92 DEVELOPMENT AND PURPOSE CHAP. 



We are to conceive the great forces of the human mind 

 as still operating from the background in the dark. The 

 light of consciousness falls, as it were, on the .surface of a 

 deep sea of energy. It stirs forces that reach far down into 

 the depths, and these forces determine the movements and 

 rearrangements within the lighted area, but without them- 

 selves emerging into the light. Ideas are formed, names 

 are given, judgments are passed, inferences drawn, emotions 

 stirred, desires conceived and plans of action resolved 

 upon, and the whole play is played out on the illuminated 

 area. Perception gives the cue, deliberate action super- 

 venes, and further perceptible results follow, but to trace 

 the real causes to their roots we should have to go below 

 to forces which are not formulated and are perhaps but 

 obscurely felt. Nevertheless as the work of correlation 

 advances, certain governing modes of conception begin to 

 stand out. Without being recognised as explicit principles 

 of correlation, possibly without even being named and 

 known on their own account, there emerge certain structural 

 forms of great generality which come to govern the work 

 of correlation, give shape to the entire order, and direct 

 the work of construction. These structural forms are 

 what are known as the categories of common sense, such 

 categories as those of substance and attribute, cause and 

 effect, space and time, action and passivity, persistence and 

 change, .sameness and difference. Themselves educed from 

 experience they react powerfully and that long before 

 they are named and known for what they are on the em- 

 pirical order. To understand this action it is not necessary 

 to suppose, after the fashion of the Transcendental Analytic, 

 that nothing could be experienced that does not conform 

 to certain pre-existing categories. It is sufficient that 

 whatever when experienced is seen to fall within the limits 

 of one or other of them acquires thereby a certain local 

 habitation within the existing order. What will not 

 square with them is vague, meaningless and obscure. It 

 hovers doubtful on the confines of consciousness. It can- 

 not get itself expressed, nor enter into the ever-living 

 medium of language, which alone confers permanence on 

 the fleeting experiences of man, and so it flutters away 



