It is well known that those who do not trust themselves never trust others.

A simple rule in dealing with those who are hard to get along with is to remember that this person is striving to assert his superiority; and you must deal with him from that point of view.

The goal of the human soul is conquest, perfection, security, superiority.

Play is a child's work and this is not a trivial pursuit.

There is no thing as a man who does not create mathematics and yet is a fine mathematics teacher. Textbooks, course material-these do not approach in importance the communication of what mathematics is really about, of where it is going, and of where it currently stands with respect to the specific branch of it being taught. What really matters is the communication of the spirit of mathematics. It is a spirit that is active rather than contemplative-a spirit of disciplined search for adventures of the intellect. Only as adventurer can really tell of adventures.

Courage is not an ability one either possess or lacks. Courage is the willingness to engage in a risk-taking behavior regardless of whether the consequences are unknown or possibly adverse. We are capable of courageous behavior provided we are willing to engage in it. Given that life offers few guarantees, all living requires risk-taking.

To all those who walk the path of human cooperation war must appear loathsome and inhuman.