After many years of experimental investigation, I have long since fully demonstrated that the human constitution is developed in accordance with the universal plan of animal life, and the human brain is organized functionally in accordance with those higher laws of life, which control all the relations of the spiritual and material worlds,--all interaction between mind and matter. These primal laws are easily comprehended, and their application to the brain removes all the perplexing complexity of organology. Their application to the brain may be stated as follows: The upper legions of the brain, pointing upwards, relate to that which is above,--to the spiritual realm, to love, religion, duty, hope, firmness, and all that lifts us to a higher life. The lower regions point downwards, and expend their energy upon the body, rousing the heart and all the muscles and viscera, developing the excitements, passions, and appetites. The maximum upward tendency is at the middle of the superior region, and the maximum downward tendency at the middle of the basilar region, while organs half-way between them are neutral between these opposite tendencies. Hence every faculty or impulse has a location in the brain, higher or lower, as it has a more spiritual or material tendency, and as its influence on the character inclines to virtue or vice. The better the faculty, the higher its location,--the more capable of evil results, the lower it is placed. The higher position given to the nobler faculties accords with their right to rule the inferior nature, the predominance of which is evidently abnormal, and the effects of which, in this abnormal predominance, are expressed by terms full of evil, although their functions in due subordination are useful and absolutely necessary.