We must also suppose that before that time, the progress of reason will have gone hand in hand with progress in the arts and sciences; that the ridiculous prejudices of superstition will no longer cover morality with an austerity that corrupts and degrades it instead of purifying and elevating it. Men will know then that if they have obligations to beings who do not yet exist, these obligations do not consist in giving life, but in giving happiness. Their object is the general welfare of the human species, of the society in which people live, of the family to which they belong and not the puerile idea of filling the earth with useless and unhappy beings.

Marquis de Condorcet
The Future Progress of the Human Mind