Again, how much of this alleged necessity of error, as alloy for the too pure metal of sterling truth, is to be explained by the interest which powerful castes or corporations have had in preserving the erroneous forms, even when they could not resist, or did not wish to resist, their impregnation by newer and better doctrine? This interest was not deliberately sinister or malignant. It may be more correctly as well as more charitably explained by that infirmity of human nature, which makes us very ready to believe what it is on other grounds convenient to us to believe. Nobody attributes to pure malevolence the heartiness with which the great corporation of lawyers, for example, resist the removal of superfluous and obstructive forms in their practice; they have come to look on such forms as indispensable safeguards. Hence powerful teachers and preachers of all kinds have been spontaneously inclined to suppose a necessity, which had no real existence, of preserving as much as was possible of what we know to be error, even while introducing wholesome modification of it. This is the honest, though mischievous, conservatism of the human mind. We have no right to condemn our foregoers; far less to lavish on them the evil names of impostor, charlatan, and brigand, which the zealous unhistoric school of the last century used so profusely. But we have a right to say of them, as we say of those who imitate their policy now, that their conservatism is no additional proof of the utility of error. Least of all is it any justification for those who wish to have impressed upon the people a complete system of religious opinion which men of culture have avowedly put away. And, moreover, the very priests must, I should think, be supposed to have put it away also. Else they would hardly be invited deliberately to abdicate their teaching functions in the very seats where teaching is of the weightiest and most far-spreading influence. Meanwhile our point is that the reforms in opinion which have been effected on the plan of pouring the new wine of truth into the old bottles of superstition--though not dishonourable to the sincerity of the reformers--are no testimony to even the temporary usefulness of error. Those who think otherwise do not look far enough in front of the event. They forget the evil wrought by the prolonged duration of the error, to which the added particle of truth may have given new vitality. They overlook the ultimate enervation that is so often the price paid for the temporary exaltation.