In a word, Madam, I cannot too often repeat it, every system of religion appears to be designed for the utility of the priests; the morality of Christianity has in view only the interests of the priesthood; all the virtues that it teaches have solely for an object the church and its ministers; and these ends are always to subject the people, to draw a profit from their toil, and to inspire them with a blind credulity. We ought, therefore, to practise morality and virtue without entering into these conspiracies. If the priests disapprove of those who do not agree with them, and refuse to award any probity to the thinkers who reject their injurious and useless notions, society, which needs for its own sustenance real and human virtues, will not adopt the sentiments nor espouse the quarrels of these men, visibly leagued together against it. If the ministers of religion require their dogmas, their mysteries, and their fanatical virtues to support their usurped empire, the civil government has a need of reasonable virtues, of an evident, and above all, of a pacific morality, in order to exercise its legitimate rights. In fine, the individuals, who compose every society, demand a morality which will render them happy in _this_ world, without embarrassing themselves with what only pretends to secure their felicity in an imaginary sphere, of which they have no ideas except those received from the priests themselves. The priests have had the art to unite their religious system with some moral tenets which are really good. This renders their mysteries more sacred, and lends authority to their ambiguous dogmas. By the aid of this artifice, they have given currency to the opinion that without religion there can be neither morality nor virtue. I hope, Madam, in my next letter, to complete the exposure of this prejudice, and to demonstrate, to whoever will reflect, how uncertain, abstract, and deceitful are the notions which religion has inspired. I shall clearly show, that they have often infected philosophers themselves; that up to the present time, they have retarded the progress of morality; and that they have transformed a science the most certain, plain, and sensible to every thinking man, into a system at once doubtful and enigmatical, and full of difficulties. I am, Madam, &c. LETTER XI. Of Human or Natural Morality.