348 THE POPULAR SCIENCE MONTHLY 



gendered and the ancient writings were quoted as sustaining one side 

 or the other. All this led to referring questions as to their truth or 

 error to authority as the source of knowledge, and resulted in a com- 

 plete eclipse of the reason. 



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

 enough, for those studies which were especially engaged in. Notwith- 

 standing the fact that for more than a thousand years all the new works 

 were written by theologians, there was no substantial advance in their 

 field of learning, and the reflection comes to us that the reciprocal ac- 

 tion of free inquiry is an essential condition for the growth of any de- 

 partment of learning. 



We should remember that the mental life of the Middle Ages was 

 active. It is a mistake to suppose that men of those times differed 

 much in their mental powers from those, of to-day. The medieval phi- 

 losophers were masters of the metaphysical method of argument, and 

 their ingenuity and mental alertness were great. The principal thing 

 that held progress in check was the method of setting about to ascer- 

 tain truth. 



Renewal of Observation. — It was an epoch of great importance, 

 therefore, when men began again to observe, and to attempt, even in an 

 unskilful way, hampered by intellectual inheritance and habit, to unravel 

 the mysteries of nature and to trace the relation between causes and 

 effects in the universe. The new movement was, as previously said, a 

 revolt of the intellect against existing conditions. In this movement 

 were embraced all the benefits that have resulted from the development 

 of modern science. The invention of printing, the voyages of mariners, 

 the growth of universities, all helped in a general way, but just as the 

 pause in science a thousand years or more earlier had been owing to the 

 "turning away from nature and to new mental interests, so the revival 

 was a return to nature and to the method of science. 



The Widening Horizon. — The reign of authority in intellectual mat- 

 ters lasted for twelve centuries, and then gave way gradually to the 

 reign of observation and reason. Under the influence of the new 

 method we have been moving generation by generation into a state of 

 clearer discernment and into an intellectual atmosphere of wider 

 horizon. 



There is an inspiration in this ever-widening horizon. We must 

 recognize, I think, that there has been a reconstructive force accom- 

 panying scientific progress. Wherever traditional opinion has been 

 uprooted something more helpful to humanity has been planted. 

 When rightly understood, we see that this freer life of thought has been 

 constructive and helpful, not merely iconoclastic. Man has once again 

 taken his high place in the world as the interpreter of nature, and as 

 investigation widens his comprehension of the laws of natural phe- 



