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SCIENCE 



[Vol. XVII. No. 430 



been added. These two defects will seriously binder the service 

 of the "Outlines," as they have of the "Elements." The facts 

 which the beginner in psychology and the general reader alike 

 need and desire, are the chief facts of modern scientific psychology 

 in all its various departments. What is here termed "physiologi- 

 cal psychology " is but a somewhat arbitrarily selected portion of 

 that general body of knowledge. And within the field covered we 

 find the same disproportion among the topics. The preliminary 

 portion on the nervous system and the functions of the brain cer- 

 tainly occupies too much space- for so elementary a work. 



There is, too, a lack of vitality in certain portions of the work, — 

 something that gives the student the impression that he is dealing 

 with reports of papers and personal news, and not with facts and 

 •Iheir interpretation. This defect is less marked in the newer 

 work. It, too, has the advantage of benefiting by the more recent 

 studies and the criticisms directed against the " Elements." While 

 regretting these defects, we may none the less cordially recom- 

 mend these volumes as an important and interesting means of 

 approach to an important and interesting subject. 



Animal Life and Intelligence. By C. Lloyd Morgan, F.G.S. 

 Boston, Ginn. 



One of the dominant characteristics of naodern English science 

 is the attention devoted to the study of mental phenomena from a 

 general biological point of view ; the application of the compara- 

 tive method, under the guidance of the principle of evolution, to 

 the various activities contributing to and conditioning life, both 

 bodily and mental. In so far as there exists a school of scientific 

 psychologists in England, this is the common principle of their 

 unity. A majority of the best known of modern English psy- 

 chologists are men with a thorough and generally a professional 

 biological training, who view the study of mind as a factor, and 

 a most important and indicate one, in the general series of ac- 

 tions and re-actions of which life consists. It need hardly 

 ■ be said that in so doing they are continuing along the path so 

 splendidly opened out by Darwin. It is to this school of thinkers 

 that Mr. Morgan belongs ; it is to this phase of psychology, or, if 

 you prefer, biology, that the present work is devoted. The car- 

 dinal position of the work maintains the necessity of studying 

 mind as a part of life, of studying it comparatively, of explain- 

 ing, classifying, and studying mental phenomena by their purpose 

 and significance in the natural, the biological world. 



