Courage, conviction and confidence.
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
A child educated only at school is an uneducated child.
The first principle is that you must not fool yourself and you are the easiest person to fool.
If you want the present to be different from the past, study the past.
It is what you read when you don't have to that determines what you will be when you can't help it.
The only true wisdom is in knowing you know nothing.
The knowledge of all things is possible
He who would learn to fly one day must first learn to stand and walk and run and climb and dance; one cannot fly into flying.
A cynic is a man who knows the price of everything, and the value of nothing.
Education is a system of imposed ignorance.
Those who fail to learn the lessons of history are doomed to repeat them.
Words can be like X-rays if you use them properly - they'll go through anything. You read and you?re pierced.
The delight of opening a new pursuit, or a new course of reading, imparts the vivacity and novelty of youth even to old age.
An investment in knowledge pays the best interest.
If help and salvation are to come, they can only come from the children, for the children are the makers of men.
Dare to think for yourself.
Imagination is more important than knowledge.
Investigate, educate and organize.
It is possible to fly without motors, but not without knowledge and skill.
The fullness of knowledge only comes through the awareness of ignorance.