The true method of knowledge is experiment.

Give light and people will find the way.

Human behavior flows from three main sources: desire, emotion, and knowledge.

Every addition to true knowledge is an addition to human power.

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.