To discover the true principles of morality, men have no need of theology, of revelation, or of gods. They need but common sense. They have only to look within themselves, to reflect upon their own nature, to consult their obvious interests, to consider the object of society and of each of the members who compose it, and they will easily understand that virtue is an advantage, and that vice is an injury to beings of the species.

Superstition in All Ages: A Dying Confession (ed. 1910)