 The majority of people’s errors, as we have already said elsewhere [i.e., on p. 9], depend more on reasoning based on false principles, than from reasoning incorrectly from their principles. We rarely allow ourselves to be misled by arguments that are defective merely because the conclusion is badly drawn. And those who could not recognize a fallacy by the light of reason alone would usually not be able to understand the rules behind it, much less to apply them. (Logic, 135; also see III.9, 157 and IV.20, 203)