I am not afraid of tomorrow, for I have seen yesterday and I love today!

Even the knowledge of my own fallibility cannot keep me from making mistakes. Only when I fall do I get up again.

Challenging the meaning of life is the truest expression of the state of being human.

Rough diamonds may sometimes be mistaken for worthless pebbles.

There is no influence like the influence of habit.

Nothing can be done except little by little.

The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes.

Silence is the sleep that nourishes wisdom.

Have patience. All things are difficult before they become easy.

It is harder to conceal ignorance than to acquire knowledge.