A true knowledge of ourselves is knowledge of our power.
Every faculty and virtue I possess can be used as an instrument with which to worry myself.
When we are afraid we ought not to occupy ourselves with endeavoring to prove that there is no danger, but in strengthening ourselves to go on in spite of the danger.
It is possible by long-continued practice, not merely in lying, but in talking on subjects in which we have no real interest, not to know when we are sincere and when we are not.
There is always a multitude of reasons both in favor of doing a thing and against doing it. The art of debate lies in presenting them; the art of life lies in neglecting ninety-nine hundredths of them.