You never know what motivates you.
The secret of getting ahead is getting started.
Be thine own palace, or the world's thy jail.
Go for it now. The future is promised to no one.
If you're going through hell, keep going.
The dog that trots about finds a bone.
Be gentle to all and stern with yourself.
If you've got a talent, protect it.
Begin to be now what you will be hereafter.
Always desire to learn something useful.
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.