The crank cannot be refuted, only dismissed.
Erring
Error is boundless.
Nor hope nor doubt,
Though both be groundless,
Will average out.
—Cunningham
Whatever the fanatic permits himself is a duty: whatever he denies himself is a crime.
A belief no fact can sink no fact can float.
The good cause that leads to bad outcomes may not be all that good a cause.
A very few rigorous social processes — scientific method, trial by jury — converge on truth reliably. Argument is not among them.
Intelligence, n. The ability to make more elaborate errors, with more plausible justifications.
Someone who understands politics is about as likely to set up as a pundit as someone who can predict the future is to set up as a psychic.
We have all of our ideas at second hand, except the ones we think original, which we have at fourth or fifth.
Primitive irrationality is to refuse to refer actions and sentiments to abstract principle; decadent irrationality is to insist on it.
Psychology begins by classifying people according to their conduct; then grows scientific, and deduces conduct from the classifications.