Imagination is vastly more important than intelligence.

My pacifism is not based on any intellectual theory but on a deep antipathy to every form of cruelty and hatred.

A theory is something nobody believes, except the person who made it. An experiment is something everybody believes, except the person who made it.

The only mistake in life is the lesson not learned.

Don't second guess the mistakes you've made, others will do that for you. Make things as simple as possible, but not simpler.

What good is a reputation not put to good use.

Everything you can imagine, nature has already created.