792 



SCIENCE. 



[N. S. Vol. XX. No. 519. 



chological results. AA'hile, now, I take the 

 recent experimental work on memory and 

 the associations involved in memory to be 

 work of a high order; and while I believe, 

 in particular, that certain of the methods 

 employed are a valuable addition to our 

 psychological repertory, I can not but 

 think that the two tendencies just men- 

 tioned have not been kept as distinct as 

 they should have been, and that experi- 

 mental psychology has suffered in conse- 

 quence. We can hardly hope to get a psy- 

 chology of memory and association on the 

 ground of Reproduktionstendenz and Per- 

 severationstendenz : we can hardly hope to 

 get practical rules, if they are what we 

 want, out of the published studies on econ- 

 omy of learning. The Tendenz-concepts 

 are psychophysical, and tend to cover up 

 the complexity of actual experience; the 

 practical studies are made under condi- 

 tions widely remote from those that obtain 

 in ordinary practise. Let us realize that 

 we may attempt here any one of three dis- 

 tinct problems. We may aim at a psy- 

 chology of memory and association; i. e., 

 we may seek to record our experience, to 

 trace the introspective patterning of the 

 memory consciousness. We may aim at a 

 psychophysics of memory; i. e., we may 

 try to establish formula akin to the well- 

 known formula of Ebbinghaus' 'Gedacht- 

 nis, ' which represents retention as a func- 

 tion of time elapsed. Or we may aim at 

 an applied psychology of memory ; we may 

 work out, experimentally, an art of acqui- 

 sition. I do not say that an investigation 

 into one of these three topics will throw no 

 light on the other two ; on the contrary, I 

 have already insisted on the value of in- 

 direct results in psychological enquiries. 

 But in our thought, at any rate, the three 

 problems should remain separate and dis- 

 tinct. They offer, without doubt, a wide 

 field for future research. I would siiggest, 

 though with all reserve, that the psycholog- 



ical study of memory and association may, 

 in the long run, help us to clear up the 

 much-disputed question of the subcon- 

 scious. There are, as you know, experi- 

 mental psychologists who work simply in 

 terms of introspection and of physiological 

 process; there are others who interpolate 

 between these terms an unconscious or sub- 

 conscious mentality. I can not go into de- 

 tail ; but it seems to me that, if these dif- 

 ferences of opinion can in any connection 

 be brought into the laboratory for adjust- 

 ment, it is here, in the investigation of 

 memory and association, that we may hope 

 to introduce them. ' 



I come next (6) to action. You will re- 

 member that, in its early years, experi- 

 mental psychology was much concerned 

 with the psychophysics of action; indeed, 

 the problem of the 'personal equation' is 

 a good deal older than our laboratories. 

 This interest has never flagged. If we 

 have not heard so much of late about reac- 

 tion experiments, we have heard a great 

 deal about the psychophysiology and psy- 

 chophysics of voluntary movement. And 

 I think that we can leave those things to 

 take care of themselves ; we may, without 

 any question, look to the next few years 

 for improvements of technique, for revi- 

 sion of numerical determinations, for re- 

 casting of theories. That work is under 

 Avay. What I should like now to empha- 

 size is the need for investigation of the 

 more strictly psychological kind. Our 

 knowledge of the action consciousness is 

 still very schematic, very rough, in part 

 very hypothetical. It has been recognized 

 for some years that the reaction experiment 

 may be turned to qualitative, i. e., to an- 

 alytical account; but so far more use has 

 been made of this idea in laboratory prac- 

 tise than in research. We must start all 

 over again, and take the action conscious- 

 ness seriously. I once made a sort of re- 

 action experiment of the setting-up and 



