33$ ON THE ULTIMATE 



sufficient reason of existence cannot be found either in 

 any particular thing or in the whole aggregate and 

 series of things. Let us suppose that a book of the 

 elements of geometry existed from all eternity and that 

 in succession one copy of it was made from another, it 

 is evident that although we can account for the present 

 book by the book from which it was copied, nevertheless, 

 going back through as many books as we like, we could 

 never reach a complete reason for it, because we can 

 always ask why such books have at all times existed, 

 that is to say, why books at all, and why written in 

 this way. What is true of books is also true of the 

 different states of the world ; for, in spite of certain laws 

 of change, the succeeding state is, in some sort, a copy 

 of that which precedes it. Therefore, to whatever earlier 

 state you go back, you never find in it the complete 

 reason of things, that is to say, the reason why there 

 exists any world and why this world rather than some 

 other. 



You may indeed suppose the world eternal ; but as 

 you suppose only a succession of states, in none of which 

 do you find the sufficient reason, and as even any number 

 of worlds does not in the least help you to account for 

 them, it is evident that the reason must be sought else- 

 where. For in eternal things, even though there be no 

 cause, there must be a reason 3 which, for permanent 

 things, is necessity itself or essence 4 ; but for the series 

 of changing things, if it be supposed that they succeed 

 one another from all eternity, this reason is, as we shall 

 presently see, the prevailing of inclinations 5 which con- 



3 If a thing is eternal, it cannot have a cause in time ; but there 

 must still be some reason (other than a cause in time) for its 

 existence. Cf. Aristotle's airtov (which is wider than our 'cause') 

 and the German Grund. 



4 By * permanent things' is meant things that are not contingent, 

 and these, in Leibniz's language, are i possible' things = ' necessary ' 

 th ings = essences. Cf. Monadology, 40 and 43, notes 64 and 67. 



5 The sufficient reason of changing or contingent things is not 

 an absolute principle, whose opposite would be self-contradictory, 



