OVERTHROW OF AUTHORITY IN SCIENCE 27 



The historical association of Jacobus Sylvius with Vesalius 

 makes it of prime importance to do justice to his services to 

 anatomy, more especially since Vesalius made indiscriminate 

 criticisms of his teacher that have generally been accepted 

 without further testimony. Jacobus Sylvius evidently under- 

 stood what was essential to a reform in the teaching of anat- 

 omy, for, in his introduction to anatomy, he is very explicit 

 in advising that the study be pursued always by eye and 

 touch and primarily from the human body. He says that 

 anatomy can never be taught by reading and description. 

 Nevertheless, the limitations under which he labored, the 

 lack of sufficiently strong initiative, and the practical diffi- 

 culty of obtaining material, led him to teach the subject on 

 a lower level than he theoretically advocated. He read Galen 

 to his classes and the limited number of dissections in his 

 lecture room were made usually on the bodies of dogs by 

 unskilled barbers. With all these limitations, he helped 

 to elevate the standard of teaching anatomy in France, he 

 was very clear as an expounder of the subject, and he made 

 an important contribution in assigning special names to 

 muscles and bloodvessels. Galen had designated muscles 

 and other parts by numbers, while Vesalius gave them spe- 

 cific names, some of which are in use today. He was such a 

 worshipper of Galen that his method was essentially that of 

 authority and the progress of science awaited an innovator. 



Vesalius. Vesalius now came upon the scene; and 

 through his efforts, before he was thirty years of age, the idol 

 of authority had been shattered, and, mainly through his 

 persistence, the method of so great moment to future ages 

 had been established. He was well fitted to do battle against 

 tradition strong in body, in mind, and in purpose, gifted 

 and forceful; and, furthermore, his work was marked by 

 concentration and by the high moral quality of fidelity to 

 truth. 



