6i THE HISTORY OF BIOLOGY 



serve a certain purpose; if it is asked, for instance, why man has not long 

 ears like the donkey, which would give better hearing, the answer is that 

 man's ears are such as they are in order to enable him to wear a hat. And the 

 wise Creator has not only taken utility into consideration when making man; 

 He has even taken thought for human beauty, as may be seen in the distribu- 

 tion of hair on the face; the beard on the chin is a suitable adornment for a 

 man, while the growth of a beard on the nose would give to the countenance 

 a wild and barbaric appearance. But if the hair of the head is thus the work 

 of the Creator, the hairs on the arms and legs are the work of chance; they 

 are likened to self-sown weeds — the Greeks who went about with bare 

 arms and legs considered these hairs disfiguring and therefore removed 

 them. To such absurdities did Aristotle's theory of the finality of nature 

 gradually lead, its application no longer being guided by his own sober and 

 clear logic. However, the piety of Galen expresses itself in nobler and deeper 

 thoughts when he leaves anatomical details and proceeds to ethical problems. 

 There is a truly biblical tone about words such as these: "In my opinion 

 true piety consists not in sacrificing hundreds of beasts or offering quantities 

 of spices and incense, but in oneself knowing and learning about the wisdom, 

 power, and love of the Creator." Equally noble are the words with which 

 he exhorts his colleagues not to strive for profit, but to offer themselves to 

 the service of suffering humanity. In this Galen shows the same noble and 

 humane spirit as his lord and master, Marcus Aurelius, expressed in his Medi- 

 tations, and there is every indication that, like the latter, he lived as he 

 taught. 



Galen's anatomical investigations 

 But if Galen in his general conception of life thus stood on the border-line 

 between antiquity and the Middle Ages, he was as regards knowledge of 

 anatomical detail the foremost philosopher of the classical period, and as 

 such remained the undisputed authority in his own branch of learning up to 

 the Renaissance, and strictly speaking even up to the time when Harvey 

 discovered the circulation of the blood and thereby destroyed one of the 

 foundation-stones of his theoretical system. Both as an anatomist and as a 

 physician Galen had indeed the inestimable advantage of being able to build 

 upon the work of brilliant predecessors, but he also realized the importance 

 of his inheritance and considerably enhanced it by his own observations. 

 These he carried out exclusively on animals, both dead and alive, especially 

 apes, which he considered particularly suitable as material for investigation 

 of human anatomy. There is never any question of his dissecting human 

 bodies; the times had changed considerably since the days of Herophilus; 

 old superstitions had again been revived and governed men's minds. He 

 characteristically begins his enunciation of the anatomy of the human body 

 with the hand, the most useful of all organs — that whereby the soul effects 



