LEONARDO AND MODERN SCIENCE 77 



the literary studies of his youth were very poor. No teachers had 

 time to mould his mind and to pervert his judgment. The good 

 workman Verrocchio was perhaps his first philosopher, nature 

 herself his real teacher. He was bred upon the experiments of the 

 studio and of real life, not upon the artificialities of a mediaeval 

 library. He read more, later in life, but even then his readings, I 

 think, were never exhaustive. He was far too original, too im- 

 patient. If he began to read, some idea would soon cross his mind, 

 and divert his attention, and the book would be abandoned. Any- 

 how, at that time his mind was already proof against the scholastic 

 fallacies; he was able, so to say, to filter through his own experi- 

 ence whatever mediaeval philosophy reached him either in print 

 or by word of mouth. 



Neither do I mean to imply that all the schoolmen were dunces. 

 Far from that, not a few were men of amazing genius, but their 

 point of view was never free from prejudice; it was always the 

 theological or legal point of view; they were always like lawyers 

 pleading a cause; they were constitutionally unable to investigate 

 a problem without reservation and without fear. Moreover, they 

 were so cocksure, so dogmatic. Their world was a limited, a closed 

 system; had they not encompassed and exhausted it in their 

 learned encyclopaedias? In fact they knew everything except their 

 own ignorance. 



Now the fact that Leonardo had been protected against them 

 by his innocence is of course insufficient to account for his genius. 

 Innocence is but a negative quality. Leonardo came to be what 

 he was because he combined in himself a keen and candid intelli- 

 gence with great technical experience and unusual craftsmanship. 

 That is the very key to the mystery. Maybe if he had been simply 

 a theoretical physicist, as were many of the schoolmen (their 

 interest in astronomy and physics was intense), he would not 

 have engaged in so many experiments. But as an engineer, a 

 mechanic, a craftsman, he was experimenting all the while; he 

 could not help it. If he had not experimented on nature, nature 

 would have experimented on him; it was only a choice between 



