Herrick, Physiological Problems. 363 



clarifying our ideas and opening the way for further discoveries 

 as the purely a priori theories of Weismann. Although disclaim- 

 ing any approach to such equipment as might justity him m 

 attempting such construction, the writer ventures to offer a few 

 suggestions, relative to the direction along which such effort might 

 be made, and thus to indicate incidentally the views which he has 

 held for nearly two decades as to the general mechanics of 

 organisms. 



In view of the revival of interest from a strictly scientific point 

 of view in animal behavior as evidenced in the new departure in the 

 Journal of Comparative Neurology and the establishment of the 

 Journal of Experimental Zoology, it is quite in order to insist on 

 the dynamic interpretation of structure. 



In order to condense as much as possible we have chosen an 

 aphoristic form of statement followed by an illustrative commen- 

 tary. 



1. Matter, considered by Dalton to be composed of discrete 

 particles (atoms) more or less loosely connected to form larger 

 composite units (molecules) which are mathematically constant 

 and definitely related to other units, and which has further been 

 analyzed by modern physics into ions (the protons of older specu- 

 lative writers), is a purely metaphysical concept. . For this we 

 substitute that of energy whose sole characteristic as such is that 

 of spontaneous activity (finding expression in our consciousness 

 as the simple element "change"). Energy is the metaphysica 

 postulate of being and is not otherwise definable to the science than 

 as the counterpart of the simple real in consciousness or experience 

 (change). 



2. When manifested to human perception energy assumes the 

 form of force which is the counterpart of change in terms of mo- 

 tion. As the concept of motion involves that of space and produces 

 it in experience, we may say roughly that force is energy manifested 

 in terms of space or under spacial limitations. 



3. Experience recognizes units or individuals making up objects, 

 which units may be unlike among themselves or sensibly sim- 

 ilar. Numerous similar elements may be embraced in a greater 

 composite individual. Dynamically these units are expressed as 

 specific forms or modes of motion. Since force always involves 

 a tendency to change, we may say that each such unit may be 

 represented by a locus formula for a single cycle of its motion. 



