The worst offence of this kind which can be committed by a polemic, is to stigmatise those who hold the contrary opinion as bad and immoral men. To calumny of this sort, those who hold any unpopular opinion are peculiarly exposed, because they are in general few and uninfluential, and nobody but themselves feel much interest in seeing justice done them; but this weapon is, from the nature of the case, denied to those who attack a prevailing opinion: they can neither use it with safety to themselves, nor, if they could, would it do anything but recoil on their own cause. In general, opinions contrary to those commonly received can only obtain a hearing by studied moderation of language, and the most cautious avoidance of unnecessary offence, from which they hardly ever deviate even in a slight degree without losing ground: while unmeasured vituperation employed on the side of the prevailing opinion, really does deter people from professing contrary opinions, and from listening to those who profess them. For the interest, therefore, of truth and justice, it is far more important to restrain this employment of vituperative language than the other; and, for example, if it were necessary to choose, there would be much more need to discourage offensive attacks on infidelity, than on religion.