understanding of moral and human subjects, that if opponents of all important truths do not exist, it is indispensable to imagine them and supply them with the strongest arguments which the most skilful devil’s advocate can conjure up.

To abate the force of these considerations, an enemy of free discussion may be supposed to say, that there is no necessity for mankind in general to know and understand all that can be said against or for their opinions by philosophers and theologians. That it is not needful for common men to be able to expose all the misstatements or fallacies of an ingenious opponent. That it is enough if there is always somebody capable of answering them, so that nothing likely to mislead uninstructed persons remains unrefuted. That simple minds, having been taught the obvious grounds of the truths