BIASED MISCONSTRUCTIONS The previous section dealt with fallacies that are primarily self-deceptions, and this section will add another group of the same sort. If a man rationalizes to his own advantage, he may incidentally beguile others into seeing things his way, but the principle operating to produce errors in his arguments is that he has already deceived himself. In the present group also there is a psychological precondition or bias on the part of the speaker, by which he genuinely deceives himself. If he deceives others, he does so incidentally.
The man who refuses to examine evidence against his friend because he "knows" his friend is honest, who praises the "industry" of the ants, who complains at the absence of ambition amongst a tribe of Indians, who gambles foolishly on mistaken notions of odds -- this is the man who forgets that circumstances alter cases. He gets hold of some quite intelligible concept and brashly misapplies it to situations it was never designed to cover. These misconstructions are interesting chiefly as illustrations of the protean ways bias can disguise itself.