To acquire immunity to eloquence is of the utmost importance to the citizens of a democracy.

It is not what the man of science believes that distinguishes him, but how and why he believes it. His beliefs are tentative, not dogmatic; they are based on evidence, not on authority or intuition.

The fundamental principle in the analysis of propositions containing descriptions is this: Every proposition which we can understand must be composed wholly of constituents with which we are acquainted.

As for earthquakes, though they were still formidable, they were so interesting that men of science could hardly regret them.

There was, I think, never any reason to believe in any innate superiority of the male, except his superior muscle.

Literature is inexhaustible, with every book a homage to infinity

A man is rational in proportion as his intelligence informs and controls his desires.