There is nothing more notable in Socrates than that he found time, when he was an old man, to learn music and dancing, and thought it time well spent.

Better know nothing than half-know many things.

If the facts don't fit the theory, change the facts.

Necessity is the mother of invention.

Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.

The highest activity a human being can attain is learning for understanding, because to understand is to be free.

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.

Education is a system of imposed ignorance.

If I could explain it to the average person, I wouldn't have been worth the Nobel Prize.

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

We could never learn to be brave and patient, if there were only joy in the world

No man's knowledge here can go beyond his experience.

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

The fullness of knowledge only comes through the awareness of ignorance.

The knowledge of all things is possible

Know what you are talking about.

Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours.

The most savage controversies are those about matters as to which there is no good evidence either way.

I had rather excel others in the knowledge of what is excellent, than in the extent of my power and dominion

To every action there is always an equal and opposite or contrary, reaction