A corollary to Finagle's Law which seems to have almost infinite applications in writing comedy:
Never attribute to malice that which can be adequately explained by stupidity.
Ignorance of Hanlon's Razor is one of the more common forms of Genre Blindness. However, applying the Rule of Shades of Grey ("No rule is universally valid, including this one"), Hanlon's Razor is often stated this way:
Don't assume malice when stupidity is an adequate explanation. At least, not the first time.
Any sufficiently advanced incompetence is indistinguishable from malice.
This law relies on the assumption that ignorance in and of itself isn't malicious, which often doesn't fly in a court of actual law (either way, it still led to disaster, so it still needs to be punished). It also doesn't account for malicious actions taken to conceal ignorance, which is Truth in Television — the Blue Code of Silence.
In the war between Romanticism and Enlightenment, Hanlon's Razor is decidedly on the side of Enlightenment (if most bad things are the result of stupidity, incompetence, and ignorance, then one can make the future better through education and good design/idiot-proofing). Not to be confused with Occam's Razor, although the two can end up being invoked together; many Conspiracy Theories, for example, assume complicated scenarios based on malicious intent to explain things which the two Razors would prefer to attribute to simple events based on incompetence. See also No Delays for the Wicked.
Note that the phenomenon of Trolling, in all its forms, specifically contradicts this law (though trolling by design does adhere to Grey's Law).
Note: This does not mean that everyone who is wrong must be either stupid or evil. None of us bats a thousand, after all.
See also Poe's Law and Troll Fic.
Why Clovis ends up fearing that the Emperor will consider him to be disloyal if he finds out about C.C., despite Bartley's indication later on that they had no traitorous intentions against the crown.
Lelouch and C.C. and their combined role in what happens with Euphemia around episode 22. Even if he's a mastermind, he was still dumb in this case, and she hadn't been as forthcoming about what she knew about her previous contractors and Lelouch's extremely recent headaches when attempting to use Geass.
Suzaku and his role in what happens when Lelouch gets captured by Schneizel and Kanon after his allegedly "private" meeting with Suzaku.
Used in Angel Beats!, where the Battlefront assumes "Angel" is an emotionless tool of eradication when really she's just like the rest of them. People around her vanish because she tries to make them happy, which usually results in them attaining that which they missed in life. Also inverted later on when they succeed in getting a new student council president. They start off thinking he is a mindless "NPC", but he turns out to be a sadist intent on ruling that world with an iron fist.
Later, we find out Celestia's real reason is so she can spend some time with the mane six, who are the closest things Celestia has to friends.
Films — Animated
Finding Nemo operates on this trope; the otherwise friendly dentist believes he has actually rescued the lame Nemo from the dangers of the reef, when what he has actually done is tear him away from his loving father. Likewise, the main antagonist is a hyperactive little girl who simply doesn't realize that if she shakes a baggie with a little fish inside too hard, she'll kill the poor little fish inside. In both cases, it's simple ignorance at work rather than maliciousness.
In the movie, Samson and Sally, while the humans are hunting whales for food, Moby Dick states that "Mankind is not vicious, mankind is stupid!"
Films — Live-Action
In Cube, the left-wing doctor's assumption that the Cube is part of some maniacal government plot is immediately shot down by the revelation that it's just a senseless project that no bureaucrat had the cojones to pull the plug on. Which, once the truth sinks in, she admits is actually worse.
"It's a headless blunder masquerading as a master plan."
Both the 1951 and 2008 versions of The Day The Earth Stood Still have Klaatu admonish humans for being irresponsible, not outright malicious.
In Angels and Demons, the main character is standing in the Vatican vaults when the power is cut, killing the oxygen supply, and leaving him unable to breathe. He immediately assumes that someone was trying to kill him, but he is assured that the Vatican police (who were systematically cutting power to parts of the city to find a bomb's location) accidentally cut power to the grid that supplied the vaults, nearly suffocating him by mistake.
Most of The Coen Brothers' films are studies on human stupidity and the horrible things it causes to happen.
