Red Herring

A red herring is something that pulls attention away from the matter at hand. In a detective story it's the suspicious stranger who turns out to be innocent. In an argument it's the change of subject that sounds like a reply. In an investigation it's the striking clue that has nothing to do with the cause.

The phrase comes from the kipper, a herring cured with salt and smoke until it turns reddish brown and smells strongly. The figurative use is usually traced to an 1807 story by the English journalist William Cobbett, who described using a red herring as a boy to draw hounds off the scent of a hare. The tale was an allegory: Cobbett was scolding the press for being distracted by a false report of Napoleon's defeat. Claims that hunters really trained dogs this way are older and less certain.

In fiction, red herrings are a craft tool. Mystery writers plant decoy suspects and misleading clues so the reader has something to suspect besides the truth. The rules of the classic puzzle mystery demand that the real solution stay available, so the decoy must be plausible without being a cheat; see Fair-Play Mystery. A red herring is the reverse of Chekhov's Gun, and it works only because readers expect every prominent detail to matter. Stories also use narrators who steer attention themselves. A MacGuffin, a plot object everyone chases that turns out not to matter in itself, is a related device.

Stage magic relies on the same principle. A conspicuous gesture with one hand draws the eye while the other does the work, exploiting how little of a scene people actually take in.

In argument, a red herring is a fallacy of relevance: answering a different question from the one asked, often one that stirs stronger feelings. Common forms include attacking a position nobody holds, which is easier than the real one, and retreating from a bold claim to a modest one when challenged; see Motte and Bailey. Coded language that lets a speaker mean one thing while appearing to say another is a cousin. Refuting a distraction takes more effort than producing it.

Investigators meet red herrings without anyone planting them. Debugging is full of errors that look alarming but are unrelated to the failure, and an early vivid clue can anchor a whole search; see Anchoring Effect. Two things that move together may share a hidden cause instead of causing each other. Elaborate theories built from coincidences are, in effect, collections of red herrings followed with conviction.