NICOLAUS COPERNICUS 21 



but his prudence prompted him to withhold the publication of his 

 great work, "De Orbium Caelestium Revolutionibus/' until 1343. In 

 May of that year the first printed copy was laid on his death-bed. 



THE NEW IDEA OF THE UNIVERSE* 



I can well believe, most holy father, that certain people, when they 

 hear of my attributing motion to the earth in these books of mine, 

 will at once declare that such an opinion ought to be rejected. Now, 

 my own theories do not please me so much as not to consider what 

 others may judge of them. Accordingly, when I began to reflect upon 

 what those persons who accept the stability of the earth, as confirmed 

 by the opinion of many centuries, would say when I claimed that the 

 earth moves, I hesitated for a long time as to whether I should 

 publish that which I have written to demonstrate its motion, or 

 whether it would not be better to follow the example of the Pythag- 

 oreans, who used to hand down the secrets of philosophy to their 

 relatives and friends only in oral form. As I well considered all 

 this, I was almost impelled to put the finished work wholly aside, 

 through the scorn I had reason to anticipate on account of the newness 

 and apparent contrariness of my theory to reason. 



My friends, however, dissuaded me from such a course and ad- 

 monished me that I ought to publish my book, which had lain concealed 

 in my possession not only nine years, but already into four times the 

 ninth year. Not a few other distinguished and very learned men 

 asked me to do the same thing, and told me that I ought not, on 

 account of my anxiety, to delay any longer in consecrating my work 

 to the general service of mathematicians. 



But your holiness will perhaps not so much wonder that I have 

 dared to bring the results of my night labors to the light of day, 

 after having taken so much care in elaborating them, but is waiting 

 instead to hear how it entered my mind to imagine that the earth 

 moved, contrary to the accepted opinion of mathematicians — nay, 

 almost contrary to ordinary human understanding. Therefore I will 

 not conceal from your holiness that what moved me to consider 

 another way of reckoning the motions of the heavenly bodies was 



* Selections from the Introduction to De Orbium Caelestium Revolutionibus. 



