INTRODUCTION. ' 25 



we see. One finds that this habit of the human 

 mind is curiously automatic : for constantly when 

 we are in a "brown study," and even when we 

 are asleep, we find that attempts are being made, 

 although often of a vague and fatuous kind, to 

 give reasons for what chances to be occupying 

 the attention. The fact that this habit is uni- 

 versal among mankind, and that it is also innate 

 and automatic, asserts its extreme antiquity. 

 Probably in it we find the actual merging point 

 of instinct and reason. Like many other mental 

 and moral attributes which have come down to 

 us from the remote past, it is liable to get us 

 into grave trouble if not controlled by the most 

 vigilant discipline. Regarded in the light of a 

 very raw recruit, with Logic — that stern martinet 

 of the Intelligence Department — ever at its 

 elbow, it is still capable of rendering useful 

 service. 



The danger which besets us in accepting any 

 plausible explanation of phenomena without sub- 

 jecting it to the most searching criticism is not 

 death or wounds, as in the case of a primitive 

 hunter who formed a hasty and erroneous judg- 

 ment, but it is one which will certainly cripple 

 us as naturalists. 



