The first principle is that you must not fool yourself and you are the easiest person to fool.
Real knowledge is to know the extent of one's ignorance.
If you can't explain it simply, you don't understand it well enough.
I do not know how to teach philosophy without becoming a disturber of the peace.
My weapon is literature
The most savage controversies are those about matters as to which there is no good evidence either way.
The idea is to try to give all the information to help others to judge the value of your contribution; not just the information that leads to judgment in one particular direction or another.
It is beyond a doubt that all our knowledge begins with experience.
To read is to fly: it is to soar to a point of vantage which gives a view over wide terrains of history, human variety, ideas, shared experience and the fruits of many inquiries.
That men do not learn very much from the lessons of history is the most important of all the lessons that history has to teach.
For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled.
A cynic is a man who knows the price of everything, and the value of nothing.
A witty saying proves nothing.
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
Men are born ignorant, not stupid. They are made stupid by education.
Necessity is the mother of invention.
I have just three things to teach: simplicity, patience, compassion. These three are your greatest treasures.
Knowledge becomes evil if the aim be not virtuous.
There is one quality which one must possess to win, and that is definiteness of purpose, the knowledge of what one wants, and a burning desire to possess it.
Educate the children and it won't be necessary to punish the men.
Industrialize or perish.