contradicting and disproving our opinion, is the very condition which justifies us in assuming its truth for purposes of action; and on no other terms can a being with human faculties have any rational assurance of being right.
When we consider either the history of opinion, or the ordinary conduct of human life, to what is it to be ascribed that the one and the other are no worse than they are? Not certainly to the inherent force of the human understanding; for, on any matter not self-evident, there are ninety-nine persons totally incapable of judging of it, for one who is capable; and the capacity of the hundredth person is only comparative; for the majority of the eminent men of every past generation held many opinions now known to be erroneous, and did or approved numerous things which no one will now justify. Why is it, then, that there is on the whole a preponderance among mankind of rational opinions and rational conduct? If there really is this preponderance—which there must be unless human affairs are, and have always been, in an almost desperate state—it is owing to a quality of the human mind, the source of everything respectable in man, either as an intellectual or as a moral being, namely, that his errors are corrigible. He is capable of rectifying his mistakes, by discussion and experience. Not by experience alone. There must be discussion, to show how experience