At fifteen, my mind was bent on learning.
At thirty, I stood firm.
At forty, I had no doubts.
At fifty, I knew the decrees of Heaven.
At sixty, my ear was receptive to truth.
At seventy, I could follow my heart's desires without sin.
Once I planned to write a book of poems entirely about the things in my pocket. But I found it would be too long; and the age of the great epics is past.
If you can keep your wits about you while all others are losing theirs, and blaming you. The world will be yours and everything in it, what's more, you'll be a man, my son.