!! '''The [[http://en.wikipedia.org/wiki/Slippery_slope Slippery Slope Fallacy]]''':

Based on the idea that an object placed at the top of a slippery slope will slide all the way to the bottom if given even a small nudge, the ''Slippery Slope Fallacy'' means arguing that even a small step taken in one direction will lead to some drastic consequence. This argument usually ignores the individual connections between events in favor of simply linking one event inevitably to another. However, this is not fallacious in and of itself after all, some slopes really are ''that'' slippery. It does, however, fall on the claimant to justify a logical, probable, and inevitable series of events. Without that, the argument has no meaning.

Note that this can approach a YMMV. A Slippery Slope argument that you agree with will seem more reasonable than one you disagree with.

There is also a "ReverseSlipperySlopeFallacy", namely the argument that since one has taken the first step down the slope without sliding to the bottom, it is clearly safe to take the next step. (Demonstration: smoking one cigarette won't get you hooked, or give you cancer. Nor will smoking a second cigarette. However, keep smoking cigarettes, and bad outcomes become increasingly likely.)
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!!! Examples:
* Dropping the atomic bombs on Japan. Many of the scientists were certain that using it would lead to an arms race and total destruction of civilization. We've done a pretty good job avoiding the second bit (albeit with a few close calls, some of which were '''far''' closer than people knew at the time), but they got the arms race bit right.
* Used frequently by politicians. Especially shows up around election time where voting for an opponent will usually be portrayed as resulting in a {{dystopia}} of some sort, usually authoritarian in nature.
* DarthWiki/TropersLaw is a reaction to a slippery slope argument commonly found on this very wiki. "If we do ''anything at all'' in a way similar to the way that Wiki/{{Wikipedia}} does it, we will become as restrictive and bureaucratic as Wikipedia is perceived." Of course, this does not address concerns that the site is becoming more restrictive and bureaucratic, only that it does not inevitably follow that any action in that direction will lead to a worst-case scenario.
* [[Series/RealTimeWithBillMaher Bill Maher]] rebutted this type of fallacious reasoning in one routine: "Gay marriage will not lead to dog marriage! When we gave women the vote we did not also have to give it to parakeets. When we freed the slaves we were not obligated to free the gerbils."
* Pops up a lot in the pro-choice/pro-life debate. Pro-choice people might say any restrictions on abortion will inevitably result in a theocratic Christian fundamentalist dystopia where women are used as breeding cattle even though this didn't happen in any of the Western democracies during the many decades when abortion was ''illegal''. Pro-life people, meanwhile, will proclaim that the legalization of abortion necessarily opens the door to eugenics, euthanasia, social Darwinism, and so forth.
* Quite frequently PlayedForLaughs, in which case the logical leaps necessary to get from root cause to end result will be intentionally amplified and exaggerated.
* Musical comedian Rob Paravonian had some fun with this in "Pushing Band Candy," his tale of how he built an empire out of selling candy bars for school band fundraisers. And really, once he went too far pushing the product and got himself expelled, what else could he become but a hardcore drug dealer?
* ''Film/AnimalHouse'' rather awesomely uses this argument in the scene where Otter convinces Dean Wormer that it is unethical to target the entire fraternity for the action of "a few sick and twisted individuals". He then claims that if they are going to blame his fraternity, then they should blame the entire fraternity system, and if they are going to blame the entire fraternity system, they should blame the entire American society in general. [[SugarWiki/MomentOfAwesome They then leave the room humming the national anthem.]]
* Parents often claim that lying will lead to becoming a criminal.
* This is generally accepted as one of the three prohibited taboos of academic debate (British Parliamentary Style at least), the others being the related [[ApocalypseHow Armageddon]], and any mention of [[GodwinsLaw Hitler or the Nazis]].
* In "Don't Download This Song", Music/WeirdAlYankovic says that [[DigitalPiracyIsEvil if you download music]] [[HypocriticalHumor (his own song being freely available on the Internet)]], [[DigitalPiracyIsEvil you will become a hard case, robbing banks and driving over people in your car]].
* UsefulNotes/{{Atheism}} makes you a StrawNihilist OmnicidalManiac. [[TheAntiNihilist This need not always be the case, however]].
