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 inherently fallacious ... 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 "Reverse Slippery Slope Fallacy", 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.)
Another related trope is Jumping Off the Slippery Slope, where a character quickly goes from doing something morally ambiguous to becoming clearly evil.
- DirectTV has 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, the fact this fallacy is used is the joke.
- Don't Copy That Floppy: Disk Protector uses it:
You say, "I'll just make a copy, for me and a friend"
Then he'll make one and she'll make one and where will it end?
One leads to another, then ten, then more
- In the dystopian comic Crowded, it has become commonplace to crowdfund assassinations on an app. A group of mansplaining nerds explain that it started out targeting only people who deserved it, corrupt politicians and businessmen who would usually be above the law. It worked too, making sure that politicians did their best to stay in their supporters good graces to not get a hit on their head. Then it trickled down to celebrities who tweeted something stupid, or directors who made bad sequels. That trickling down continued until people were ordering hits on their exes after a bad breakup or a neighbour who didn't trim their lawn. In this case, it is arguably a subversion because crowdfunded assassination is hardly a good thing even if the targets deserve it, and the cops In-Universe have tried to crack down on it, albeit futily.
- Andy Griffiths' Just Series: In "Busting" from "Just Stupid", Andy is having a Potty Emergency, but the men's bathroom is closed. He considers using the handicapped toilets, but then decides against it, for fear that the next day, he'll start maliciously using other things meant for disabled people.
- Played for Laughs in How Officer Pat Saved the Whole Town by Dr. Seuss. A policeman named Officer Pat is credited with saving the whole town just for simply killing a gnat, due to his reason for killing it. He reasoned that the gnat, if allowed to live, would bite the nearby cat, causing a series of events:
- First, the cat would allegedly wake up and meow, which would wake up some triplet babies, who'd cry and scare some birds, who would fly towards the man who runs the fish market.
- Then, the man would throw a fish into the air in surprise, the fish would land on a horse's nose, the horse would knock the pumpkins out of a cart it was pulling, the pumpkins would land on a man fixing a hydrant causing him to fall and break it, a woman would mistake it for rain and put up her umbrella, knocking a boy off his bike.
- Then, the boy would land on a ladder belonging to a house painter, who would spill paint and startle a woman into dropping her dishes, which would scare her dog, who'd jump into someone's horn.
- Finally, Pat thinks that if that happened, it would scare a man delivering dynamite by truck, causing him to crash his car and the town to explode.
- Nimona: This turns out to be the motive of the Big Bad. The Director of the knights of the kingdom disapproves of Ballister being knighted, as he is a commoner and all previous knights came from noble bloodlines. She reasons that he’ll be a weak link in the kingdom’s defense that will gradually grow as more commoners follow in his steps, and thus murders the queen and frames him for it.
- Spider-Man: Across the Spider-Verse: When Ganke Lee is asked by his roommate Miles Morales/Spider-Man to call the cops about an imminent robbery, he doesn’t bother and calls the request “a slippery slope.” His reasoning is that doing this one favor for Spider-Man would eventually result in Ganke doing more and more work for the superhero, and Ganke has no desire to be “your guy in the chair.”
- Animal House 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 all of American society in general. They then leave the room humming the national anthem.
- 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 on the amendment, Lincoln urges him 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?
- Pleasantville: The antagonist argues that people showing color will be the ruin of the town.
- The "no pen, no notes" category of jokes, which involve tiny mishaps that always lead to the same inevitable conclusion. The prototypical version goes: "Whatever you do, don't lose your pen. No pen = no notes. No notes = no education. No education = no degree. No degree = no job. No job = no money. No money = no food. No food = starvation. Starvation = death."
- Crazy Ex-Girlfriend: To rally a group of tenants to file a class action lawsuit against their landlord, Rebecca convinces them that the lack of hot water in their apartments will result in all their children becoming crack addicts.
