No. 606] BIOLOGICAL EXIGMAS 323 



progress represented by the modern electro-molecular 

 conception of the physical universe has been achieved by 

 the utilization of a few general conceptions, such as those 

 of the electron and electrical action at a distance, These 

 conceptions, although general, i. e., universally applicable, 

 are nevertheless extremely definite. They are also as 

 tangible, or concrete, as it is possible to make them. It is 

 nearly as characteristic of the modern theory of matter 

 to eliminate abstractions as it is for it to gather up scat- 

 tered facts and theories to unite them into an integral 

 system. Although elements of abstraction still remain, 

 they are reduced to a minimum by the increasing tend- 

 ency to demand not only an algebraic symbol, but a visual 

 picture of the processes of nature. 



II 



It is perhaps not surprising that the astonishing prog- 

 ress of general physics during recent times should thus 

 far have failed to exert any very notable influence upon 

 the science of biology. From the point of view of the 

 physicist, biological problems must be regarded as ques- 

 tions of special material structure, usually of a very in- 

 tricate character, and involving the arrangement and his- 

 tory of units of matter for the most part larger than those 

 upon which his attention is immediately concentrated. 

 The program of modern physics is to build up the theory 

 of all material structures by means of geometry and the 

 d^Tiamics of electrical particles. The first problem, 

 logically, is that of the constitution of the atom, and as 

 the solution of this problem is still unfinished, too much 

 should not be expected of our knowledge of the config- 

 uration of particles and forces in higher aggregates of 

 matter. 



However, a critic who sees current events in the light 

 of the history of science can hardly escape a twinge of 

 disappointment at the recrudescence in biological theory, 

 at the present time, of the doctrine of vitalism. The pres- 

 ent, of all periods in the history of thought, is an hour of 

 triumph of the monistic theory of nature, and yet now, 