Tucker & Dale Vs. Evil runs on Hanlon's Razor, with each side thinking the other is murderous/suicidal lunatics, when it's all (until the final act) a series of deadly accidents and misunderstandings.
In Spaced Invaders, you have a group of Martians who while close to Earth on Halloween, overhear a broadcast of War of the Worlds. They end up mistaking it for an actual Martian war against Earth and proceed to join in the fight. Hilarity Ensues. In the end, a little girl named Kathy, who befriends them after discovering their mistake, summed it up best.
The Duumvirate bumps into this trope more than once. And they run the conspiracy.
Robert A. Heinlein's novella The Logic of Empire brings this up as two characters discuss how slavery and its equivalents are allowed to exist even though it's both immoral and economically self-defeating. One character says that it's a product of deliberate malice, and the other replies, "You have attributed conditions to villainy that simply result from stupidity."
See the Jargon entry, "Hanlon" may well have come from "Heinlein".
Black Beauty discusses this; after the teenage Joe Green's ignorant handling of a delicate situation nearly kills the eponymous horse, one character tries to defend him on the basis that he didn't mean any harm, but another responds harshly that ignorance has caused more far more evil in the world than actual malice.
In James Herbert's Domain, this trope and Government Conspiracy team up to backfire on the authorities, when a nuclear attack on London sends the government's elite scrambling for underground bunkers kept secret from the British public... only to find these bunkers are incompetently designed: easily cut off by rubble, flooded, and invaded by giant killer rats whose existence the bureaucrats had been covering up for years. Incompetence ultimately trumps malice, as the nuclear attack itself was a snafu: it ought to have been directed at China, not Britain.
This trope is mentioned in the Animorphs side story Visser. While recounting her past during a trial, Edriss notes that she had potentially discovered an ideal host species for the Yeerks, but was reassigned to a dead end position. She implies to her inquisitors that her rival Visser Three was responsible, but then notes to herself that it was more likely incompetence than conspiracy that led to her discovery being ignored.
From the Bible - "Have those who work evil no knowledge?" (Psalm 53:4), making this trope Older Than Feudalism.
Another: "Father, forgive them, for they know not what they do." (Luke 23:34). Granted, it was for malice they crucified Jesus. They just didn't understand the magnitude of their mistake.
Inverting this seems to be almost instinctual to the Skaven in Gotrek & Felix. Any time one of Grey Seer Thanquol's underlings screws up his plans, Thanquol often assumes it's because of a conspiracy to remove him from power. He also applies this to his "eternal enemies", the eponymous duo, as he believes they set out specifically to ruin his day. When he finally meets Gotrek and Felix face to face, they have no idea who he is!
About 90% of the plot of most Michael Crichton novels is a blend of this and really bad luck in the form of multiple worst case scenarios coming true, combining, and then mutating into something even worse. Very few characters in his novels are actually evil, they're mostly just lazy or short-sighted.
This is a Discussed Trope in Proven Guilty, where it is shown that practitioners of Black Magic almost always get involved in it due to not fully understanding the consequences of their actions, until they get too Drunk on the Dark Side to turn back. Harry specifically mentions that most "bad guys" never want to be bad guys, and often don't even realize that they are.
Live Action TV
Invoked on Buffy the Vampire Slayer as Harmony was the only person whose transformation into a soulless monster wasn't portrayed as tragic; objectively, it wasn't much of a change.
Invoked on That '70s Show when Charlie sees Kitty naked. Kelso advises him to walk in on Red naked: that way, Red will think he's an idiot rather than a pervert. It backfires when he accidentally walks in on Kitty naked again.
Better Off Ted: While Veridian Dynamics are indeed involved in projects of dubious moral character (killer pumpkins, the bunny that will "snuggle" everyone within a 5 mile radius, etc.), nearly every bad company policy or consumer product is "usually" done without any intentional malice. The episode Racial Sensitivity is probably the best invocation of the trope.
