ZOOLOGY AND INTELLECTUAL PROGRESS 347 



The Revival of Learning. — But the human mind, ever restive to 

 discover the relation between causes and effects in the production of 

 natural phenomena, would not permanently brook this restraint. The 

 minds of the more energetic and independent thinkers revolted against 

 the reign of authority, and, under the leadership of such minds, there 

 began a reform that is known to us all under the title of the revival of 

 learning, a reform of wide extent and of great importance to the hu- 

 man race. I wish to take a few minutes to point out that the essence 

 of this reform consisted in a change in the method of the pursuit of 

 knowledge. 



This so-called revival of learning affords a striking illustration of 

 how a change in mental interests may have great consequences for those 

 who engage in it. Let us first picture to ourselves the fruits of the 

 mental life of the middle ages, and then contrast this with the results 

 of the changed method of ascertaining truth introduced at the time of 

 the revival of learning. 



It is an old, oft-repeated story, how with the overthrow of ancient 

 civilization the torch of learning was nearly extinguished. Not only 

 was there a complete political revolution; there was also a complete 

 change in the mental interests of mankind. The situation was com- 

 plex, and it is true that there were many influences at work, but the 

 extinction of all scientific activity which occurred at this time was due 

 to a complete arrest of inquiry into the phenomena of nature. The 

 physicist no longer experimented, the naturalist no longer sought for 

 relation and causes in living beings. 



One circumstance that played a considerable part in the cessation 

 of scientific investigation at this time was the rise of the christian 

 church and the dominance of the priesthood in intellectual as well as in 

 spiritual life. The world-shunning spirit, so scrupulously cultivated 

 by the early christians, promoted a spirit that was hostile to observation. 

 The behest to shun the world was acted upon too literally. The eyes 

 were closed to nature and the mind was directed towards spiritual 

 matters, which truly seemed of higher importance. Presently the ob- 

 servation of nature came to be looked upon as proceeding from a prying 

 and impious curiosity — as an attempt to search out the concealments of 

 the Almighty. 



Books were scarce, schools of philosophy were reduced, and any gen- 

 eral dissemination of learning ceased. The priests who had access to 

 the books assumed the direction of intellectual life. But they were 

 largely employed with the analysis of the supernatural, and without the 

 wholesome checks of observation and experiment, mystical explanations 

 were invented for natural phenomena, while metaphysical speculation 

 became the dominant form of mental activity. 



Authority declared the Source of Knowledge. — In this atmosphere 

 free inquiry could not live, controversies over trivial points were en- 



