94 BIOLOGICAL LECTURES. 



without miracle into geologic times, that in some kind of 

 a way all degrees of intelligence are directly related, then 

 what in its degree is true for a chicken is also true for 

 man, and mental endowment is no more miraculous for one 

 than the other ; and one must need to look for his so- 

 called faculties where he must look for those of the chicken 

 or the dog, namely, as the outcome of the original endowment 

 of what we call matter, rather than as a supernatural alliance 

 with matter which is the common notion. Already enough is 

 known as to the material dependence of the mind upon the 

 body to warrant even judicial acts to be based upon chemical 

 analysis of bodily products ; that emotions of different kinds 

 yield corresponding chemical substances. Some of these pro- 

 ducts are harmful in the extreme, some poisonous, while 

 others are healthful and promotive of life. Brain building is 

 the end towards which this new science is reaching. One of 

 its axioms is that the mind can only be educated through the 

 senses, and the more senses and the better they are developed 

 the more mental power. Thinking is the function of gray 

 cellular matter that covers the brain like the rind of an orange. 

 Unconscious thinking vastly exceeds in amount our conscious 

 thinking. When thinking and doing have been repeated often, 

 they cease to be conscious acts, — they become automatic, in- 

 stinctive, and seem to sink out of conscious personality ; but 

 they may be summoned. So that unconsciousness makes the 

 most part of our lives. The individual starts with a bundle of 

 instincts, that is, inherited experiences, all unconscious, but 

 yet the product of consciousness ; and consciousness that has 

 all come from and through nerve action. All this may be so, 

 and yet the question still could be asked, are mind and matter 

 separable } One might point, as others have frequently done, 

 to the evidence of the growth and decadence of the mind along 

 with the growth and decadence of the bodily functions, of the 

 impairment of mental activity and quality when the brain or 

 stomach or liver is impaired, and full recovery when these are 

 brought to normal conditions again ; also how the individual 

 . lives over in himself the history of the race, as a mere animal 

 at first, then a savage, and lastly as an intellectual and moral 



