March 18, 1887.] 



SCIENCE. 



257 



because consciousness, and consequently will, are 

 involved ; it is instinctive, because it is an instinct 

 necessary to the preservation of life, and common 

 to all beings, to avoid a contact which gives rise 

 to pain ; finally, it is reflex, for it is not deter- 

 mined by the will, and the withdrawal of the 

 hand is effected before the resolve to withdraw it 

 is made. Here, then, is an elementary reflex act 

 which is at the same time intelligent and instinc- 

 tive. Among the lower animals many instinctive 

 movements are nothing but reflex actions. A 

 limpet clings to its rock : it is but slightly fas- 

 tened, and moves but slowly over the surface of 

 the stone. But touch its shell, and attempt to lift 

 it, and instantly it fastens itself firmly to the 

 rock ; and to detach it a very great expenditure of 

 effort is necessary. Its firm adhesion to the stone 

 has been instinctive, suddenly and resistlessly de- 

 termined by contact with the aggressor. It is a 

 reflex action, but instinct is also involved. 



It is truly impossible to say just where instinct 

 begins and reflex action ends. The two phenomena 

 intermingle, and instinct should be regarded as a 

 complicated reflex action. 



' Intelligence,' ' instinct,' ' reflex action,' — these 

 are the three terms of psychology. Between these 

 three forms of activity there is no barrier, no 

 hiatus, no abyss. The gradation is regular and 

 without leap. And why should it not be so ? 

 Where in nature can sudden transitions, the exist- 

 ence of which was denied even by Aristotle, be 

 found ? Sudden appearances of a new phenome- 

 non are not known. Between the man and the 

 animal there is hardly any distinction. There is 

 hardly any between the animal and thei)lant, and 

 the beginnings of psychology are in the begin- 

 nings of life itself. It would be a useless task to 

 attempt to limit psychology to the phenomena of 

 instinct or of intelligence. Psychology commences 

 with reflex action; so that its domain includes 

 elementary reflex action, the movement by which 

 the limpet clings closer to the rock, as well as the 

 most complicated intellectual operation, for in- 

 stance, the discussion of the Abelian functions. 

 In what follows we shall see how, by successive 

 steps, psychical action frees itself little by little 

 from the elementary reflex phenomenon. Our 

 aim has been to take the psychic phenomenon at 

 its origin, however humble that may be, and to 

 follow it in its progress through the uninterrupted 

 series of living beings. 



n. 



It is this synthetic treatment that seems to 

 us to merit the title of 'general psychology.' 



The term is rarely used ; but we believe that it 

 deserves to take its place among the sciences. We 



speak of general physiology, and the term is per- 

 fectly definite. The same should be true of general 

 psychology. Chemistry is the science that treats 

 of the molecular transformation of matter. Ac- 

 cording to the stand-point that is taken, we have 

 a chemistry without any particular designation, 

 treating of all the divisions of chemistry, or we 

 have mineral chemistry, organic chemistry, physi- 

 ological chemistry, industrial chemistry, analyti- 

 cal chemistry. But there is also a general chem- 

 istry, which passes over in silence both the par- 

 ticular facts, the details of which are without 

 number, as well as their applications and the 

 technique built upon them, while only the general 

 laws of chemistry are discussed. The special sub- 

 ject of general chemistry is the totality of the 

 molecular transformations of matter, — the theory 

 of atoms, their affinities and classifications, the 

 equivalence of forces, and so forth. Physiology, 

 or the science of life, can also be studied from 

 diverse points of view. We have physiology 

 without any particular designation, which com- 

 prehends all the subdivisions of the science ; hu- 

 man physiology, which studies specially the vital 

 phenomena of man and the higher animals ; com- 

 parative physiology, which treats of the vital 

 functions of all animals in comparing the life of 

 all beings from the lowest of animal forms to 

 man. which is the highest development ; vegetable 

 physiology, which treats of the vital functions of 

 plants ; pathological physiology, which has to do 

 with the functions of life as modified by disease ; 

 and, finally, general physiology, of which life in 

 general forms the subject-matter. Details are 

 passed over in silence, for tbey are due to special 

 conditions which are almost invariably peculiar to 

 some group of animals or other. 



Such is the raison d'etre of general physiology. 

 It is the synthesis of all physiology, but of physi- 

 ology apart from the myriad of details which en- 

 cumber it, and set forth only in its main outlines 

 and in its most general laws. While the classic 

 works of physiology develop the complexity, 

 which is almost infinite, of the vital function, 

 general physiology presents us the picture of the 

 grand unity of life as it is manifested, under 

 forms so extremely diverse, on the surface of the 

 earth. 



Psychology, like physiology, falls into several 

 very distinct divisions. There is a psychology 

 without designation, which treats of psychology 

 in its entirety and under all its phases ; also a 

 human psychology, limited to the study of the 

 intelligence of man ; also a comparative psychol- 

 ogy, by which are analyzed the phenomena of 

 intelligence exhibited by animals and allied to 

 those manifested by man himself ; a pathological 



