NATURAL SCIENCE IN THE MIDDLE AGES 275 



philosopher Aristotle has often been exaggerated. In medicine they 

 recognized Galen as a greater authority than Aristotle. In astronomy 

 Ptolemy was their guide. In natural history they cited Pliny the Elder. 

 Indeed they used scores of other authorities than Aristotle. But had he 

 been their sole source of information, they would not have been without 

 interest in natural science, for Aristotle devotes much attention to that 

 field. He wrote not only on logic, ethics and metaphysics; but on 

 physics, animals, plants, minerals, the heavens, sleep and waking, gener- 

 ation and corruption, and so forth. Indeed, he was without much 

 doubt the greatest scientist of antiquity. 



Now the twelfth century had known only Aristotle's "Logic." 

 When his other works were brought from Spain and translated from 

 Arabic into Latin in the early thirteenth century, those devoted to 

 nature created even more of a furore than the others. The great Univer- 

 sity of Paris at first prohibited these newly discovered books in natural 

 philosophy. But it was impossible to check the rising tide of secular 

 and scientific learning. Another French university at Toulouse adver- 

 tised its readiness to teach these works of Aristotle on nature, and before 

 long the forbidden books were being freely taught at Paris itself. 



Paris's two leading theologians and commentators on Aristotle were 

 also recognized in their own day as great students of nature. Albertus 

 Magnus wrote on all the subjects that Aristotle had treated and added 

 much new information in his works on plants and animals. Thomas 

 Aquinas is usually thought of as a theologian; but when he died, the 

 University of Paris wrote to the Dominicans asking that his bones might 

 be sent to Paris for burial, and also requesting the transmission of 

 some books begun by him while at the university but not as yet com- 

 pleted upon his departure from Paris. What were these writings ; theo- 

 logical treatises, commentaries on the minor prophets, or manuals of 

 devotion ? None of these. They were a commentary on the philosopher 

 Simplicius ; another on Aristotle's treatise " The Sky and Universe " ; a 

 third on Plato's " Timaeus," a dialogue dealing with nature ; and finally, 

 a treatise on irrigation and mechanical engineering. 



Another erroneous notion concerning the middle ages is that nature 

 was studied chiefly in order to illustrate spiritual truth or to teach 

 moral lessons. The " Bestiary," a little manual about animals used by 

 the clergy for illustrations in their sermons, is often referred to as 

 typical of medieval science ; but one might as well judge modern science 

 by the lurid articles in the supplements of our Sunday newspapers. Far 

 more typical are the long encyclopedias in Latin prose which collected 

 all available information concerning the phenomena of nature, and 

 whose motive was rather a keen curiosity about the things of this world 

 than a desire merely to illustrate divine verities. It is true that one of 

 the earliest and briefest of these encyclopedists, Alexander Neckam, an 



