Cruel persecutions and intolerance are not accidents, but grow out of the very essence of religion, namely, its absolute claims.

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.

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

Again, both literature and philosophy work by appealing to certain reigning idols.

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

Liberalism regards life as an adventure in which we must take risks in new situation, in which there is no guarantee that the new will always be the good or the true, in which progress is a precarious achievement rather than inevitability.

Inertia is the first law of history, as it is of physics.