All religions are ancient monuments to superstition, ignorance and ferocity.

The unhappiness of people is due to their ignorance of nature.

All religious notions are uniformly founded on authority; all the religions of the world forbid examination, and are not disposed that men should reason upon them.

These principles, universally recognized, are at fault when the question of the existence of God is considered; what has been said of Him is either unintelligible or perfectly contradictory; and for this reason must appear impossible to every man.

Can theology give to the mind the ineffable boon of conceiving that which no man is in a capacity to comprehend? Can it procure to its agents the marvellous faculty of having precise ideas of a god composed of so many contradictory qualities?

It is thus religion infatuates man from his infancy, fills him with vanity and fanaticism: if he has a heated imagination it drives him on to fury; if he has activity, it makes him a madman, who is frequently as cruel to himself, as he is dangerous and incommodious to others: if, on the contrary, he be phlegmatic or of a slothful habit, he becomes melancholy and is useless to society.

In Nature nothing; is mean or contemptible, and it is only pride, originating in a false idea of our superiority, which causes our contempt for some of her productions. In the eyes of Nature, however, the oyster that vegetates at the bottom of the sea is as dear and perfect as the proud biped who devours it.