CHAPTER VII. 

 PSYCHIC GRADATIONS. 



Psychological unity of organic nature. Material basis of the soul : 

 psychoplasm. Scale of sensation. Scale of movement. Scale 

 of reflex action. Simple and compound reflex action. Reflex 

 action and consciousness. Scale of perception. Unconscious 

 and conscious perception. Scale of memory. Unconscious and 

 conscious memory. Association of perceptions. Instinct. 

 Primary and secondary instincts. Scale of reason. Language. 

 Emotion and passion. The will. Freedom of the will. 



The great progress which psychology has made, with 

 the assistance of evolution, in the latter half of the 

 century culminates in the recognition of the psycho- 

 logical unity of the organic world. Comparative 

 psychology, in co-operation with the ontogeny and 

 phylogeny of the psyche, has enforced the conviction 

 that organic life in all its stages, from the simplest 

 unicellular protozoon up to man, springs from the 

 same elementary forces of nature, from the physio- 

 logical functions of sensation and movement. The 

 future task of scientific psychology, therefore, is not, 

 as it once was, the exclusively subjective and intro- 

 spective analysis of the highly-developed mind of a 

 philosopher, but the objective, comparative study of 

 the long gradation by which man has slowly arisen 

 through a vast series of lower animal conditions. 

 This great task of separating the different steps in 

 the psychological ladder, and proving their unbroken 



no 



