October 7, 1922] 



NA TURE 



489 



persisted in a condition of unconscious existence, and 

 he emphasised the biological importance of suppression. 

 He considered at first that the protopathic sensibility 

 " has all the characters we associate with instinct," 

 whereas the later epicritic sensibility has the characters 

 of intelligence or reason. So he came to hold that 

 instinct " led the animal kingdom a certain distance 

 in the line of progress," whereupon " a new develop- 

 ment began on different lines." " starting a new path, 

 developing a new mechanism which utilised such por- 

 tions of the old as suited its purpose." 



Evoluiio per saltus was thus the keynote of Rivers's 

 views on mental development. Just as the experience 

 of the caterpillar or tadpole is for the most part sup- 

 pressed in the experience of the butterfly or frog, so 

 instinctive reactions tend to be suppressed in intelli- 

 gent experience whenever the immediate and unmodifi- 

 able nature of one becomes incompatible with the 

 diametrically opposite characters of the other. Just 

 as parts of the protopathic fuse with the later acquired 

 epicritic sensibility, so parts of our early experience, of 

 which other parts are suppressed, fuse with later ex- 

 perience in affecting adult character. " Experience," 

 he explained, " becomes unconscious because instinct 

 and intelligence run on different lines and are in many 

 respects incompatible with one another." 



From his point of view Rivers was naturally led, 

 wherever possible, to interpret abnormal mental con- 

 ditions in terms of regression to more primitive, hitherto 

 suppressed activities. He held that the hysterias are 

 essentially " substitution neuroses," connected with 

 and modified by the gregarious instincts, and are 

 primarily due to a regression to the primitive instinct- 

 ive danger reaction of immobility, greatly modified by 

 suggestion. So, too, he held that the anxiety neuroses, 

 which are for him essentially "repression neuroses," 

 also show regression, though less complete, in the 

 strength and frequency of emotional reaction, in the 

 failure during states of phantasy to appreciate reality, 

 in the reversion to the nightmares, and especially the 

 terrifying animal dreams, characteristic of childhood, 

 in the occurrence of compulsory acts, in the desire for 

 solitude, etc. He criticised Freud's conception of the 

 censorship, substituting in place of that anthropo- 

 morphically-coloured sociological parallel the physio- 

 logical and non-teleological conception of regression. 



We are now in a position to examine Rivers's treat- 

 ment of the gregarious behaviour of animal and human 

 life, on which he was still engaged at the time of his 

 death. In the gregarious instinct he recognised a 

 cognitive aspect which he termed " intuition," an 

 affective aspect which he termed " sympathy," and a 

 motor aspect which he termed " mimesis." He used 

 " mimesis " for the process of imitation so far as it was 

 unwitting ; " sympathy " he regarded as always un- 

 witting. " Intuition " he defined as the process 

 whereby one person is unwittingly influenced by 

 another's cognitive activity. But I feel sure that the 

 term " unwittingly " is not to be considered here as 

 equivalent to " telepathically." All that Rivers meant 

 was that the person is influenced by certain stimuli 

 without appreciating their nature and meaning. He 

 preferred to employ the term " suggestion " as covering 

 all the processes by which one mind acts on or is acted 

 on by another unwittingly. He supposed that in the 



NO. 2762, VOL. I 10] 



course of mental evolution epicritic characters dis- 

 placed the early protopathic characters of instinctive 

 behaviour owing to the incidence of gregarious life, 

 especially among insects, and owingf to the appearance 

 and development of intelligence, especially in man. 

 The suggestion inherent in gregarious behaviour im- 

 plies some graduation of mental and bodily activity — 

 an instinctive and unwitting discrimination distinct 

 frcm the witting discrimination of intelligence 



Were he here to-day Rivers would have carried this 

 conception of the evolution of gregarious life still 

 further by distinguishing between the more lowly 

 leaderless herd and the herd which has acquired a 

 definite leader. He would have traced the develop- 

 ment of the new affect of submission and of the new 

 behaviour of obedience to the leader, and he would 

 doubtless have accredited the leader with the higher 

 affects of superiority and felt prestige, with the higher 

 cognition that comes of intuitive foresight, and with 

 the higher behaviour of intuitive adaptation, initiative, 

 and command. I expect, too, that he would have 

 sketched the development of still later forms of social 

 activity, complicated by the interaction and combina- 

 tion of intellectual and instinctive processes — the 

 witting deliberations and decisions on the part of the 

 leader, and the intellectual understanding of the 

 reasons for their confidence in him and for their 

 appropriate behaviour on the part of those who 

 are led. 



But it would be idle further to speculate on the ideas 

 of which we have been robbed by Rivers's untimely 

 death. Let us rather console ourselves with the vast 

 amount of valuable and suggestive material which he 

 has left behind and with the stimulating memories of 

 one who, despite the fact that his health was never 

 robust, devoted himself unsparingly to scientific work 

 and to the claims of any deserving human beings or of 

 any deserving humane cause that were made upon him. 

 There are, no doubt, some who believe that Rivers's 

 earlier experimental psychological work — on vision, 

 on the effects of drugs, and on cutaneous sensibility — 

 is likely to be more lasting than his later speculations 

 on the nature of instinct, the unconscious, dreams, and 

 the psychoneuroses. No one can doubt the scientific 

 permanence of his investigations in the laboratory or 

 in the field ; they are a standing monument of 

 thoroughness and accuracy combined with criticism 

 and genius. But even those who hesitate to suppose 

 that at some definite period in mental evolution in- 

 telligence suddenly made its appearance and was 

 grafted on to instinct, or that epicritic sensibility was 

 suddenly added to a mental life which had before 

 enjoyed only protopathic sensibility — even those who 

 may not see eye to eye with Rivers on these and other 

 fundamental views on which much of his later work 

 rested, will be foremost in n 1 ogni ing the extraordinary 

 stimulating, suggestive, and fruitful character of all 

 that he poured forth with such astounding speed and 

 profusion during the closing years of his life. Above 

 all. we mourn a teacher who was not merely a man of 

 science devoted to abstract problems, but who realised 

 the value of and took a keen delight in applying the 

 km iwledge gained in his special subject to more real and 

 living problems of a more concrete, practical, everyday 

 character. Rivers's careful methods of investigating 



