The institution of religion exists only to keep mankind in order, and to make men merit the goodness of God by their virtue. Everything in a religion which does not tend towards this goal must be considered foreign or dangerous.
What is called happiness is an abstract idea, composed of various ideas of pleasure; for he who has but a moment of pleasure is not a happy man, in like manner that a moment of grief constitutes not a miserable one.
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
I have lived eighty years of life and know nothing for it, but to be resigned and tell myself that flies are born to be eaten by spiders and man to be devoured by sorrow.
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.