BOOK II. I. 3-ni. 6 



the termination of this process of thought, or as if, 

 assuming it possible to attribute this iiifinity of 

 nature to the artificer of the universe, that same 

 property would not be easier to understand in a single 

 world, especially one that is so vast a structure. 

 It is madness, downright madness, to go out of that 

 world, and to investigate what hes outside it just as 

 if the whole of what is within it were ah-eady clearly 

 known ; as though, forsooth, the measure of anything 

 could be taken by him that knows not the measure 

 of himself, or as if the mind of man could see things 

 that the world itself does not contain. 



II. Its shape has the rounded appearance of a skipeof 

 perfect sphere. This is shown first of all by the name ^" 



of ' orb ' which is bestowed upon it by the general 

 consent of mankind. It is also shown by the evidence 

 of the facts : not only does such a figure in all its 

 parts converge upon itself ; not only must it sustain 

 itself, enclosing and holding itself together without 

 the need of any fastenings, and withoiit experiencing 

 an end or a beginning at any part of itself ; not only 

 is that shape the one best fitted for the motion with 

 which, as will shortly appear, it must repeatedly * 

 revolve, but our eyesight also confirms this behef, 

 because the firmament presents the aspect of a 

 concave * hemisphere equidistant "^ in every direction, 

 which would be impossible in the case of any other 

 figure. 



III. The world thus shaped then is not at rest Jierohaim 

 but eternally revolves with indescribable velocity, """^ 

 each revolution occupying the space of 24 houi-s : 



the rising and setting of the sun have left this not 



' Medius properly denotes the position of the observer at 

 the centre, and is transferred to the circumference observed. 



