CESALPINI 37 



did. But he was confident and over-emphatic. In the 

 dedication of his De Metallicis to the Pope we find a 

 passage which shows that though he claimed for himself 

 that liberty of opinion which the Catholic Church grants 

 to those in whose loyalty it has confidence, he made no 

 secret of his inclination to restrict scientific thought in 

 less orthodox teachers. He repudiates an unnamed 

 author because he held opinions contrary to the prin- 

 ciples of philosophy, and also as a man condemned 

 (explosus) by the church.^ 



Cesalpini's De Plantis gives a short account of plant- 

 physiology as understood by a Peripatetic philosopher 

 of the sixteenth century. We find a discussion of the 

 question whether the seat of life is difi*used or concen- 

 trated ; it is finally placed just where the stem and root 

 meet, a point which has neither morphological nor 

 physiological importance. The pith, we are told, is the 

 seat of innate heat ; this strange belief was founded on 

 the resemblance of the pith surrounded by a cylinder of 

 wood to a spinal cord enclosed by a vertebral column. 

 The flower is said to exist, partly to protect the young 

 fruit, partly of necessity, because the plant becomes 

 turgid with vapour. Plants have no sexes, because in 

 them the genitura is not distinct from the matei-ia. 

 The chief function of the leaves is to shade the buds. 



Cesalpini's system of plants has been praised by Ray 

 and Linnaeus. He threw over the tentative method 

 practised by L'Obel and others, in order to bring for- 

 ward a new and logical method of his own. The ancient 

 division into trees and herbs is of course respected, and 



^I suppose that the author aimed at was Bernardino Telesio, who had 

 attacked the doctrines of Aristotle, and tried to supersede philosophy by 

 methodical observation. His treatise De natura rerum jtixta projyria principia 

 lifyri II (Rome, 1.565) was condemned in the Index of Pope Clement VIII, that 

 very Pope to whom Cosalpini dedicated liis Dc MetallicU. 



