GROUNDS OF DISBELIEF. 193 



probability after it ; two different properties, the latter 

 of which is always a ground of disbelief; the former 

 is so or not, as it may happen. 



Many events are altogether improbable to us, be- 

 fore they have happened, or before we are informed of 

 their happening, which are not in the least incredible 

 when we are informed of them, because not contrary 

 to any, even approximate, induction. In the cast of 

 a perfectly fair die, the chances are five to one against 

 throwing ace, that is, ace will be thrown on an average 

 only once in six throws. But this is no reason against 

 believing that ace was thrown on a given occasion, if 

 any credible witness asserts it ; since although ace is 

 only thrown once in six times, some number which is 

 only thrown once in six times must have been thrown 

 if the die was thrown at all. The improbability, then, 

 or in other words, the unusualness, of any fact, is no 

 reason for disbelieving it, if the nature of the case 

 renders it certain that either that or something equally 

 improbable, that is, equally unusual, did happen. If 

 we disbelieved all facts which had the chances against 

 them beforehand, we should believe hardly anything. 

 We are told that A. B. died yesterday : the moment 

 before we were so told, the chances against his having 

 died on that day may have been ten thousand to one ; 

 but since he was certain to die at some time or other, 

 and when he died must necessarily die on some par- 

 ticular day, while the chances are innumerable against 

 every day in particular, experience affords no ground 

 whatever for discrediting any testimony which may be 

 produced to the event's having taken place on a given 

 day. 



Yet it has been considered, by Dr. Campbell and 

 others, as a complete answer to Hume's doctrine (that 

 things are incredible which are contrary to the uniform 



VOL. II. O 



