One finds limits by pushing them.
Herbert Simon
Crave for a thing, you will get it. Renounce the craving, the object will follow you by itself.
Swami Sivananda
Who seeks shall find.
Sophocles
Always desire to learn something useful.
Do not weep; do not wax indignant. Understand.
Baruch Spinoza
To be wholly devoted to some intellectual exercise is to have succeeded in life.
Robert Louis Stevenson
Aim for the moon. If you miss, you may hit a star.
W. Clement Stone
Every exit is an entry somewhere else.
Tom Stoppard
Never give up, for that is just the place and time that the tide will turn.
Harriet Beecher Stowe
What you get by achieving your goals is not as important as what you become by achieving your goals.
Henry David Thoreau