Veronica (after complaints about the separate water fountains for black employees): Okay, they realize it didn't work. Although there's a lot of fighting upstairs about whether it was the idea or the execution.
Discussed on The Daily Show during several skits in which the correspondents argue whether Fox News Channel's misleading reporting is due to them being evil or stupid. Wyatt Cenac and John Oliver represent "Team Evil" and "Team Stupid", respectively.
A weird variant of this in "The Daleks' Master Plan", where, although there is a Government Conspiracy, everyone in it is staggeringly incompetent. While running away from an assassin Mavic Chen sent, the Doctor and Steven run into a room where a teleportation experiment is taking place, and, due to the scientists not clearing the area, end up being accidentally blasted to the other end of the galaxy along with the MacGuffin. The Daleks constantly remind Chen of this for the rest of the story, asking him why he didn't stop scientific experiments on the station, but when they land on Mira they get sidetracked exterminating a bunch of lab mice that had also been teleported there because they aren't sure they aren't dangerous. Chen realises at this point that he's lost all control of the situation, and spends the rest of the story trying to convince the Daleks that he's still useful to them - mostly by trying to blame them for it - while becoming more and more stressed-out and unstable. Even when they find the Doctor in Ancient Egypt and draft a fellow Time Lord to fight him, everyone is so disorganised and out for themselves that the Doctor slips easily out of their clutches.
In gnostic beliefs, the Demiurge is considered the source of suffering in the world. Depending on the sects, this is either because he is deliberately malicious and arrogant, or because he is ignorant about the true nature of things, or a combination of both. Valentianism in particular is quite forgiving towards him, seeing his ignorance as pitiful or even innocent, and holds that he will eventually wise up.
Paranoia. As deadly as the world of Alpha Complex is, the real threats aren't those out to get you, but the whole incompetency of the system. The Friend Computer wants to help you, not kill you, but unfortunately it isn't able to do that properly. Shortsightedness, competing interests, and general incompetence destroy the world.
Double-whammy in Warhammer 40,000: on the one hand, your homeworld may be left to the predations of mind-shattering horrors simply because someone in the Imperial bureaucracy misfiled something and forgot your planet existed. On the other hand, if they did remember, they might order your world destroyed anyway because you've had contact with the aforementioned gribbly monsters. Inthissetting, there is malice and stupidity in abundance, which helps the body count climb ever higher.
The Umbrella Corporation in the Resident Evil franchise appears to be a generic Evil Corporation, what with its using the T-Virus to experiment and attempt to create biological weapons. More often than not, the constant outbreaks of Zombie plagues are the result of massive stupidity and recklessness. Half the notes you find are employees questioning why they're building research facilities so close to Raccoon City or why they're wasting time with inefficient bioweapons. In addition, Umbrella's bioweaponry is a side-effect of its founder's search for eternal life and power.
In Star Control II, the Slylandro Probes seem bent on deconstructing everything in the galaxy to create more probes. Why was this plague of Von Neumann probes unleashed upon creation? Answer: a programming bug. The Slylandro purchased the self-replicating probes for peaceful exploration. Wanting to learn as much as they possibly could, they innocently set the probes' program value for self-replicating to maximum. The result, the probes sought out ships and evidence of civilization and then immediately destroyed them for raw materials to make more probes. Hilarity Ensues.
Quoted directly in Deus Ex on one of Majestic 12's computer terminals.
In Portal Aperture Science may use human guinea pigs and have created the most malevolent, twisted AI in the history of their Earth, but it has been made painfully clear that they suffer from such staggering stupidity and way-out cloudcuckoolandthinking that there is no room for malice in their plans.
In Portal 2, this is often used by fans to describe Wheatley, though it may or may not be accurate in canon. After being in charge of the facility for a while, it's a bit unclear whether or not he's just going along with it to cover up how incredibly inept he is.
Whatever he may have become, Gla DOS is very clear that Wheatley was ingeniously designed to consistently make bad choices, to such a degree that the only times he does anything clever is when doing so would inadvertently make the situation worse or hasten his own downfall.
