You live and die according to ...

You live and die according to what goes on in yourself, which no one else can even begin to know, not even father, mother, wife, son, or daughter.
 William Saroyan

Quotes from the same author

Good people are good because they've come to wisdom through failure. We get very little wisdom from success, you know.
 William Saroyan
I'm not the kind of guy to knock at a door and then when the door is opened not go in.
 William Saroyan
The purpose of writing is both to keep up with life and to run ahead of it. I am little comfort to myself, although I am the only comfort I have, excepting perhaps streets, clouds, the sun, the faces and voices of kids and the aged, and similar accidents of beauty, innocence, truth and loneliness.
 William Saroyan
All comedians are people who really deeply consider the human experience not only a dirty trick perpetrated by a totally meaningless procedure of accidents, but an unbearable ordeal every day, which can be made tolerable only by mockery in one form or another.
 William Saroyan
Human greatness is a rather difficult thing to account for, and more often than not one is mistaken in one's hunches about somebody one has met.
 William Saroyan