88 DEVELOPMENT AND PURPOSE CHAP. 



entering in as a content, determined correlation without 

 being itself a term in correlation. This series of changes 

 would seem to be completed in idea by the inclusion of the 

 conditions on which its own existence depends. We are 

 now, therefore, in a position to take a summary view of the 

 succession of phases in the evolution of Mind. 



We have been led then to conceive of life as the process 

 of a psycho-physical structure which grows up in inter- 

 action with the environment and which acquires, through 

 the medium of correlations of which consciousness is the 

 essential organ, the power of directing its own fortunes. 

 In the lowest stages consciousness is undeveloped, and the 

 response to the environment, at first wholly random and 

 useless, is gradually directed in paths which are normally 

 suitable to vital needs by the action of heredity. This is 

 the stage of the ' Structural' action and the hereditary 

 reflex, which controls the immediate response to direct 

 sense-stimuli. So far correlation is based on the heredi- 

 tary structure. To meet the individual variation of such 

 stimuli a special correlation of co-present sense-data is 

 required, and this is the first work of consciousness in 

 sensori-motor action. The feeling-tone determining this 

 correlation from moment to moment may be so adjusted, 

 through the influence of heredity, as to guide trains of 

 action towards ends of vital service. Such a train of action 

 is called an Instinct. Correlation based on heredity is here 

 combined with correlation based on present conditions. 

 From this we pass to correlation based on Individual and 

 Social experience. This yields first the formation of habit 

 and trained skill resting on the correlation of sense-stimulus 

 with feeling under the influence of related consequences. 

 There is a massive, indirect or inarticulate correlation of 

 individual experiences. In the next stages these conse- 

 quences come into consciousness, distinct elements are 

 grasped in their relations and anticipatory ideas are formed 

 on the basis of perception under the influence of under- 

 lying affinities. Particular experiences are articulately or 

 directly correlated. Next, these affinities come into con- 

 sciousness and we have a Correlation of Universals, in 

 which experience is organised into bodies of thought and 