Aperture founder Cave Johnson embraces willful ignorance in the belief that all scientific discovery occurs by accident, which would be hindered by competence. Does his deliberate stupidity make him more evil or does such a belief make him more stupid?
"Never underestimate the ability of stupidity to catch you off guard and mess up humanity."
Sluggy Freelance in general could be considered a big example of Hanlon's Razor. Half the story arcs in the series wouldn't exist if it weren't for people making incredibly stupid decisions.
Though that particular example was a subversion, they thought the Ghouls were caused by some idiot unleashing a zombie plague, when in actuality the Ghouls were a Horde of Alien Locusts that had taken human form.
90% or more of the time a villain has done something right, it's because he or she, one of his or her underlings, or even one of the good/neutral guys has screwed up. A good number of the plots end with two characters thusly:
Sluggy Character: Why did you do ABCDGFQRS Xanatos Roulette? Seemingly Malicious Character: Because I wanted Y outcome. Sluggy Character: Why didn't you just do X action resulting Y outcome? Seemingly Malicious Character: Oh, duh. Nohardfeelingsseeyanever! *Exit*
In The Adventures of Dr. McNinja, Doc despised Monster Marty for years for seemingly selling out the Vigilante Club, but forgives him when he discovers that Marty did it because his monster form makes him dumb. This leads to the Aesop: "It's better for people to think that you're stupid, than to think you're a jerk."
In The Order of the Stick, Roy tells Miko that he had killed the evil lich Xykon. When she meets Xykon in the flesh (except, y'know, not), she immediately comes to the conclusion that Roy and the rest of the Order of the Stick are working for Xykon, and deceived her. The real explanation is that the Order didn't know how to destroy a lich: Xykon did get destroyed, but regenerated from his phylactery after the Order were long gone.
Miko's Lawful Stupid nature causes her to attribute anything to malice rather than incompetence, particularly since she embodies the Prosecutor's Fallacy in dismissing any explanation that doesn't fit her preconceived conclusion that Belkar Bitterleaf and everyone working with him is evil, evil, evil, despite evidence to the contrary showing that Belkar is just the Token Evil Teammate who's kept on a leash by the others. The ridiculous and paranoid theories she's forced to devise to hold to this viewpoint results in her invoking Grey's Law, when her willful ignorance that the Order of the Stick is not working for the bad guys becomes much, much more harmful to her homeland than any actual malice could have been. Murdering the city's ruler in the insane belief that he was working with Xykon because he was cooperating with Roy, who, as we all know, has to be evil, nearly murdering the ruler's heir because she assumes being proven wrong was just a test by the gods/a trick by Roy, and eventually stopping the founder of her order from defeating the villains and saving the city when her own incompetence leads her to destroy the stone he was guarding, killing her, saving the lives of the Big Bad and The Dragon, and dooming her homeland to Goblin occupation.
Belkar himself coasts the edge of this Razor constantly. When he's not one or the other, he's both.
A Crackedarticle on 9/11 conspiracy theories claims "There are basically two views on the subject, and I intend to provide both equally." Neither view supported in the article is that the conspiracy theorists are actually correct, so that leaves, "They're liars," or "They're stupid." At the end, the writer subverts it by suggesting that "Truthers" are both liars and mentally deficient.
South Park hung a biglampshaded on this trope in an episode debunking 9/11 Conspiracy Theories. The existence of conspiracy theories is actually a government conspiracy; Washington failed to prevent twenty Muslim lunatics with box cutters killing 3,000 people, so they'd rather allow people to believe that they made it happen — it actually makes the government look more formidable and in control than it is. They do this because the conspiracy theorists are going to ignore them when they try to tell the truth, so they might as well play to that crowd as well.
Megatron from The Transformers gives Starscream the opportunity to use this as a defense when they are betrayed by the Triple Changers, who then take over the Decepticons.
Megatron: You're either lying or stupid. Starscream: I'm stupid! I'm stupid!
