Absolute certainty is a privilege of uneducated minds and fanatics. - It is, for scientific folk, an unattainable ideal.

- Cassius Jackson Keyser

Mathematics, even in its present and most abstract state, is not detached from life. It is just the ideal handling of the problems of life.

- Cassius Jackson Keyser

The next-most difficult thing in the world is to get perspective. The most difficult is to keep it.

- Cassius Jackson Keyser

The present is no more exempt from the sneer of the future than the past has been.

- Cassius Jackson Keyser

The pursuit of excellence is the proper vocation of man.

- Cassius Jackson Keyser

If you ask ... the man in the street ... the human significance of mathematics, the answer of the world will be, that mathematics has given mankind a…

- Cassius Jackson Keyser

If people would stop objectifying abstractions (which they probably never will), or if they would stop objectifying the abstractions they make consci…

- Cassius Jackson Keyser

[The] humanization of mathematical teaching, the bringing of the matter and the spirit of mathematics to bear not merely upon certain fragmentary fac…

- Cassius Jackson Keyser

It is commonly, but erroneously, believed that it is easy to ask questions. A fool, it is said, can ask questions that a wise man cannot answer. The …

- Cassius Jackson Keyser