fallacy
FAL-uh-see
/ˈfæləsi/
A mistaken belief or a flaw in reasoning that invalidates an argument.
Refers specifically to errors in logical construction or unsound premises, not merely telling a lie.
The story behind the word. From Latin 'fallacia' (deceit or trick), which derives from 'fallere' (to trip up or deceive). It arrived in Middle English to describe misleading intellectual arguments designed to trip up opponents in debates.
Word relationships
- misconception: Misconception is an incorrect opinion, while fallacy often refers to a breakdown in logical structure.
- truth: Truth represents verifiable factual reality without logical defect.
Commonly confused with
- falsity: Falsity is the state of being untrue; a fallacy is a flaw in argument structure or reasoning.
Word family
- fallacious (adjective): Based on a mistaken belief or unsound logic.
- fallaciously (adverb): In a manner containing logical flaws.
Collocations
- logical fallacy
- sunk cost fallacy
- popular fallacy
- fallacy of thinking
Idioms & expressions
- flawed logic
Example sentences
- "Believing that expensive products are always higher quality is a common consumer fallacy." Philosophy
Memory hook
Fallacy sounds like 'false'—a argument built on a fallacy is bound to fall down. Fallacy = flawed logic that fails.
When not to use
Do not use as a direct synonym for 'lie' or 'deliberate deception'; a fallacy can be uttered in complete good faith.
Fun facts
- The famous 'gambler's fallacy' causes people to believe that if a coin lands on heads ten times, tails is 'due' next.
Related words
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