To live is not merely to breathe

To live is not merely to breathe, it is to act. It is to make use of our organs, our senses, our faculties, of all the powers which bear witness to us of our own existence. He who has lived most is not he who has numbered the most years, but he who has been truly conscious of what life is. A man may have himself buried at the age of a hundred years, who died from the hour of his birth. He would have gained something by going to his grave in his youth, if up to that time he had only lived.
(Rousseau, Emile)