," the laws of mental action of the individual as 

 modified by his membership of some form of society. 

 French authors have done valuable work here. 



These two developments of psychology are destined to 

 provide the indispensable psychological basis for Social 

 Science, and for the anthropological investigation of mental 

 phenomena. 



Hereafter, the well-ascertained laws of experimental 

 psychology will undoubtedly furnish the necessary scientific 

 basis of the art of education, and psychology will hold the 

 same relation to that art as physiology does to the art of 

 medicine and hygiene. 



There can be little doubt, moreover, of the valuable inter- 

 action of the study of physical psychology and the theories 

 of the origin of structural character by natural selection. 

 The relation of the human mind to the mind of animals, 

 and the gradual development of both, is a subject full of 

 rich stores of new material, yielding conclusions of the 

 highest importance, which has not yet been satisfactorily 

 approached. 



NO. I 91 8, VOL. 74] 



1 am glad to be able to give wider publicity here to some 

 conclusions which I communicated to the Jubilee volume 

 of the " Soci(;li; de Biologic " of Paris in 1899. I there dis- 

 cussed the significance of the great increase in the size of 

 the cerebral hemispheres in recent, as compared with 

 ICocene Mammals, and in Man as compared with Apes, 

 and came to the conclusion that " the power of building 

 up appropriate cerebral mechanism in response to individual 

 experience," or what may be called " educability," is the 

 quality which characterises the larger cerebrum, and is 

 that which has led to its selection, survival, and further 

 increase in volume. The bearing of this conception upon 

 questions of 'fundamental importance in what has been 

 called genetic psychology is sketched as follows. 



" The character which we describe as ' educability ' can 

 be transmitted ; it is a congenital character. But the rcsuUs 

 of education can not be transmitted. In each generation 

 they have to be acquired afresh. With increased 

 ' educability ' they are more readily acquired and a larger 

 variety of them. On the other hand, the nerve-mechanisms 

 of instinct are transmitted, and owe their inferiority as 

 compared with the results of education to the very fact 

 that they are not acquired by the individual in relation to 

 his particular needs, but have arisen by selection of con- 

 genital variation in a long series of preceding generations." 



" To a large extent the two series of brain-mechanisms, 

 the 'instinctive' and the 'individually acquired,' are in 

 opposition to one another. Congenital brain-mechanisms 

 may prevent the education of the brain and the development 

 of new mechanisms specially fitted to the special conditions 

 of life. To the educable animal the less there is of 

 specialised mechanism transmitted by heredity, the better. 

 The loss of instinct is what permits and necessitates the 

 education of the receptive brain." 



" We are thus led to the view that it is hardly possible 

 for a theory to be further from the truth than that expressed 

 by George H. Lewes and adopted by George Romanes, 

 namely, that instincts are due to ' lapsed ' intelligence. The 

 fact is that there is no community between the mechanisms 

 of instinct and the mechanisms of intelligence, and that 

 the latter are later in the history of the development of the 

 brain than the former, and can only develop in proportion 

 as the former become feeble and defective.'" 



Darwinism. — Under the title " Darwinism " it is con- 

 venient to designate the various work of biologists tending 

 to establish, develop, or modify Mr. Darwin's great theory 

 of the origin of species. In looking back over twenty-five 

 years it seems to me that we must say that the con- 

 clusions of Darwin as to the origin of species by the 

 survival of selected races in the struggle for existence are 

 more firmlv established than ever. And this because there 

 have been 'many attempts to gravely tamper with essential 

 parts of the fabric as he left it, and even to substitute con- 

 ceptions for those which he endeavoured to establish, at 

 variance with his conclusions. These attempts must, I 

 think, be considered as having failed. A great deal of valu- 

 able work has been done in consequence ; for honest 

 criticism, based on observation and experiment, leads to 

 further investigation, and is the legitimate and natural 

 mode of increase of scientific knowledge. Amongst the 

 attempts to seriously modify Darwin's doctrine may be cited 

 that to assign a great and leading importance to Lamarck's 

 theory as to the transmission by inheritance of newly 

 " acquired " characters, due chiefly to American palaeontol- 

 ogists and to the venerated defender of such views, who 

 has now closed his long life of great work, Mr. Herbert 

 Spencer ; that to attribute leading importance to the action 

 of physiological congruity and incongruity in selective breed- 

 ing, which was put forward by another able writer and 

 naturalist who has now passed from among us. Dr. George 

 Romanes ; further, the views of de Vries as to discontinuity 

 in the origin of new species, supported by the valuable work 

 of Mr. Bateson on discontinuous variation ; and lastly, the 

 attempt to assign a great and general importance to the facts 

 ascertained manv years ago by the Abb^ Mendel as to the 

 cross-breeding of varieties and the frequent production (in 

 regard to cert.nin characters in certain cases) of pure strains 

 rather than of breeds combining the characters of both 

 parents. On the other hand we have the splendid series 



1 From the Jubilee volume of the Soc. de Biol, of Paris, 1899. Reprinted 

 in Nature, vol. Ixi., 1900, pp. 6?4, 625. 



