Obfuscating Stupidity

Everything About Fiction You Never Wanted to Know.
Advice for spies. And many others.
It is sometimes the height of wisdom to feign stupidity.
Cato the Elder
To be looked upon as a fool by an idiot is a true connoisseur's delight.
Georges Courteline

Also sometimes known as "playing dumb", a tactic whose effectiveness is predicated on characters convincing others they are complete oafs and therefore harmless. Acting like an ignorant hayseed, misinformed tourist, Handsome Lech or a Funny Foreigner is popular.

A variant of this, primarily found in teen comedies, is the popular student (almost invariably a girl) who acts like The Ditz in order to avoid being stigmatized as a Nerd; in such cases, the character may be wilfully ignorant, but inevitably faces a situation where she needs her native wits to escape a problem.

This differs from the Genius Ditz in that the latter is brilliant in a single field (or multiple obscure fields) but genuinely ditzy otherwise. Another variant is of someone who is a genuine genius but who pretends to be The Fool in order to avoid responsibility, either because they are lazy or because of some trauma which has undermined their confidence. May appear to be The Fool until the viewer realizes he's just so good at making intentional actions seem like total coincidences that it appears to be blind luck. If done well, you may not be able to tell if the character is an Almighty Janitor, a Crouching Moron, Hidden Badass or a Bunny Ears Lawyer. Or, for that matter, Too Dumb to Fool, especially if the character is good at noticing what is too obvious to be seen.

A favorite tactic of Tricksters. The opposite trope is Feigning Intelligence. See also the Old Master, to whom using this trope comes as natural as breathing; Covert Pervert, where the "stupidity" may be in reference to a particular subject; and Rich Idiot With No Day Job, a special case of this trope. See also Fauxreigner and Bilingual Backfire. Compare Obfuscating Insanity. Blondes may exploit the Dumb Blonde stereotype to help with the obfuscation. A Good Is Not Dumb character is often accused of using this trope.

This can backfire in a big way if the person using Obfuscating Stupidity needs people to trust him or her—only to realize that no one will believe the "idiot". Inversely, if other characters think the person is being obfuscating but he really is simple-minded, then he's a Seemingly-Profound Fool.

This is Older Than Feudalism, occurring in the Book of Genesis.

Related to Beneath the Mask. Compare Playing Drunk

No real life examples, please; we can never be sure whether stupidity is obfuscated or real.

Examples of Obfuscating Stupidity are listed on these subpages: