When I am attacked by gloomy thoughts, nothing helps me so much as running to my books. They quickly absorb me and banish the clouds from my mind.

What is now proved was once only imagined.

Common sense is the collection of prejudices acquired by age eighteen.

I prefer the company of peasants because they have not been educated sufficiently to reason incorrectly.

A cynic is a man who knows the price of everything, and the value of nothing.

If you can't explain it simply, you don't understand it well enough.

If I have seen further it is by standing on the shoulders of Giants.

What is freedom of expression? Without the freedom to offend, it ceases to exist.

Investigate, educate and organize.

What we know is a drop, what we don't know is an ocean.

Don't worry that children never listen to you; worry that they are always watching you.

Real learning comes about when the competitive spirit has ceased.

I do not know how to teach philosophy without becoming a disturber of the peace.

Technology is just a tool. In terms of getting the kids working together and motivating them, the teacher is the most important.

No power and no treasure can outweigh the extension of our knowledge.

Make it a rule never to give a child a book you would not read yourself.

Just because I don't care doesn't mean I don't understand.

All sciences are vain and full of errors that are not born of Experience, the mother of all Knowledge.

Know what you are talking about.

Physics is like sex: sure, it may give some practical results, but that's not why we do it.

I think that kids have a greater capacity for processing things than we give them credit for.