130 THE HISTORY OF BIOLOGY 



after the lapse of several decades that humanity realized that here was a new 

 foundation on which to base the conception of the universe. This was, of 

 course, due partly to the fact that Newton himself remained in certain re- 

 spects at a somewhat antiquated point of view. Like Galileo, he was quite 

 aware, as he himself says, that it has not been possible to discover "the cause 

 of the qualities of gravitation from phenomena, and I form no hypotheses," 

 and he maintained that it was justifiable to conclude from the existence of 

 properties in those bodies which had been investigated the existence of the 

 same properties in all bodies. At the same time he was firmly convinced that 

 finality in nature presupposes a personal God as the Creator of the universe, 

 and even as the Maintainer of the whole, since the irregularities in the course 

 of the heavenly bodies must some time be adjusted through the personal 

 intervention of the Creator. The latter assumption, which induced Leibniz 

 to liken Newton's cosmic system to a clock which now and then had to be 

 regulated in order to go properly, testifies more clearly than any other factor 

 to that mixture of childlike innocence and intellectual keenness in Newton 

 which gives to the whole of his personality the character of old and new in 

 conjunction, such as is so often to be found in philosophers at the turning- 

 point in the scientific history we are here discussing. It was left to the eight- 

 eenth century entirely to shake off the traditional ideas of the structure of 

 the universe and in their place to create that theory of existence which has 

 been maintained ever since. The man who more than any other exerted a 

 decisive influence in this respect is usually, and rightly so, not counted a 

 scientist at all, yet he has in a greater degree than most aff'ected the progress 

 of science; that man was Voltaire. 



pRANgois Marie Arouet de Voltaire is one of the best-known and most 

 discussed figures in cultural history — uncritically vaunted to the skies by 

 his admirers, violently calumniated by his enemies. In the course of his long 

 life (1694-1778) he exercised, more than perhaps any other has ever done, a 

 purely cultural influence in every sphere of life. His literary, political, and 

 religious activities are universally known. As a man of letters of middle-class 

 origin he had acquired a name in Paris for his cleverness and love of opposi- 

 tion, when he was suddenly ordered by the Government to leave the country 

 and took refuge in England. After a three years' sojourn in that country 

 (172.6-9) he returned full of ideas which he had assimilated there, and de- 

 voted the rest of his life to making them known to the world. Among these 

 new conceptions were Newton's discoveries in physics and astronomy. By 

 combining these with a number of ideas gathered from Leibniz's speculations 

 he produced a theory of the universe which was not only purely mechani- 

 cal — that the Cartesian theory had already been — but which was also 

 based upon mathematically calculable facts and was therefore bound to work 

 with indisputable authority. He worked with indefatigable enthusiasm to 



