It's always too early to quit.
To know oneself, one should assert oneself.
If you've got a talent, protect it.
Be gentle to all and stern with yourself.
Never complain and never explain.
Expect problems and eat them for breakfast.
You never know what motivates you.
Know or listen to those who know.
Things do not happen. Things are made to happen.
I can, therefore I am.
There is no single development, in either technology or management technique, which by itself promises even one order-of-magnitude improvement within a decade in productivity, in reliability, in simplicity.