EVIDENCE OF UNIVERSAL CAUSATION. 117 



instances being accounted for by the number and 

 complication of the modifying causes, or by their 

 inaccessibility to observation. 



The progress of experience, therefore, has dissi- 

 pated the doubt which must have rested upon the 

 universality of the law of causation while there were 

 phenomena which seemed to be sui generis, not sub- 

 ject to the same laws with any other class of pheno- 

 mena, and not as yet ascertained to have peculiar 

 laws of their own. This great generalization, 

 however, might reasonably have been, as it in fact 

 was by all great thinkers, acted upon as a proba- 

 bility of the highest order, before there were sufficient 

 grounds for receiving it as a certainty. For, whatever 

 has been found true in innumerable instances, and 

 never found to be false after due examination in any, 

 we are safe in acting upon as universal provisionally, 

 until an undoubted exception appears ; ' provided the 

 nature of the case be such that a real exception could 

 scarcely have escaped our notice. When every phe- 

 nomenon that we ever knew sufficiently well to be 

 able to answer the question, had a cause on which it 

 was invariably consequent, it was more rational to 

 suppose that our inability to assign the causes of 

 other phenomena arose from our ignorance, than that 

 there were phenomena which were uncaused, and 

 which happened accidentally to be exactly those 

 which we had hitherto had no sufficient opportunity 

 of studying. 



5. It must, at the same time, be remarked, that 

 the reasons for this reliance do not hold in circum- 

 stances unknown to us, and beyond the possible range 

 of our experience. In distant parts of the stellar 

 regions, where the phenomena may be entirely unlike 



