32 



be allowed to blind us to the evils arising from their 

 abuse. 



Having illustrated the dependence of mental activity 

 upon the character and quantity of food, upon the purity 

 and temperature of the air, and upon the amount and 

 degree of muscular exercise, the lecturer said that did we 

 realize how largely what we esteem our supremely intel- 

 lectual life receives influential promptings from functional 

 processes in obscure and despised organs of the body, we 

 should not only be amazed, but be inclined to esteem phys- 

 ical training quite as important as the inculcation of ideas. 



The lecturer then passed to speak of the physical basis 

 for the controlling power of thought. Thoughts consume 

 nervous force. Thoughts according to their intensity 

 may have an inhibitory action on each other. If this be 

 so it follows that the best conflict with one's evil propen- 

 sities is indirect that is, by immediate exercise of our 

 faculties with thoughts and deeds conscience approves, 

 rather than by attempts to increase the power of the will 

 to rule, by drilling it in direct contests with vicious in- 

 clinations. If to expel evil we call in virtuous thoughts 

 to occupy our mental energies, we intensify habits of 

 mental action which will automatically assert their exis- 

 tence, and evil propensities will waste and weaken and 

 perish from disuse. 



This course of lectures has been listened to with deep 

 interest, not for entertainment only, but principally to 

 ascertain from a scientific stand-point the "mysterious 

 connection between mind and matter" acknowledged and 

 recognized by all, but capable of full comprehension by 

 those only who are willing to patiently investigate the 

 subject. Dr. Johnson is entitled to gratitude for the 

 light he has thrown upon this important subject. 