Archer gets a lot of mileage out of "No, it was just incompetence." "And that makes it better?" "... Doesn't it?"
Everything surrounding World War I can be explained by the leaders of Europe acting like a bunch of gibbering morons. The fact that 4 years of horribly bloody conflict were kicked off because of a student with a pistol on a fortuitous lunch run boggles the mind. Europe in 1914 was a tangled web of treaties, ethnic tensions, and monarchical rivalries. To add to the mess, the war itself was, in all likelihood, inevitable: nobody had thought very hard when signing mutual defense treaties saying that "If any state declares war on X, we will declare war on that state." Hilarity, of a sort, Ensued when somebody actually finally did follow through with their treaty obligation to do just that, a dead guy's war plans went into effect automatically, and there's some evidence for the theory that the US was dragged in because some people in Europe felt that it wasn't fair to let the US stay out of the party. That probably counts as 'ignorance' of a sort, given that it could have easily enough backfired horribly.
A very controversial theory, put forward by the British historian A.J.P. Taylor, suggests that Adolf Hitler was not the evil scheming mastermind who had filed on his plans for world domination since the "Beer Hall Putsch" (as described in a certain piece of prison literature called Mein Kampf), but instead was a more or less buffoonish opportunist, who initially never thought of actually pulling through any of his ”world domination schemes" (i.e. the invasion of Austria, Czechoslovakia, Poland, France, Soviet Union, etc). According to Taylor, Hitler was a small fish in the big pond who got real lucky with his new title of "chancellor", and actually tried to weasel his way up as he swam with the stream, and that it was not until Britain and France had demonstrated their lack of stamina in enforcing the Versailles Treaty towards Germany that Hitler decided he could go even a step further and become more bratty. For instance, when he attempted to remilitarize the initially demilitarized Rhine area (whose demilitarization was in return surveilled by France). He sent over troops on bikes and horses, just in case the French retaliated and he needed to make a speedy retreat. When they didn't, he simply tested the patience of the Entente nations all the way to the invasion of Czechoslovakia and finally of Poland, when France and Britain finally declared war, realizing that they had missed too many opportunities to stand up to Germany rather than appease.
In contrast to the South Park entry above, conspiracy theories about 9/11 refuse to accept the possibility that any element, any tiny, inconsequential detail, is anything but the single thread that, if unraveled, will bring the whole conspiracy down into bite-sized chunks of truth.
Conspiracy theories in general depend on the assumption that a lack of evidence is in turn proof of a cover-up. Plain ol' incompetence with a dose of coincidence just doesn't seem like a cool enough explanation, apparently.
Nearly 50 years after his assassination, people are still coming up with harebrained theories about who "really" killed John F. Kennedy. Including one that postulates that the driver, who is clearly shown in the footage during the firing of the shot itself, was the real assassin. note Don't you see? He set up the perfect alibi! It's diabolical!
Less than 20 minutes after the accidental death of Diana, Princess of Wales, conspiracy theories were already buzzing around the Internet.
There was a movie made in the 1970s called The Lincoln Conspiracy. It was "Oswald didn't act alone", with Lee Harvey Oswald replaced by John Wilkes Booth. (And 2011's The Conspirator covers a specific aspect of the same story.) And then it turns out that in reality Booth actually was part of a conspiracy. It just turned out he was the only member of it who went through with the whole "murder another human being" aspect of the plan. His friend Lewis Paine stabbed the US Secretary of State but failed to kill him, and the other conspirator chickened out on shooting Vice President Andrew Johnson. All were eventually caught and hanged or imprisoned, except for Booth as he was shot by a soldier. Conspiracy theories claim he somehow escaped, it was a double kill, people in the US government were involved, etc.note The circumstances of Booth's death didn't help. Everton Conger (1834 - 1918) was the one leading the search for the assassin. He did manage to track him down and was trying to capture him alive, for obvious interrogation purposes. Sergeant Boston Corbett (1832 - 1894?) suddenly shot at Booth, fatally wounding him. Booth was never interrogated. Conger reported Corbett's actions to be "without order, pretext or excuse". There are suggestions that Corbett was acting to silence the assassin. Far more likely, though, that it was another of Corbett's insane moments. The guy had a long history of strange behavior, arguably starting with his self-castration in 1858. Supposedly to avoid sexual temptation. He ended up in an insane asylum by 1887. His biographers have noted that Corbett had spend years working as a hatter; his exposure to mercury may have much to do with his strange behavior. At the time, mercury was used in the production of felt, so hat makers tended to suffer from mercury poisoning due to the daily exposure. Thus the phrase "mad as a hatter". And the statements made by the doctor who examined Booth's body afterwards don't help, either. He made numerous notes of things that were mismatched to Booth's known medical records, including a missing scar from the removal of a tumor that the doctor performing the examination had himself done quite recently.
