Theological religion is the source of all imaginable follies and disturbances. It is the parent of fanaticism and civil discord; it is the enemy of mankind.
We are intelligent beings: intelligent beings cannot have been formed by a crude, blind, insensible being: there is certainly some difference between the ideas of Newton and the dung of a mule. Newton's intelligence, therefore, came from another intelligence
It is with books as with the fires of our grates, everybody borrows a light from his neighbor to kindle his own, which in turn is communicated to others, and each partakes of all.
Animals have these advantages over man: they never hear the clock strike, they die without any idea of death, they have no theologians to instruct them, their last moments are not disturbed by unwelcome and unpleasant ceremonies, their funerals cost them nothing, and no one starts lawsuits over their wills.
The policy of man consists, at first, in endeavoring to arrive at a state equal to that of animals, whom nature has furnished with food, clothing, and shelter.
He who is involved in ecstasies and visions, who takes dreams for reality, and his own imagination for prophesy, is a fanatical novice of great hope and promise, and will soon advance to the higher stage and kill men for the love of God.
You see, Mademoiselle, I have experience, I know the world. To pass the time, why don't you ask every passenger to tell you his life's story? And if there is a single one among them who has never cursed his life, who has not often told himself that he was the unhappiest of men, then you may throw me overboard, headfirst!
Let us therefore reject all superstition in order to become more human; but in speaking against fanaticism, let us not imitate the fanatics: they are sick men in delirium who want to chastise their doctors. Let us assuage their ills, and never embitter them, and let us pour drop by drop into their souls the divine balm of toleration, which they would reject with horror if it were offered to them all at once.