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THURSDAY, SEPTEMBER 7, i5 



ANIMAL INTELLIGENCE 

 Animal Intelligence. By George J. Romanes, M.A., 

 LL.D., F.R.S., Zoological Secretary to the Linnean 

 Society. International Scientific Series. (London : 

 Kegan Paul, Trench, and Co., 1882.) 



THE psychology of animals having hitherto been 

 treated only in detached portions, and for the most 

 part in an uncritical manner, Dr. Romanes has " thought 

 it desirable that there should be something resembling a 

 text-book of the facts of comparative psychology, to which 

 men of science, and also metaphysicians, may turn when- 

 ever they may have occasion to acquaint themselves with 

 the particular level of intelligence to v hich this or that 

 species of animals attains." But this is only one of the 

 objects with which he has undertaken the treatment of 

 the psychology of animals. The second and more im- 

 portant object "is that of considering the facts of animal 

 intelligence in their relation to the theory of Descent." 

 The present volume supplies the basis for this mode of 

 considering the facts. " While complete in itself as a 

 statement of the facts of Comparative Psychology," it is 

 preliminary to a second division of the work, which is to 

 be brought out as a separate treatise under the title of 

 "Mental Evolution." 



Since the present volume is to be regarded as the first 

 part of a scientific treatise, it is, of course, important that 

 we should know the critical principles on which the facts 

 have been selected. Dr. Romanes has stated these in 

 his preface. It will not be denied that his canons of 

 criticism are sufficiently severe ; and in the book itself 

 we do not receive that impression that the facts are being 

 described without careful discrimination, which often 

 makes itself felt in reading collections of anecdotes about 

 animals. But, considering the possibilities of the subject, 

 most readers will look for descriptions which may be 

 scientifically accurate or not, but which, in either case, 

 are interesting in themselves. And, notwithstanding the 

 intention he has expressed, "as far as the nature and cir- 

 cumstances of the inquiry would permit, to suppress 

 anecdote," Dr. Romanes has written a book that is very- 

 pleasant to read. Besides this, the materials are arranged 

 in such a way that there is no difficulty in finding any fact 

 that it is desired to refer to. 



Dr. Romanes points out more than once " how slightly 

 a psychological classification of animals depends upon 

 zoological affinity, or even morphological organisation " 

 (p. 241). The zoological classification is followed for the 

 sake of its convenience, but at the same time it has, of 

 course, been found necessary to treat some groups in 

 much more detail than others. " Anatomically, an ant 

 or a bee does not require more consideration than a 

 beetle or a fly ; but psychologically there is need for as 

 great a difference of treatment as there is in the not very 

 dissimilar case of a monkey and a man " (Preface, x.). 

 As an example of the mode of classifying the facts relating 

 to each group, the chapter on Ants may be referred to. 

 First the researches are described that have been made 

 in order to determine the exact character of the special 

 senses of ants, and of the " sense of direction." After 

 Vol. xxvi.— No. 671 



this, the powers of memory and recognition are con 

 sidered, then the emotions. Then follow sections on the 

 powers of communication, the habits, and the general 

 intelligence of ants. Lastly, there is a short section on 

 the nervous system and the sense organs ; but this is not 

 represented in the chapters dealing with other animals. 



Though the complete theoretical treatment of mental 

 phenomena in animals does not belong to the present 

 volume, yet there is in the Introduction some discussion 

 of theoretical questions. This was indeed necessary in 

 order to arrive at a provisional mode of grouping the 

 facts. For it has been objected to those who speak of 

 the " emotions " of an ant or a bee, for example, that we 

 are not justified in applying terms derived from human 

 psychology to animals so remote in structure from the 

 human type. Dr. Romanes replies to this objection by 

 showing that the ground of all inferences as to the mental 

 processes of animals is an argument from the analogy of 

 their actions with our own. " N'ow it is, of course, per- 

 fectly true that the less the resemblance the less is the 

 value of any analogy built upon the resembki ce, and 

 therefore that the inference of an ant or a bee feeling 

 sympathy or rage is not so valid as the similar inference 

 in the case of a dog or a monkey. Still it is an inference, 

 and, so far as it goes, a valid one — being, in fact, the 

 only inference available. That is to say, if we observe 

 an ant or a bee apparently exhibiting sympathy or rage, 

 we must either conclude that some psychological state 

 resembling that of sympathy or rage is present, or else 

 refuse to think about the subject at all ; from the observ- 

 able facts there is no other inference open " (p. 9). 



Assuming that we are justified in concluding that the 

 mental processes are similar when there are similar ex- 

 ternal appearances, ive still need a criterion of mental as 

 distinguished from reflex action ; for we find both in men 

 and animals examples of actions that are "mind-like and 

 yet not truly mental." " Objectively considered, the onlv 

 distinction between adaptive movements due to reflex 

 action and adaptive movements due to mental perception, 

 consists in the former depending on inherited mechanisms 

 within the nervous system being so constructed as to 

 effect particular adaptive movements in response to par- 

 ticular stimulations, while the latter are independent of 

 any such inherited adjustment of special mechanisms to 

 the exigencies of special circumstances" (p. 3). The 

 criterion proposed is therefore — " Does the organism 

 learn to make new adjustments, or to modify old ones, in 

 accordance with the results of its own individual experi- 

 ence?" If it does, we have evidence that the limit of 

 non-mental action has been passed ; that is, we are able 

 to fix, by means of this criterion, " the upper limit of non- 

 mental action." After distinguishing reflex from mental 

 action, it remains to distinguish " instinct " from "reason." 

 Dr. Romanes proposes to define instinct as "reflex action 

 into which there is imported the element of conscious- 

 ness," and "reason or intelligence" as "the faculty 

 which is concerned in the intentional adaptation of means 

 to ends " (p. 17). 



Dr. Romanes in his Introduction defends these last 

 definitions against several objections, but the strongest 

 argument that can be brought against them is found in 

 the actual treatment of the phenomena of instinct and 

 " general intelligence " in the chapters that follow. In 



