"Mind you, I see the fallacy," he said. He liked the word. It was an honest admission of error.
-- George Friel, The Boy Who Wanted Peace, 1964
Because it has been his practice to listen to all that could be said against him; to profit by as much of it as was just, and expound to himself, and upon occasion to others, the fallacy of what was fallacious.
-- John Stuart Mill, On Liberty, 1859
Fallacy came to English in the 1300s from the Latin fallācia meaning "a trick."