298 FALLACIES. 



any strong passion renders us credulous as to the existence of 

 objects suitable to excite it. 



But the moral causes of opinions, though with most per 

 sons the most powerful of all, are but remote causes : they do 

 not act directly, but by means of the intellectual causes ; to 

 which they bear the same relation that the circumstances 

 called, in the theory of medicine, predisposing causes, bear to 

 exciting causes. Indifference to truth cannot, in and by itself, 

 produce erroneous belief; it operates by preventing the mind 

 from collecting the proper evidences, or from applying to 

 them the test of a legitimate and rigid induction ; by which 

 omission it is exposed unprotected to the influence of any species 

 of apparent evidence which offers itself spontaneously, or 

 which is elicited by that smaller quantity of trouble which the 

 mind may be willing to take. As little is Bias a direct source 

 of wrong conclusions. 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 without any, even apparent, 

 evidence. It acts 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. 

 It operates, too, by making him look out eagerly for reasons, 

 or apparent reasons, to support opinions which are conform 

 able, or resist those which are repugnant, to his interests or 

 feelings; and when the interests or feelings are common to 

 great numbers of persons, reasons are accepted and pass 

 current, which would not for a moment be listened to in that 

 character, if the conclusion had nothing more powerful than 

 its reasons to speak in its behalf. The natural or acquired 

 partialities of mankind are continually throwing up philoso- 