** Young Earth Creationists frequently use this for arguing that [[http://www.answersingenesis.org/CreationWise/CW_Pages/0408.asp accepting evolution and that the Earth is millions of years old]] will lead you to question the rest of Literature/TheBible and lead you to atheism. Surprisingly, UsefulNotes/RichardDawkins agrees with them in this sense.
** An inversion of sorts comes from the promoters of Atheism-Plus like P.Z. Myers, who [[OpinionMyopia are baffled that many existing atheists who came to their lack of belief through rationality do not support the same social justice issues he does, like feminism]], to which he says "[[NoTrueScotsman Why bother being an atheist?]]" Never mind that they may have different social and political opinions, there being no necessary connection between them. Partly this is CreatorProvincialism, as atheists in the United States do tend to be left-wing. Countries with greater numbers of atheists have more even distribution on the political spectrum.
* [=DirectTV=] has [[Advertising/GetRidOfCable a series of advertisements]] that show a chain of events beginning with getting Cable instead of [=DirectTV=] and ending in something bad happening. While it ''does'' show a (somewhat) logical progression from each event to the next, none of the events described are either inevitable nor necessarily relevant to the viewer. (For example, having a bad day because of your cable company ''could'' result in the wrong guy getting convicted and coming after you for revenge, but only if you happened to be a defense attorney.) Of course, [[RuleOfFunny the fact this fallacy is used is the joke.]]
* ''TabletopGame/CardsAgainstHumanity'' {{invoke|dTrope}}s this with a two-white-card black card: "_____ is a slippery slope that leads to _____."
* Used often in the U.S. minimum wage strikes. Pundits frequently asked if the minimum wage was going to be raised by a few dollars per hour now, what was to stop it growing to absurd levels. This led to many parodies on ''Series/TheDailyShow with Jon Stewart'', especially when one anchor asked "Why not raise minimum wage to one hundred thousand dollars an hour?" Apparently there is no middle ground between less than three hundred dollars a week and four million.
* In the ''WesternAnimation/KingOfTheHill'' episode "Trans-Fascism", Hank has to struggle between the law and his morals when he and his pals start running a lunch truck that sold foodstuffs banned by the city council. He knows Arlen is enacting an unfair law that even the person who had suggested it in the first place now regrets, but knew he could well cause worse problems. In a DreamSequence wherein UsefulNotes/GeorgeWashington, UsefulNotes/AbrahamLincoln, and Tom Landry (who all faced Slippery Slope crises on a ''much'' bigger scale) confront him, Washington quotes the trope directly.
* Used by Miss Finster in the ''{{WesternAnimation/Recess}}'' episode "The Great Jungle Gym Standoff" to argue why they shouldn't give in to the kids' demands.
-->'''Miss Grotke''': Maybe the kids have a point. Maybe we should give them what they want. It's just a jungle gym.\\
'''Miss Finster''': Just a jungle gym? I always knew you were a troublemaker, Grotke. Give in to the jungle gym today and they'll want better food tomorrow. Soon they'll demand a longer recess and then more free reading time. Eventually, society will crumble and western civilization as we know it will come to an end!
* ''{{Film/Lincoln}}'': During the debate over passage of the Thirteenth Amendment, which would outlaw slavery in America, Representative Yeaman announces his opposition to the amendment, despite hating slavery, because he fears it would lead to further reform, such as letting all black people vote. Just before the vote, Lincoln urges him just before the vote on the amendment to focus on the singular issue of slavery and let the rest be debated about in its own time.
-->'''Yeaman''': What shall follow upon that? Universal enfranchisement? Votes for ''women''?
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!!! Looks like this fallacy but is not:
* If one ''does'' establish the chain of logical implications (or quantify the relevant probabilities).
* If it establishes that the progression ''is'' inevitable.
* In some cases of legal precedent; Eugene Volokh has written [[http://www.law.ucla.edu/volokh/slippery.htm a paper about the slippery slope]] that analyzes examples where it can be valid.
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!!! Problem with pointing out the fallacy
* Just because sliding down the slope is not inevitable, [[FallacyFallacy does not make it impossible]]. Sliding down the slope may even be likely.
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