Januakt 7, 1910] 



SCIENCE 



17 



fant are functional phases of the simple 

 inborn neuro -muscular mechanisms of 

 these organisms. 



We do not know whether any glimmer of 

 consciousness is involved in these simple 

 processes; but if we study the behavior of 

 the whole series of animals from Amceha 

 to man objectively, we can find no point 

 where to an outside observer the behavior 

 which we called discriminative reaction in 

 a protozoan passes over into conscious 

 choice as we see it in our fellow men. The 

 series of stages is complete and iinbroken 

 until I begin to study my oivn choices, 

 when I find by introspection that the 

 whole mental fabric is involved — ratio- 

 cination, swayed perhaps now this way, 

 now that, by waves of feeling, and finally 

 will. Out of the psychic chaos of hesita- 

 tion and doubt I say, and I say truly, "I 

 have made up my mind," and action re- 

 sults. 



Now this seems to me a very different 

 thing from the discriminative reaction of 

 an amoeba, or even the deliberately judi- 

 cious act of a fellow man. Both of the 

 latter are alike in that I do not directly 

 experience feeling, will, etc., in connection 

 with them. Possibly if I could be succes- 

 sively for a time an amceba, a sea ane- 

 mone, a frog, a man and all the types of 

 animals between by the act of some benev- 

 olent Buddha, and if I could carry my 

 memory of each stage through all of the 

 others, then perhaps the psychic series 

 would appear at the end a simple and 

 unbroken graded series, as the objective 

 physiological series does to me now. 



Meanwhile, without intending at this 

 time to penetrate far into a field of philo- 

 sophical speculation which clearly lies 

 beyond the present limits of biological 

 science, I wish to make one further obser- 

 vation on the great problem of the relation 

 of mi^d and body. We have seen that 



animal bodies can be arranged in a graded 

 series (not a simple linear series, to be sure, 

 but a true series, nevertheless) of genet- 

 ically related forms; that animal activities 

 can be arranged in a similar graded series 

 of functions ; and that these two series are 

 closely related. In fact, they are abso- 

 lutely inseparable except by logical ab- 

 straction or some artificial scientific pro- 

 cedure, for their respective members are 

 related to each other as structure and 

 function, as objects and their properties,, 

 and neither can exist apart from the other. 



There is, however, a third series, the 

 psychic series, of which I know directl'jf 

 only one member — my own experience. 

 But I have satisfactory indirect evidence- 

 that the psychic series also extends for at 

 least a part of the distance parallel with 

 the other two. And wherever I can- 

 analyze this evidence it teaches that' 

 psychic processes, like physiological proc- 

 esses, are related to living bodies as func- 

 tions of their structures. If it be permis- 

 sible to generalize from these facts, and' 

 say that both physiological and psycholog- 

 ical processes may be included in the one- 

 category of function, we may conclude- 

 that we have not to reckon in science with 

 three independent genetic series, anatom- 

 ical, physiological and psychological, but 

 with one— a single series of functioning 

 structures, whose genetic continuity is 

 unbroken from its simplest to its most 

 complex members and which can be disso- 

 ciated, as is commonly done, only by doing 

 violence to truth. 



The present isolated position of the three- 

 disciplines of anatomy, physiology and' 

 psychology is due partly to the exigencies, 

 of practical pedagogical and methodolog- 

 ical convenience and partly to our incom- 

 plete knowledge of the facts. 



It is perhaps well to add that the posi- 

 tion here defined is as far removed as; 



