WHEN now I had for a long time reflected upon 

 the uncertainty that pervaded all the mathematical 

 results then existing as to the motions of the planets, 

 it began to be repellent to me that the philosophers 

 who would investigate with such extraordinary care 

 the most insignificant details of the course of the 

 heavenly bodies, should yet find no certain ground for 

 the movement of the World Machine. 



COPPERNICUS, De Revolutionibus : Introd. (1543). 



