222 THE MONADOLOGY 



9. Indeed, each Monad must be different from every' 

 other. For in nature there are never two beings which 

 are perfectly alike and in which it is not possible to find 

 an internal difference, or at least a difference founded 

 upon an intrinsic quality [denomination] 15 . 



10. I assume also as admitted that every created 

 being, and consequently the created Monad, is subject 

 to change, and further that this change is continuous 

 in each 16 . 



15 This is the principle of the ' identity of indiscernibles ' ; see 

 Introduction, Part ii. p. 36. Cf. Nouveaux Essais, bk. ii. ch. xxvii. 

 3 (E. 277 b ; G. v. 214). For Kant's criticism see Critique of Pure 

 Reason, Hartenstein, ii. 267 ; Eosenkranz, ii. 229 ; Meiklejohn's Tr., 

 p. 202. Probably the first statement of the principle is to be found 

 in the writings of Nicholas of Cusa (14,31-1464). He says that 

 4 there cannot be several things exactly the same [aequalia~}, for in 

 that case there would not be several things, but the same thing 

 itself. Therefore all things both agree with and differ from one 

 another.' (De Venatione Sapientiae, 23.) Cf. De docta ignorantia, iii. i : 

 'All things must of necessity differ from one another. Among 

 several individuals of the same species there is necessarily a 

 diversity of degrees of perfection. There is nothing in the universe 

 which does not enjoy a certain singularity, which is to be found in 

 no other thing.' His theories are full of suggestions of Leibniz. Cf. 

 Falckenberg, History of Modern Philosophy, English Tr.. pp. 20 sqq. 

 Reference may also be made to a very interesting article by Zimmer- 

 mann, Nicolaus Cusanus als Vorlaufer Leibnitzens (Wien. Akad. Sitsungs- 

 berichte, vol. 8, p. 306). There is no mention of Nicholas of Cusa in 

 any of Leibniz's philosophical writings ; but in a letter to the Acta 

 Eruditorum (1697) Leibniz refers to him as a mathematician (cf. 

 Dutens, iii. 345). Intrinsic qualities are those which things have 

 in themselves, e.g. figure, motion, &c., while extrinsic qualities are 

 those which arise from their relations to other things, e.g. their 

 being perceived, desired, &c. Cf. Port-Royal Logic, part i. ch. ii. 

 (Baynes's Tr. , p. 37) : ' There are some modes which may be called 

 internal, because they are conceived to be in the substance, as round, 

 square ; d,nd others which may be called external, because they are 

 taken from something which is not in the substance, as loved, seen, 

 desired, which are names taken from the actions of another and 

 this is what is called in the schools external denomination.' 



16 There is constant change in created substances, even though 

 there may appear to be no change. What appears to us as absence 

 of change is really a very small degree of change. We have here 

 an application of the Law of Continuity. 



