440 PKACTICAL APPLRATIOXS OF MODEUX PSYCHOLOGY. 



There is, however, a new school of psychologists who regard their 

 subject as the " science of behaviour ": they deal chiefly with 

 considerations of the emotions and sensations of the liunian 

 being. It is probable that this school arose through the increased 

 interest in sociology and the enforced study of war-neuroses and of 

 abnormal behaviour in the individual and the herd. These 

 Behaviourists, as we call them, would seem to pay more heed to 

 the physiological changes in the individual than to the specific 

 mental and psychic causes and effects of such changes. 

 Undoubtedly there must be many changes of the organism which 

 are unobserved, and the interesting question arises as to how far, 

 if at all, such unobserved changes can affect other people, and so 

 be called " behaviour." This point is still very much in dispute, 

 but we cannot deal with that controversy here. The Behavioui'ist 

 School, in their very much simplified and therefore inadequate 

 system, do away entirely with what is generally known as the 

 Sub-conscious ; but this is a factor of great importance in the work 

 of the other schools — as will be seen later. A middle school 

 between the two mentioned above regards psychology simply as 

 the study of human mental reactions in the individual, and its 

 task as the collation and comparison of its observations in this 

 direction. The method of study chiefly employed by the old 

 school was that of introspection — looking within themselves to 

 gauge and classify their experiences and sensations, and to deter- 

 mine by this same means the stages and processes of rationalisa- 

 tion and thought. Although this method did, indeed, teach them 

 a considerable amount, yet for obvious reasons it was untrust- 

 worthy. Not always was the older psychologist able to remember 

 that when he was introspecting he was looking within a psycho- 

 logist; and no one was likely to adopt the science who had not a 

 certain distinctive type of mind and taste — a factor which it was 

 not always easy to eliminate when casting general principles and 

 empiricisms. Perhaps the most important and most promising 

 method of research conducted at the present day is that which is 

 known as " experimental psychology." By this must be under- 

 stood not a modern school who differ from the stable middle school 

 mentioned above, but simply the method of those who have 

 adopted laboratory work as a complementary means of study. 

 This laboratory work may roughly be classed under two headings : 

 (a) physical — the study of sensations, etc. ; (b) mental — the study 

 of the degree of acuity of apprehension, memory-span, etc. Of 

 the actual technique of the experimental work and of the variety 

 of special apparatus employed, though of great interest, we 

 cannot wi'ite at present. 



It is claimed that by means of this work the degree of 

 mentality, sensibility to stimuli, and manual dexterity can be 

 measured and classified; and if this claim be justified it follows 

 that practical applications of these methods should be useful in 

 every occupation where such factors are of importance. That this 

 claim is justified we shall briefly endeavour to show. 



Tt is obvious that in the course of a very limited paper, and 

 especially when dealing with a subject of universal application, 



