96 INTRODUCTION 



inasmuch as this force is a potential activity, a force 

 which tends to realize itself, it is automatic or sponta- 

 neous, it contains within itself the principle of its future 

 conditions, it is an Entelechy. Thus every actual 

 material body is materia secunda, from which materia 

 prima is merely a mental abstraction \ Every complete 

 substance is materia prima + Entelechy, i. e. passivity + 

 activity. 



Now while materia prima, being abstract passivity, is not 

 to be regarded as real substance, materia secunda, inasmuch 

 as it is matter and is therefore extended and infinitely 

 divisible, is, on the other hand, not to be confounded 

 with individual substance. Materia secunda must con- 

 tain an entelechy, but is not identical with it. Materia 

 secunda is an aggregate of things : it is to be conceived as 

 quantitative, consisting of paries extra partes, and is thus 

 quite distinct from substance, which must be conceived 

 as striving force, i. e. under the relation of means to end 2 . 



1 Cf. Epistola ad R. C. Wagnerum (1710) (E. 466 a ; G. vii. 529) : 

 'The active principle is not attributed by me to bare matter or 

 maieria prima, which is merely passive and consists solely in O.VTL- 

 jvrria and extension ; but to body or clothed matter or materia 

 secunda, which contains in addition a primary entelechy or active 

 principle. . . . The resistance of bare matter is not activity, but mere 

 passivity, inasmuch as it has avTirvvta or impenetrability, by which 

 indeed it resists that which would penetrate it. but does not re-act 

 unless it has in addition an elastic force. This elastic force must 

 be derived from motion, and thus also from an active force super- 

 added to matter/ Also De Ipsa Natura (1698), 12 (E. 158 b ; G. 

 iv. 512) : ' Matter is understood as either materia secunda or materia 

 prima ; materia secunda is indeed a complete substance, but not a 

 merely passive one ; materia prima is merely passive, but is not 

 a complete substance ; and there must further be added to it a soul, 

 or form analogous to a soul, ivrt\cx* ia V "purr), that is a certain 

 effort or primary force of acting, which itself is an indwelling law, 

 imprinted by Divine decree.' It should be noted that the expres- 

 sion 'substance,' as here applied to materia secunda, is not to be 

 taken too strictly. Materia secunda is not so much substantia as sub- 

 stantiata. This is more clearly brought out in Leibniz's later 

 writings. See Monadology, note 2, and this Introduction, Part iii. 

 p. 98 note. 



" Cf. Lettre a Remand (1715) (E. 736 a; G. iii. 657): 'Strictly 

 speaking, materia prima is not a substance, but something in- 

 complete. And materia secunda (as, for instance, the organic body) 

 is not a substance, but for another reason : namely, because it is 



