fallacy

Deceptive or false appearance; that which misleads the eye or the mind.

• I no longer believe in happiness, because I see the fallacy of my first belief; and the examination which that induced, has shewn me the fallacy of all. Shew me a heart without its hidden wound.

An argument, or apparent argument, which professes to be decisive of the matter at issue, while in reality it is not; a specious argument.

• Baldridge also showed the "one molecule of blood," usually held to be the stimulus for attracting sharks, to be another common fallacy, since a molecule of blood does not exist.