Wisdom is not to be obtained from textbooks, but must be coined out of human experience in the flame of life.

The business of the philosopher is well done if he succeeds in raising genuine doubt.

The picture which the philosopher draws of the world is surely not one in which every stroke is necessitated by pure logic.

Let philosophy resolutely aim to be as scientific as possible, but let her not forget her strong kinship with literature.

Lastly, literature and philosophy both allow past idols to be resurrected with a frequency which would be truly distressing to a sober scientist.

Conservatism clings to what has been established, fearing that, once we begin to question the beliefs that we have inherited, all the values of life will be destroyed.

All logic texts are divided into two parts. In the first part, on deductible logic, the fallacies are explained; in the second part, on inductive logic, they are committed.