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SCIENCE 



[N. S. Vol. XLI. No. 1054 



of method too seriously. Other sciences 

 have the same trouble with definitions. It 

 would be as difficult to find a single phrase 

 that would mark off physics from chemis- 

 try in an absolutely accurate and adequate 

 way as to distinguish psychology from 

 anthropology or human physiology, and 

 quite as difficult to formulate a definition 

 of either chemistry or physics that would 

 satisfy every one, as to define psychology. 

 From most traditional definitions, J. J. 

 Thomson as physicist has no right to be 

 discussing atoms, and similar violations of 

 the sacred rights of physics as defined in 

 the text-books might be cited on the part 

 of men who are generally labeled as chem- 

 ists. These men, and the better men in the 

 sciences in general, are not interested in 

 phrasing definitions but in solving the 

 problems that their science, or closely re- 

 lated sciences present to them. On our 

 side, much of the discussion, or the liveli- 

 ness of the discussion, comes from the fact 

 that we assume that the definition must 

 determine the science rather than the sci- 

 ence the definition. It is assumed, tacitly, 

 to be sure, that a definition is logically 

 prior to the science, is a statement from 

 which the science may be deduced or a 

 program that the science is to follow in its 

 development rather than a mere statement 

 of what the science has done, or a formula- 

 tion, as best we may, of the aims common 

 to the mass of workers who are generally 

 accepted as psychologists. 



If we are to accept the view that a defi- 

 nition is the servant of our science rather 

 than its master, if we are to say with Judd 

 "that we all know what psychology is," 

 then the test of a definition is that it shall 

 state the aims of the science in the briefest 

 form possible, and in terms that shall be 

 best understood by the individuals for 

 whom it is intended, that shall be least 

 open to misunderstanding. If we consider 



the traditional definitions we find that each 

 is open to certain objections when tested 

 by these criteria. The traditional science 

 of mind implies a general agreement as to 

 what mind is, and this is lacking. It also 

 suffers from the implication to men who 

 do not know what psychology is that we are 

 to deal with an entity of some sort, for all 

 terms after they become familiar come to 

 be regarded as denoting things. "When 

 mind is defined in a way to avoid this im- 

 plication, as it usually is in the succeeding 

 sentence, it is no longer recognizable by the 

 uninstructed. The same objections hold 

 against consciousness; it was at first inno- 

 cent enough of mystical significance, but 

 a very few years of use to designate the 

 material to be studied set it up as a thing 

 or inner force. Hypostatization followed 

 close upon the heels of its entrance into 

 definitions. If psychologists were to study 

 it as the material of their science it must 

 be the equivalent of mind as mind is of 

 soul, it must then be an active agent that 

 psychologists can see, although, like the holy 

 grail, sight of it is granted only to the pure 

 in heart. Experience as a substitute for 

 consciousness or mind escapes some of the 

 disadvantages in that it is less likely to be 

 personified or substantialized, but it is diffi- 

 cult accurately to separate the part of 

 experience that psychology is to treat from 

 that touched upon by the other sciences. 

 When this is accomplished it affords little 

 advantage over mind or consciousness. 



In view of all these circumstances a 

 change from the inside to the outside, to 

 describe the object of psychology as behav- 

 ior, offers the most advantages. Behavior 

 is at once simple enough to require the 

 minimum of definition and is hardly capa- 

 ble of being transformed in meaning to 

 designate a thing or force. It takes, too, 

 the attitude toward the mental of the aver- 

 age non-reflective individual. The ordinary 



