286 POPULAR SCIENCE MONTHLY. 



which he belongs. If now we study this man in respect to his mental 

 development, whether from the savage or the child, we find that the 

 direction of change has been away from imitative, impulsive action, 

 towards thought, reflection, deliberation. He continually makes more 

 use of memory and, anticipating the future, regulates his action in the 

 light of his past experience. This change from the imitative and 

 impulsive to the reasoning man accompanies the development of 

 the higher brain centers, particularly of the cerebral cortex, upon 

 which depend the all-important functions of memory and association. 

 As an experiment it is quite possible to reduce this highly developed 

 reasoning being in a single moment to a condition resembling his primi- 

 tive state by means of hypnotism. In hypnosis there is a temporary 

 paralysis or sleep of the higher brain centers, upon which depends 

 deliberative, rational action, and, the lower (older) centers alone being 

 active, the subject becomes a mere ideo-motor machine acting out 

 every suggestion. In various related states of automatism, where there 

 is any spontaneity at all, the mentality and morality of the subject are 

 of a lower type and may be called reversionary in character, owing, no 

 doubt, to the fact that those brain centers which represent the most 

 recent acquirements of the race are temporarily out of the circuit. 



If again we study the mind of the child, we find that it presents 

 many points of likeness to the mind of the hypnotic subject and to the 

 mind of the primitive man. We learn from biology that the child 

 is to some extent a recapitulation of the life of the race, passing 

 through in his individual development the stages of race development. 

 Physiologically speaking, the higher brain centers and the centers for 

 association, which are late acquirements of the race, are last developed 

 in the child. We are therefore not surprised to find that the child, 

 like the savage and the hypnotic subject, is imitative, impulsive, non- 

 reflective, incapable of much abstract thought, deliberation or reason- 

 ing, and that he acts with a view to immediate rather than remote ends. 



If now we turn to the behavior of the normal adult man in mental 

 epidemics and crazes of all kinds, from the Crusades to the Massacre 

 of St. Bartholomew, from the tulip mania in Holland to the Dewey 

 welcome in New York City, we observe that his behavior is to some 

 extent similar to that of the hypnotic subject, and the child, and the 

 primitive man. The general character of mental action in epidemics is 

 as follows: Men become imitative beings and their actions are deter- 

 mined by suggestion from the actions of others. Memory and the 

 association of ideas are inactive, and there is an inability to reason and 

 an indisposition towards deliberation and calm reflection. Past experi- 

 ences are disregarded, remote consequences are not seen and behavior 

 is impulsive and spasmodic. Feeling is very strong and every kind of 

 emotion is apt to be exaggerated. Calm observation is also lacking and 



