All our knowledge has its origins in our perceptions.

Nothing strengthens authority so much as silence.

Iron rusts from disuse; water loses its purity from stagnation… even so does inaction sap the vigour of the mind.

He who is fixed to a star does not change his mind.

Time stays long enough for anyone who will use it.

In rivers, the water that you touch is the last of what has passed and the first of that which comes; so with present time.

I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.

Learning never exhausts the mind.

People of accomplishment rarely sat back and let things happen to them. They went out and happened to things.