One should not pursue goals that are easily achieved. One must develop an instinct for what one can just barely achieve through one’s greatest efforts.

No one does anything right in life, until they realize that they are making a mistake

A forced faithfulness is a bitter fruit for all concerned.

Gravitation is not responsible for people falling in love.

No, this trick won't work... How on earth are you ever going to explain in terms of chemistry and physics so important a biological phenomenon as first love?

It is only men who are free, who create the inventions and intellectual works which to us moderns make life worth while.

Those who have the privilege to know have the duty to act.