The most evident difference between man and animals is this: the beast, in as much as it is largely motivated by the senses and with little perception of the past or future, lives only for the present. But man, because he is endowed with reason by which he is able to perceive relationships, sees the causes of things, understands the reciprocal nature of cause and effect, makes analogies, easily surveys the whole course of his life, and makes the necessary preparations for its conduct.
Each part of life has its own pleasures. Each has its own abundant harvest, to be garnered in season. We may grow old in body, but we need never grow old in mind and spirit. No one is as old as to think he or she cannot live one more year.
For while we are enclosed in these confinements of the body, we perform as a kind of duty the heavy task of necessity; for the soul from heaven has been cast down from its dwelling on high and sunk, as it were, into the earth, a place just the opposite to godlike nature and eternity. But I believe that the immortal gods have sown souls in human bodies so there might exist beings to guard the world and after contemplating the order of heaven, might imitate it by their moderation and steadfastness in life.