This is a work that cannot be completed except by a society of men of letters and skilled workmen, each working separately on his own part, but all bound together solely by their zeal for the best interests of the human race and a feeling of mutual good will.

We do not know nature; causes hidden in her breast might have produced everything. In your turn, observe the polyp of Trembley: does it not contain in itself the causes which bring about regeneration? Why then would it be absurd to think that there are physical causes by reason of which everything has been made, and to which the whole chain of this vast universe is so necessarily bound and held that, nothing which happens, could have failed to happen,—causes, of which we are so invincibly ignorant that we have had recourse to a God, who, as some aver, is not so much as a logical entity? Thus to destroy chance is not to prove the existence of a supreme being, since there may be some other thing which is neither chance nor God—I mean, nature. It follows that the study of nature can make only unbelievers; and the way of thinking of all its more successful investigators proves this.

To say that man is a compound of strength and weakness, light and darkness, smallness and greatness, is not to indict him, it is to define him.

To prove the Gospels by a miracle is to prove an absurdity by something contrary to nature.

Scepticism is the first step towards truth.

Superstition is more injurious to God than atheism.

We are constantly railing against the passions; we ascribe to them all of man’s afflictions, and we forget that they are also the source of all his pleasures … But what provokes me is that only their adverse side is considered … and yet only passions, and great passions, can raise the soul to great things. Without them there is no sublimity, either in morals or in creativity. Art returns to infancy, and virtue becomes small-minded.

There is no good father who would want to resemble our Heavenly Father

The God of the Christians is a father who makes much of his apples, and very little of his children.

To attempt the destruction of our passions is the height of folly. What a noble aim is that of the zealot who tortures himself like a madman in order to desire nothing, love nothing, feel nothing, and who, if he succeeded, would end up a complete monster!