GENERAL PRINCIPLES 43 



The problem itself is left by him without any satisfactory 

 solution ; but his followers made a definite attempt to 

 solve it by the theory of 'Occasionalism/ in which they 

 developed a suggestion that had been made by Descartes 

 when he spoke of thinking and extended substance as 

 alike dependent on nothing but the 'ordinary co-operation ' 

 (concours ordinaire) or l assistance ' of God. The Occa- 

 sionalist theories varied to some extent, but in its most 

 consistent form the hypothesis is that God is the sole 

 real Cause, that finite substance has no power or activity 

 of its own, and consequently that the changes which take 

 place in soul and body are both directly produced by 

 God. Consequently on the occasion of the appearing 

 of a phenomenon in the one substance God produces 

 a corresponding phenomenon in the other. The two 

 phenomena are quite independent, except for the fact 

 of their contemporaneous production by God, the one 

 real Cause. 



Leibniz's pre-established harmony has sometimes been 

 regarded as merely another variety of Occasionalism, in 

 spite of his frequent criticisms of the Occasionalist theory. 

 And he has been accused of borrowing (without acknow- 

 ledgement) from the Occasionalist Geulincx the well- 

 known illustration of the two clocks which he uses 

 in explaining his pre-established harmony. But Dr. 

 Edmund Pfleiderer has clearly shown l that Leibniz, who 



1 Leibniz und Geulincx mit besonderer Besiehung auf ihr beiderseitiges 

 Uhrengleichniss (Tubingen, 1884). Zeller comes to the same con- 

 clusion. The illustration appears in a note to Geulincx's Ethica, 

 Tract, i. cap. ii. 2, note 19 ; Land's ed., vol. iii. p. an. Cf. Third 

 Explanation of the New System, note 3. The notes are not in the first 

 edition of the Ethica, and they do not seem to have been known to 

 Leibniz. He received the illustration from Foucher, who probably 

 arrived at it independently, not knowing that it was used by 

 Geulincx. Cf. E. 130 a ; G. iv. 488. 



L. Stein holds that Leibniz was unaware of the source of the 

 illustration, and may have considered it superfluous to assign any 

 special source for it, inasmuch as it was a universally used simile, 

 characteristic of the Cartesian school (a Schulbeispiel*). With other 

 references the illustration is used both by Descartes and by 

 Cordemoy. See Archivftir Geschichte d. Philosophic, i. 59. 



