18 BIOLOGY AND ITS MAKERS 



while metaphysical speculation became the dominant form 

 of mental activity. 



Authority Declared the Source of Knowledge. — In this 

 atmosphere controversies over trivial points were engendered, 

 and the ancient writings were quoted as sustaining one side 

 or the other. All this led to the referring of questions as to 

 their truth or error to authority as the source of knowledge, 

 and resulted in a complete eclipse of reason. Amusing illus- 

 trations of the situation are abundant; as when, in the 

 Middle Ages, the question of the number of teeth in the horse 

 was debated with great heat in many contentious writings. 

 Apparently none of the contestants thought of the simple 

 expedient of counting them, but tried only to sustain their 

 position by reference to authority. Again, one who noticed 

 spots on the sun became convinced of the error of his eyes 

 because Aristotle had somewhere written "The face of the 

 sun is immaculate." 



This was a barren period not only for science, but also 

 for ecclesiastical advance. Notwithstanding the fact that 

 for more than a thousand years the only new works were 

 written by professional theologians, there was no substantial 

 advance in their field, and we cannot escape the reflection 

 that the reciprocal action of free inquiry is essential to the 

 growth of theology as of other departments of learning. 



In the period from the downfall of Rome to the revival 

 of learning, one eminent theologian, St. Augustine, stands 

 in relief for the openness of his mind to new truth and for 

 his expressions upon the relation of revelation in the Scrip- 

 tures to the observation of nature. His position will be more 

 clearly indicated in the chapter dealing with the rise of 

 evolutionary thought. 



Perhaps it has been the disposition of historians to paint 

 the Middle Ages in too dark colors in order to provide a 

 background on which fitly to portray the subsequent awak- 



