Preface. 



ment and a mind forming instrument. Our ancestors were in the 

 habit of looking entirely too high for the explanation of the phenomena 

 of sensation and mind. They never dreamed that these were physical 

 phenomena, or connected in any way with the motions of material bodies 

 with which they were familar. The true course of knowledge is not from 

 above downward, but from below upward, and but little progress is possible 

 where this principle is ignored. The advancement of the present gen- 

 eration has been greatly assisted by its partial emancipation from the 

 dominance of the past with its essentially vicious metaphysical methods. 

 The study of dynamic agencies and the inferences justified by the in- 

 ductive method of considering them, furnish us with all the real know- 

 ledge of causes and effects that we possess. We easily connect these 

 agencies with the motions that constitute vitality and mentality and 

 discover that the energies of the environment constitute the antecedents 

 of specialized function. As these energies build up bodies of dif- 

 ferent shapes, the forms of the reactions from them correspondingly 

 change. We have motion before we have locomotion and we have 

 locomotion before legs; we have circulation before hearts, nerve currents 

 before nerves, and mental action before brains. Thus function oper- 

 ates in the modification of organs and by cumulation of modifications 

 in their re-creation. 



The Dynamic Theory, by showing the connection between the ex- 

 ternal stimulation and its internal sequel in mental action, proves both 

 of them to belong to the same class of physical motion. A study of 

 mental action therefore demands and includes an investigation of the re- 

 lated and antecedent physical phenomena. When these are all considered 

 together we soon perceive that they belong together. Particularly are 

 the* phenomena of mentality and vitality seen to be inseparable. In 

 fact all organic reactions partake of both vital and mental characteris- 

 tics, and when we consider the more elementary organisms, the two 

 'merge into each other till it becomes impossible to make any distinction 

 between them. A similar consideration extended to other branch^ of 

 physical phenomena show them to be all derived from a common 

 stock, and that finally we must consider all energy as only one. 



Finding ourselves involved in the effects of these various dynamic 

 agencies, the study of them and the ways in which they affect us, be- 

 comes a matter of personal interest to everyone; and it is not too much 

 to say that it is a duty everyone owes to himself to pursue such study 

 as far as practicable. It is a sort of duty that, like eating, breath- 

 ing or exercising, cannot be delegated or performed by proxy; and its 

 neglect involves x an abdication not only of power, but of liberty. 



The facts I have presented have been drawn from the most reliable 

 scientific authorities. The following list includes those most quoted: 



