94 The Influence of Language and Environment upon the 



One of our most thoughtful writers has said that the best 

 study of mankind is man, and by this he doubtless means, as 

 we mean, that to study human nature is not merely to seek a 

 full acquaintance with the various portions of man's frame and 

 the duties assigned to each of his physical powers, but also the 

 influence of the bodily on the mental faculties, and, by conse- 

 quence, on the development of the individual character of each 

 subject. For the phenomena of human life must be divided into 

 two distinct classes or categories, (i) Those which appertain to 

 man in his animal nature, and (2) those which tend to lift him 

 above the level of the animal kingdom. To the superficial 

 student the second division is very difficult of comprehension, 

 and a popular but ignorant definition of metaphysics often 

 provokes a smile. It is that the science of metaphysics is 

 somebody trying to explain to another what he does not under- 

 stand himself. 



How external influences act and react upon the mental powers, 

 producing certain characteristics in one individual and others 

 in another, is imperfectly understood, but an investigation of 

 some of these phenomena will certainly be interesting, and 

 possibly instructive. Now, the influence of the organic powers, 

 indicated by such names as temperament, general predispo- 

 sition innate or acquired, functional troubles of nutrition, of 

 wants and inclinations, are represented by the ganglionic 

 nervous centres, while the influences of the physical world 

 through the senses are represented by the sensorial nervous 

 centres. But the influences of the subjective, or, as we may 

 term it, the spiritual world, are represented by psychocerebral 

 centres in which the ideas are severally imprinted with a 

 distinct modification. These three harmonize and combine 

 to produce all the phenomena of moral and intellectual life, and 

 this conclusion sums up the anatomical and physiological 

 formula of the phenomena of innervation and impressionability. 

 These considerations show the great interest which naturally 

 attaches to the influence of externals upon mind and character, 

 and to the intimate relationship between the nervous system and 



