To teach effectively a teacher must develop a feeling for his subject; he cannot make his students sense its vitality if he does not sense it himself. He cannot share his enthusiasm when he has no enthusiasm to share. How he makes his point may be as important as the point he makes; he must personally feel it to be important.

My method to overcome a difficulty is to go round it.

A GREAT discovery solves a great problem but there is a grain of discovery in any problem.

A mathematics teacher is a midwife to ideas.

An idea which can be used only once is a trick. If one can use it more than once it becomes a method.

To write and speak correctly is certainly necessary; but it is not sufficient. A derivation correctly presented in the book or on the blackboard may be inaccessible and uninstructive, if the purpose of the successive steps is incomprehensible, if the reader or listener cannot understand how it was humanly possible to find such an argument....

There exist a lot of questions that the fools can ask, and the intelligent cannot answer.