FALLACIES IN GENERAL. 337 



omission it is exposed unprotected to the influence of 

 any species of apparent evidence which occurs spon- 

 taneously, or which is elicited by that smaller quantity 

 of trouble which the mind may be not unwilling to 

 take. As little is Bias a direct source of wrong con- 

 clusions. We cannot believe a proposition only by 

 wishing, or only by dreading, to believe it. The most 

 violent inclination to find a set of propositions true 

 will not enable the weakest of mankind to believe 

 them without a vestige of intellectual grounds, with- 

 out any, even apparent, evidence. It can only act 

 indirectly, by placing the intellectual grounds of belief 

 in an incomplete or distorted shape before his eyes. 

 It makes him shrink from the irksome labour of a 

 rigorous induction, when he has a misgiving that its 

 result may be disagreeable; and in such examination 

 as he does institute, it makes him exert that which is 

 in a certain measure voluntary, his attention, unfairly, 

 giving a larger share of it to the evidence which seems 

 favourable to the desired conclusion, a smaller to that 

 which seems unfavourable. And the. like when the 

 bias arises not from desire but fear. Although a 

 person afraid of ghosts believes that he has seen one 

 on evidence wonderfully inadequate, he does not be- 

 lieve it altogether without evidence; he has perceived 

 some unusual appearance, while passing through a 

 church-yard: he saw something start up near a grave, 

 which looked white in the moonshine. Thus every 

 erroneous inference, though originating in moral 

 causes, involves the intellectual operation of admitting 

 insufficient evidence as sufficient; and whoever was 

 on his guard against all kinds of inconclusive evi- 

 dence which can be mistaken for conclusive, would 

 be in no danger of being led into error even by the 

 strongest bias. There have been minds so strongly 



VOL. II. Z 



