"LET no one when young delay to study philosophy, nor when he is
old grow weary of his study. For no one can come too early or too late to
secure the health of his soul. And the man who says that the age for philosophy
has either not yet come or has gone by is like the man who says that the age
for happiness is not yet come to him, or has passed away. Wherefore both
when young and old a man must study philosophy, that as he grows old he may be
young in blessings through the grateful recollection of what has been, and
that in youth he may be old as well, since he will know no fear of what is
to come. We must then meditate on the things that make our happiness, seeing
that when that is with us we have all, but when it is absent we do all to win it."
- Epicurus, c. 342-270 B.C.