STATEMENT OF LEIBNIZ S PHILOSOPHY 99 



bene fundata in contrast with the phenomena of dreams 

 or visions, which are phenomena pure and simple, not 

 having any proper bond or connexion. Phenomena bene 

 fundata may be distinguished from the phenomena of 

 dreams, inasmuch as the former are vivid, multiplex (i.e. 

 varied in their relations and capable of a variety of tests 

 or observations), and congruous or consistent both with 

 themselves and with the general course of life or 

 experience, which we find in other phenomena. The last 

 of these tests is the most satisfactory, especially when it 

 is supported by the testimony of other people who have 

 also applied it. ' But the most powerful proof of the 

 reality of phenomena (a proof which is, indeed, sufficient 

 by itself) is success in predicting future phenomena 

 from those which are past and present, whether the pre- 

 diction be founded upon the success, so far, of a reason or 

 hypothesis, or upon custom so far observed 1 .' In short, 

 phenomena bene fundata are distinguished from illusions, 

 inasmuch as they are not merely separate and discon- 

 nected, but held together in a system so that their ante- 

 cedents may be traced and their consequents deduced 2 . 

 And Leibniz goes so far as to add: 'Although this 

 entire life were said to be nothing but a dream, and the 

 visible world nothing but a phantasm, I should call this 

 dream or phantasm real enough, if we were never 

 deceived by it, when we use our reason rightly 3 .' On 



1 De Modo distinguendi phenomena realia ab imaginariis (E. 444 a ; 

 G. vii. 320). 



2 Can this be reconciled with the view that materia secunda is 

 a mere aggregate or collection ? 



3 Loc. cit. Of course it must be remembered that the 'reality' 

 attributed by Leibniz to phenomena bene fundata is entirely relative 

 to the illusoriness of ' pure ' phenomena, such as we have in 

 dreams, and is not to be confounded with the reality of substance. 

 Cf. Nouveaux Essais, bk. iv. ch. 2, 14 (E. 344 b ; G. v. 355) : * The 

 truth of the things of sense consists only in the connexion of the 

 phenomena, which must have its reason [ground], and that is 

 what distinguishes them from dreams ; but the truth of our 

 existence and of the cause of phenomena is of another kind, 

 because it establishes substances. . . . The connexion of the pheno- 

 mena which establishes truths of fact in regard to sense-objects 



H 2 