As the title implies, the work is divided into two portions, — 

 the one setting forth the phenomena of animal life, the other deal- 

 ing more particularly with those functions of life in which intelli- 

 gence is involved ; and it is extremely convenient to have so able 

 a treatment of both topics between the same covers. For the 

 student or the general reader whose aim it is to secure by the 

 reading of a single book some insight into those central problems 

 of biology, life, and intelligence, Mr. Morgan's is the book to be 

 recommended. It is not an exhaustive treatment, but the selec- 

 tion of topics is according to the centres of most vital interest; and 

 the treatment is aUvays judicious, many-sided, interesting, and 

 clear. After a general description of the qualities by which the 

 •organic is differentiated from the inorganic, and of the more im- 

 portant of the processes by which an individual life is maintained, 

 Tuns the cycle of its life-history, and leaves its offspring to per- 

 petuate the species, we are introduced to the kernel of modern 

 biology, the relation of life to the environment. This portion of 

 the work is considered under the heads of " Variation and Natu- 

 ral Selection," " Heredity and the Origin of Variations," and 

 -"Organic Evolution." While much of the contents of these 

 -chapters is mainly expository, and thus admits of originality or 

 peculiarity mainly in the mode of treatment, the disputed points 

 in modern biology are by no means avoided, and both sides of the 

 case are always given. Chief among these disputed points is the 

 one over which the biological camps are so sharply divided, — the 

 inheritance of acquired characteristics. Mr. Morgan admirably 

 states the importance of this issue, and returns to the problem 

 again and again. He instructively as well as amusingly discusses 

 the issue by considering whether " the hen produces the egg" or 

 '' the egg produces the hen." The Weismann view, which denies 

 *he inheritance of the influences of individual environment, would 



hold that " the egg produces the hen," and the parent egg is con- 

 nected with the young egg, each developing to maturity under its 

 own conditions; while, under the opposite view, "the hen pro- 

 duces the egg," that is, the egg is the offspring of the mature 

 hen, modified since birth by a host of environmental accidents 

 and conditions. Mr. Morgan's final position, reac'ned by dint of 

 much balancing and consideration, may be gathered fx-om the 

 following words: "Now, although I value highly Professor 

 Weismann's luminous researches, and read with interest his ingen- 

 ious speculations, I cannot but regard his doctrine of the conti- 

 nuity of germ-plasm as a distinctly retrograde step.'' So, too, in 

 the mental world Mr. Morgan regards the hypothesis of the non-in- 

 heritance of acquired characteristics as untenable, though he fully 

 admits the absence of crucial cases, and the possibility of interpreta- 

 tion of many facts from both points of view. In his final chapter 

 be deduces from Professor Weismann's views the conclusion that 

 education, " though it may raise the level of each generation, can 

 have no cumulative effect ; " that the diffusion of knowledge 

 brings more grist to the mQl but doesn't improve the mill, increases 

 the store of food but not the powers of the digestive apparatus; 

 and, in opposition to this view, it is held that the rise in the in- 

 tellectual level of Englishmen of to-day, as compared with those 

 of the days of the Tudors, has been in part due to the inheritance 

 of individually acquired faculty." 



Mr. Morgan's views on other of the factors and processes of 

 organic evolution possess many points of interest and individual- 

 ity, but it is impossible to do more than mention their existence 

 in this connection. Some of the points which he emphasizes may 

 be inferred from the following citation: "First, we should be 

 careful not to use the phrase ' of advantage to the species ' vaguely 

 and indefinitely, but should in all cases endeavor clearly to indi- 

 cate wherein lies the particular advantage, and how its possession 

 enables the organism to escape elimination; next, we must re- 

 member that the advantage must be immediate and present, pro- 

 spective advantage being, of course, inoperative; then we must 

 endeavor to show that the advantage is really sufficient to decide 

 the question of elimination or non-elimination; lastly, we must 

 distinguish between indiscriminate and differential destruction, 

 between mere numerical reduction by death or otherwise and 

 selective elimination." 



Entering now upon the more strictly psychological portion of 

 the work, we meet first with a very clear and interesting account of 

 the realm of sensation in the animal world. The keynote of the 

 exposition is that the activity of a sense-organ must be accounted 

 for by the utility of this mode of response to the environment 

 in the struggle for existence. The fallacy of insisting upon an ex- 

 act parallelism between human senses and those of animals is also 

 strongly stated. The ground covered in the chapter upon 

 " Mental Processes in Man" is familiar. It consists in the main 

 of the description of the various processes involved in sensation, 

 perception, inference, and the like. The two points most strongly 

 insisted upon are that the relation to our environment involves 

 the two factors of subject and object, of the mind that perceives 

 and the things perceived; and that we must distinguish between 

 the perceptual and the conceptual powers, the latter involving 

 analysis and to some extent abstraction and consciousness. In 

 attempting to study the resemblances and differences between 

 human and animal intelligence, we must beware of endowing the 

 animal with human points of view. The similarity of sense data 

 is no guaranty for a similarity of mental perception and elabora- 

 tion. In illustration of our tendency to neglect the ignorance of 

 animals, there is cited Mr. Hamerton's story of the cow which 

 was quieted by having the stuffed body of her dead calf to lick, 

 and which, when accidentally tearing open the skin and seeing 

 the hay inside, devoured the unexpected provender without 

 showmg the slightest surprise. But the surprise is only for us 

 acquainted with anatomy: it is no incongruity to the cow, which 

 indeed, having experience of "putting hay inside," not Ulogically 

 expects to find hay there. We each construct our world, and 

 how different the constructive powers in the two cases ! In the 

 description of instances of animal intelligence, which naturally 

 find considerable place in the work, the analysis proceeds along a 

 psychological basis, the degree of mental power being measured by 



