CORRELATION OF GROWTH. iW 



though each idea and potentiality were located there 

 in its own minute definite limit of space, and at- 

 tached to a definite mechanism of matter, for, says 

 Professor Ladd : " Everything which psychology 

 teaches as to the character of the mental phenom- 

 ena, and everything which physiology teaches as to 

 the nature of cerebral functions, discourages the 

 puerile attempt to connect separate mental images 

 or ideas with isolated nerve-cells as their product." ^ 

 But, rather, we should think of development and 

 mental potentialities as dependent upon certain states 

 of living matter, which states are the results of the 

 entire past history of that living matter, and which 

 thus determine the method of response to external 

 stimuli, and the direction which shall be taken by 

 the new energy constantly entering from the outside. 

 However, I do not venture here to attempt an elu- 

 cidation of that point. 



What it concerns us to observe is, that a simple 

 piece of living matter, torn from an individual, may 

 grow into a single individual, or, the piece being 

 further divided, it may give rise to several individuals. 

 But all the individuals are alike. There was but one 

 plan of development in the piece, no matter whether 

 it was producing one individual or a dozen. In 

 other words, the piece of living matter could react 



1 Ladd, Elements of Physiological Psychology, p. 555. 



