Red herring

A red herring is something that misleads or distracts from a relevant or important issue. It may be either a logical fallacy or a literary device that leads readers or audiences towards a false conclusion. A red herring might be intentionally used, such as in mystery fiction or as part of rhetorical strategies (e.g. in politics), or it could be inadvertently used during argumentation.

The origin of the expression is unknown. Conventional wisdom has long supposed it to be the use of a kipper (a strong-smelling smoked fish) to train hounds to follow a scent, or to divert them from the correct route when hunting; however, modern linguistic research suggests that the term was probably invented in 1807 by English polemicist William Cobbett, referring to one occasion on which he had supposedly used a kipper to divert hounds from chasing a hare, and was never an actual practice of hunters. The phrase was later borrowed to provide a formal name for the logical fallacy and literary device.

As an informal fallacy, the red herring falls into a broad class of relevance fallacies. Unlike the straw man, which is premised on a distortion of the other party's position, the red herring is a seemingly plausible, though ultimately irrelevant, diversionary tactic. According to the Oxford English Dictionary, a red herring may be intentional, or unintentional; it does not necessarily mean a conscious intent to mislead.

The expression is mainly used to assert that an argument is not relevant to the issue being discussed. For example, "I think we should make the academic requirements stricter for students. I recommend you support this because we are in a budget crisis, and we do not want our salaries affected." The second sentence, though used to support the first sentence, does not address that topic.

In fiction and non-fiction a red herring may be intentionally used by the writer to plant a false clue that leads readers or audiences towards a false conclusion. For example, the character of Bishop Aringarosa in Dan Brown's The Da Vinci Code is presented for most of the novel as if he is at the centre of the church's conspiracies, but is later revealed to have been innocently duped by the true antagonist of the story. The character's name is a loose Italian translation of "red herring" (aringa rosa; rosa actually meaning pink, and very close to rossa, red).

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Wikipedia