It's always too early to quit.
Without hard work, nothing grows but weeds.
After a storm comes a calm.
The most effective way to do it, is to do it.
Only the educated are free.
By failing to prepare, you are preparing to fail.
Never complain and never explain.
What you do today can improve all your tomorrows.
Things do not happen. Things are made to happen.
Do not weep do not wax indignant. Understand.
The scientist is motivated primarily by curiosity and a desire for truth.
Science, almost from its beginnings, has been truly international in character. National prejudices disappear completely in the scientist's search for truth.