Miguel de Unamuno Quote
And what is its moral proof? We may formulate it thus: Act so that in your own judgment and in the judgment of others you may merit eternity, act so that you may become irreplaceable, act so that you may not merit death. Or perhaps thus: Act as if you were to die tomorrow, but to die in order to survive and be eternalized. The end of morality is to give personal, human finality to the Universe; to discover the finality that belongs to it — if indeed it has any finality — and to discover it by acting.
The Tragic Sense of Life (1913) - XI : The Practical Problem