The starting point of all achievement is desire.

Climbing to the top demands strength, whether it is to the top of Mount Everest or to the top of your career.

All the darkness in the world cannot extinguish the light of a single candle.

Alone we can do so little; together we can do so much.

You are never too old to become younger!

To give real service, you must add something which cannot be bought or measured with money.

In winter, I plot and plan. In spring, I move.

We travel. Some of us forever. To seek other states, other lives, other souls.

The starting point of all achievement is desire. Keep this constantly in mind. Weak desires bring weak results, just as a small amount of fire makes a small amount of heat.

All thinking men are atheists.

Find out who you are. And do it on purpose.

I will never be by violence constrained to do anything.

Gratitude is an illness suffered by dogs.

Lack of direction, not lack of time, is the problem. We all have twenty-four hour days.

Listen to many, speak to a few.

Question with boldness even the existence of God; because, if there be one, he must more approve of the homage of reason than that of blindfolded fear.

When you believe in a thing, believe in it all the way, implicitly and unquestionably.

I discover myself on the verge of a usual mistake.

The greatest thing in the world is to know how to belong to oneself.

Duty does not require any person to submit to the destruction of his personal ambitions and the right to live his own life in his own way.

The fact that the great scientist believed in flying machines was the one thing that encouraged us to begin our studies.