Glaciergate is said to be this: no actual attempt at deceiving was made, writers just made a rather stupid mistake and editors were likewise stupid in not catching it.
Ironically, this may in itself be due to ignorance of what is expected in the way of standard knowledge within the scientific community. The sloppy editing is particularly atrocious as both the editor and the author of the paper involved should have known that the original source was not one to cite as anything more than anecdotal, and only inside a grant application at that. (The grant in question could be summed up as "Please give me money to measure glaciers for a while and see if these rumors are true.")
The counter to this is that it was caught and pointed out by several reviewers, but not corrected, and the source cited was of a decidedly non-scientific value (it was a quote from a pop-article, not peer-reviewed in any form). The objections were that it shows gross negligence in the quality of the report, a "whatever sounds good" approach.
There's still some debate as to whether the Holodomor, the famine caused by Stalin's agricultural collectivization policies in the Ukraine, was the result of simple mismanagement or a deliberate genocide against a nation that had a (not undeserved) reputation as a breeding ground for counter-revolutionary sentiment. This isStalin — how this trope applies to totalitarian psychopaths is an interesting question.
The same is being debated about Mao's policies.
The same is being debated about every dictator's policies.
And indeed pretty much every modern famine.
A bit of self-aware humor in the US government is that the proof that there is no vast government conspiracy to cover up the existence of aliens is that such a conspiracy would rely on the idea that the US government is capable of doing anything with what resembles competence or discretion.
That leaves willful neglect as the simplest conspiracy hypothesis; all it's lacking is the notoriously elusive proof of intent.
Those Occidental Otaku who behave like such ("weeaboos"). You know the ones: they pepper their speech with gratuitous broken Japanese, they wear Cosplay even in places where it's not appropriate to do so, they center their existence on Anime, Manga, J Pop, and the like. In short, they are Straw Fans. While many other anime fans are inclined to simply write them off, or distance themselves from the fandom, it should be noted that the vast majority of the "weeaboos" don't act the way they do to deliberately be obnoxious. They do it because social skills take a long time to learn (and generally are not taught in classrooms), and because they have found something they simply latched onto that seems much more exotic and exciting than their day-to-day lives. Not that it makes their behavior or demeanor less annoying or upsetting, but at least it means that a) they most likely don't even know what they're doing is "wrong," and b) in a lot of cases, it can be corrected.
Not keeping this trope in mind is likely part of the problem for any community, moderator, administrator, or forum veteran that Suffers Newbies Poorly, especially when the community starts becoming insular. The tendency to suspect any potential social misstep or drama-causing on the part of the newcomer as trolling rather than simple ignorance or accident ends up deterring new individuals from joining as a result. Conservapedia and its administration, for instance, have demonstrated a history of treating edits or statements by new individuals that are not in line with the administration's stance on the topic as a deliberate provocation of the staff and respond with a prompt banning of the offending individual. The possibility of ineptitude or unfamiliarity by the newcomer are not considered as potential explanations—the administrative stance is that any explicit nonconformity to the administrative stance must stem only from malicious intent.
This trope should be kept in mind by anyone taking care of kids. Very young children may engage in dangerous or destuctive behavior simply because they don't know that what they're doing can have negative results.