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 is 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 favour of simply linking one event inevitably to another. However, this is not fallacious in and of itself... after all, some slopes 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.

Examples of Slippery Slope Fallacy include:

• 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.
• Used quite famously by Glenn Beck, and then parodied by Jon Stewart.
• Tropers Law is a reaction to a slippery slope argument commonly found on the TV Tropes wiki: "If we do anything at all in a way similar to the way that 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.
• Bill Maher rebutted this type of fallacious reasoning in a 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."
  • Except that almost immediately after the repeal of "Don't Ask, Don't Tell," Moral Guardians were not at all surprised at the introduction of a proposal for a bill that had entered Congress, which would allow for bestiality rights among troops. Of course, the bill was introduced by an opponent of gays serving in the military, which suggests trolling.
    • Since then efforts have been made in several jurisdictions to try and legalize incest, which would suggest that the trolls either deliberately or accidentally wandered straight into Poe's Law.
• One particular counter-argument that shows the absurdity of the slippery slope is to reverse it: e.g. "If we ban gay marriage, then we'll ban straight marriage as well!", as seen here. Perhaps it might be attractive to those who dislike straight marriage, but c'mon.
• Quite frequently Played for Laughs, in which case the logical leaps necessary to get from root cause to end result will be intentionally amplified and exaggerated.
• Once Anakin Skywalker tried to defy the principles of the Jedi in order to save his wife, he was just a step away from slaughtering children. At least that's how the "Only Siths Deal In Assolutes" Jedis played it.
  • To be fair to the prequel movies, Anakin's actions in Revenge of the Sith were presented as the end of a chain of increasingly bad decisions and not the beginning of one. Remember all those dead Sandpeople in movie 2?
• The 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?
• Animal House rather awesomely uses this argument in the scene where Otter convinces Dean Warner 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. They then leave the room humming the national anthem.
• A subversion is a common political strategy whereby an ambitious government will do enough of a violation to be irksome but not enough for any rivals to risk war over this particular violation. The total plan could indeed be to expand to the point where it would have caused a war if it happened at once. One possible example is noted in The Great Game where the Czars expanded into Central Asia enough to irritate natives as well as rival empires but not enough to cause a general war. An unsuccessful variation may under some interpretations be the prelude to World War II. In this case the Germans continuously made succeeding demands until they finally made one to many by first getting the British and France to guarantee Poland and then invading it.

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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 a paper about the slippery slope that analyzes examples where it can be valid.
• Paradoxically a literal statement that a slope is slippery ("This slope is slippery so there should be good skiing") because it is not an argument at all but an observation. Some slopes just happen to be slippery.