With the fearful strain that is on me night and day, if I did not laugh I should die.

I know that I am intelligent, because I know that I know nothing.

Those who educate children well are more to be honored than they who produce them; for these only gave them life, those the art of living well.

Man is the only creature that refuses to be what he is.

Let us permit nature to have her way. She understands her business better than we do.