20 HISTORY OF BOTANY 



Medicine with Botany, yet scientific treatment demands 

 that we should consider each separately. For the fact 

 is that in every art, theory must be disconnected and 

 separated from practice, and the two must be dealt 

 with singly and individually in their proper order before 

 they are united. And for that reason, in order that 

 Botany (which is, as it were, a special branch of Physics) 

 may form a unit by itself before it can be brought into 

 connection with other sciences, it must be divided and 

 unyoked from Medicine." The herbaUst was content 

 to arrange his plants in alphabetical order or according 

 to their " vertues." Caesalpino, on the other hand, 

 started with the idea that a system of classification could 

 be estabhshed on certain theoretical principles, and, after 

 meditating on these principles, he decided that the only 

 natural system must be founded on the reproductive 

 organs. The outcome was a series of groups in the 

 highest degree unnatural, embracing plants which, as 

 we now know, had not the sHghtest relationship to 

 each other. In his methods Caesalpino thus showed 

 himself an out-and-out Aristotelian. What Francis 

 Bacon wrote of Aristotle equally appHes to the Itahan 

 botanist. " For he had made up his mind beforehand ; 

 and did not consult experience in order to make right 

 propositions and axioms, but when he had settled his 

 system to his will, he twisted experience round, and made 

 her bend to his system ; so that in this way he is even 

 more wrong than his modern followers, the Schoolmen, 

 who have deserted experience altogether." 



Some strange notions on physiology appear here and 

 there in the De Plantis. Thus the chief function of 

 leaves is to protect young buds and fruits from air and 

 light ; plants having no senses are unable to hunt for 

 food, so they take it from the soil by suction ; since 

 plants need less food than animals they have no blood 

 vessels, and so on. His entire work is tinctured with the 

 strain of the Aristotelian philosophy, leading its author 



