Good disposition, favourable upbringing, association with pious and virtuous persons may contribute much towards such a propitious condition for our souls; but most securely are they grounded therein by good principles. I have already said that insight must be joined to fervour, that the perfecting of our understanding must accomplish the perfecting of our will. The practices of virtue, as well as those of vice, may be the effect of a mere habit, one may acquire a taste for them; but when virtue is reasonable, when it is related to God, who is the supreme reason of things, it is founded on knowledge. One cannot love God without knowing his perfections, and this knowledge contains the principles of true piety. The purpose of religion should be to imprint these principles upon our souls: but in some strange way it has happened all too often that men, that teachers of religion have strayed far from this purpose. Contrary to the intention of our divine Master, devotion has been reduced to ceremonies and doctrine has been cumbered with formulae. All too often these ceremonies have not been well fitted to maintain the exercise of virtue, and the formulae sometimes have not been lucid. Can one believe it? Some Christians have imagined that they could be devout without loving their neighbour,[53] and pious without loving God; or else people have thought that they could love their neighbour without serving him and could love God without knowing him. Many centuries have passed without recognition of this defect by the people at large; and there are still great traces of the reign of darkness. There are divers persons who speak much of piety, of devotion, of religion, who are even busied with the teaching of such things, and who yet prove to be by no means versed in the divine perfections. They ill understand the goodness and the justice of the Sovereign of the universe; they imagine a God who deserves neither to be imitated nor to be loved. This indeed seemed to me dangerous in its effect, since it is of serious moment that the very source of piety should be preserved from infection. The old errors of those who arraigned the Divinity or who made thereof an evil principle have been renewed sometimes in our own days: people have pleaded the irresistible power of God when it was a question rather of presenting his supreme goodness; and they have assumed a despotic power when they should rather have conceived of a power ordered by the most perfect wisdom. I have observed that these opinions, apt to do harm, rested especially on confused notions which had been formed concerning freedom, necessity and destiny; and I have taken up my pen more than once on such an occasion to give explanations on these important matters. But finally I have been compelled to gather up my thoughts on all these connected questions, and to impart them to the public. It is this that I have undertaken in the Essays which I