OVERTHROW OF AUTHORITY IN SCIENCE 23 
spirits who see new truth with clearness, and have the bravery 
to force their thoughts on an unsympathetic public. 
The Beginning of Anatomy.—In order to appreciate his 
service it is necessary to give a brief account of his predeces- 
sors, and of the condition of anatomy in his time. Remem- 
bering that anatomy embraces a knowledge of the architec- 
ture of all animals and plants, we can, nevertheless, see why 
in early times its hould have had more narrow boundaries. 
The medical men were the first to take an interest in the 
structure of the human body, because a knowledge of it is 
necessary for medicine and surgery. It thus happens that 
the earliest observations in anatomy were directed toward 
making known the structure of the human body and that of 
animals somewhat closely related to man in point of struc- 
ture. Anatomical studies, therefore, began with the more 
complex animals instead of the simpler ones, and, later, 
when comparative anatomy began to be studied, this led to 
many misunderstandings; since the structure of man became 
the type to which all others were referred, while, of account 
of his derivation, his structure presents the greatest modif- 
cation of the vertebrate type. 
It was so difficult in the early days to get an opportunity 
to study the human body that the pioneer anatomists were 
obliged to gain their knowledge by dissections of animals, as 
the dog, and occasionally the monkey. In this way Aristotle 
and his forerunners learned much about anatomy. About 
300 B.c., the dissection of the human body was legalized in 
the Alexandrian school, the bodies of condemned criminals 
being devoted to that purpose. But this did not become 
general even for medical practitioners, and anatomy contin- 
ued to be studied mainly from brute animals. 
Galen.—The anatomist of antiquity who outshines all 
others was Galen (Claudius Galenus, 130-200 A.D.), who lived 
some time in Pergamos, and for five years in Rome, during 
