So POPULAR SCIENCE MONTHLY 



the Young-Helmholtz theory of color, presents investigations about 

 which psychologists are bound to trouble for many a day. 



Thus, the significance of Helmholtz's career may be traced to his 

 combination of the mathematical and exact-scientific with the human- 

 istic interest, a union to which we may attribute our greatest advances 

 alike in science and in intellectual insight. And this fitted him rarely 

 to execute work of abiding value for physiological psychology. No one 

 has contrived to reach better results in those unplumbed reaches of 

 experience where the joint action of body and mind can be studied 

 with a measure of success. Proceeding from the theory of " specific 

 energy " of his master Miiller, he wrought it out in detail, eminently 

 for the mechanism of sight and hearing, by experimental methods and 

 by mathematico-physical analyses. Upon the romantic interest in 

 nature stimulated by Schelling he superimposed the critical processes 

 of Kant, armed with all the resources of the most delicate apparatus 

 and rigid analytic procedure. This coalition of endowment and out- 

 look continued in the three leaders who were destined to build psy- 

 chology into an independent science — Lotze, Fechner and Wundt. To 

 them we shall turn next. 



