Be gentle to all and stern with yourself.
To know oneself, one should assert oneself.
Without hard work, nothing grows but weeds.
Know or listen to those who know.
It's always too early to quit.
After a storm comes a calm.
By failing to prepare, you are preparing to fail.
The dog that trots about finds a bone.
Always desire to learn something useful.
Either you run the day or the day runs you.
Imagination is as vital to any advance in science as learning and precision are essential for starting points.