TRANSLATOR S INTRODUCTION XXX111 



career as the first teacher and thinker of Germany. 

 He confesses naively that he was not a success 

 as a tutor, and it may have been because his intel- 

 lectual energy, during that quiet period of deepening 

 and ripening thought, was so much absorbed in 

 working out his Cosmogony. The scientific con- 

 ditions of the time were most favourable to the 

 stimulation of original thinking upon this ultimate 

 and most difficult problem of physical science. 

 The great Continental mathematicians were all 

 gradually being won from Descartes and Leibnitz 

 to the Newtonian Philosophy, like the open-minded 

 but yet obscure Konigsberg student ; and the 

 Academies of Science at Paris, St. Petersburg, 

 and Berlin, with a noble rivalry, competed for 

 the honour of connecting the greatest names with 

 their work. Frederick the Great, stimulated by 

 his French models, and impelled by the happy 

 conviction that the political development could 

 only prosper if it went hand in hand with the 

 new movements of science, divided the energy of 

 his active mind between the promotion of scien- 

 tific work in Prussia and the political complications 

 which were bringing him anxiously to the verge of 

 the Seven Years' War. He had succeeded in per- 

 suading Euler to leave St. Petersburg and come 

 to Berlin in 1741, to reorganise his Academy of 

 Sciences ; and when the great mathematician re- 

 turned to St. Petersburg, on a pressing invitation 

 from the Empress Catherine II. in 1756 blind in 