- Everybody Hates Chris: This is Rochelle's justification for her strict (bordering on abusive) parenting: if their kids get away with a minor infraction, like lying or talking back, it will eventually lead them to do worse offenses until they eventually end up in a life of crime, like many of the inhabitants of Bed Stuy. In particular, when Tonya refused to eat sausages on dinner, she was venting how she'll eventually move from being a Picky Eater to choosing inappropriate clothing, then defying curfew, which would result in her getting pregnant, and punishes her by not allowing her to have anything else for dinner until she eats the sausage.
- Real Time with Bill Maher: 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."
- Sesame Street:
- In one episode, Telly refuses to try a cheese and lettuce sandwich, because he fears that if he did, he'd dislike the taste, scrunch his face up, lean back, fall off the stool, and come rolling down the street and crash into Lexine on her pogo stick, who'd fly off in land in Oscar's trash can.
- In one skit, Bert asks his roommate Ernie to put a vase on one of two shelves. Ernie thinks that if he put the vase on the small shelf, it'd fall off, break, and then Bert would throw him out of their apartment leaving Ernie homeless. He then decides that if he puts it on the big shelf, Bert would not only congratulate him for not breaking the vase, he'd throw him a party just for not breaking it.
- Another skit has Ernie deliberately not putting a roller skate away, because he thinks if Ernie stood on it, he'd be sent out the door to the ice cream shop, and then buy them both ice cream.
- Ernie again in a skit where he wants to ask a man named Herbert Birdsfoot to borrow a vacuum cleaner, but then decides not to, because he might be interrupting Herbert's bath, and then Herbert might catch a cold, get angry at Ernie, refuse to loan him the vacuum cleaner, and then badmouth him to Ernie's friends, who'd stop loaning him their things, and then stop speaking to him.
- One cartoon sketch has a little girl wanting to empty her bag of ping-pong balls, only to decide not to. Her reasoning was that the balls might wake up her pet cat, who'd knock over the parrot's cage, and then her mother would come home, assume the cat made the mess, and get mad at him.
- Another cartoon has a girl considering scaring her friend, who's on his skateboard and walking a dog. However, she changes her mind because she fears he may get pulled along by the dog on his skateboard, knock over the fruit cart, fall backwards, and hit his head.
- In another cartoon, a girl wonders what would happen if she lied that her cat Lucy broke the window when it was actually her. She decides not to when she thinks that "they" might punish Lucy by kicking her out of the house, she'd try to sleep in the doghouse of Bruno the dog, he'd get territorial, and she'd run away never to be seen again.
- Troper's Law 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 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.
- In "Don't Download This Song", "Weird Al" Yankovic says that if you download music (his own song being freely available on the Internet), you will become a hard case, robbing liquor stores and driving over people in your car.
- The last strip of the chapter "Futures Trading" in The Adventures of Dr. McNinja has the Doctor just having come back from an alternative future where homeless people were given jetpacks and hunted for sport. Thus, he's now explaining why jetpacks should never be invented because it will lead to that — even though the context in the future he just stopped from happening was that human-hating dinosaurs had taken over the world, and they were the ones doing the hunting. Then it turns out that the same slippery slope has already happened with rollerblades in this time.note
- Parodied in Saturday Morning Breakfast Cereal: "Commentary", where it's treated like a thought experiment in physics: "Imagine an idea placed at the top of a frictionless slope. Assume infinitely powerful gravity." (Even though this is purely metaphorical, it's stated in such strong metaphorical terms that it's also Exaggerated Trope.)
- Discussed in Chapter 6 of Strong Female Protagonist. Ex-superhero Allison, after using her Super-Strength to force an unwilling person into healing a friend, fears that compromising her ideals for the greater good has put her one step farther down the slippery slope to becoming a supervillain. Her philosophy professor, Gurwara, responds that she may be over-fearing it, and thereby blinding herself to previous times that she crossed a line. In his view, the real danger of the slippery slope fallacy is not the slippery slope itself, but its implicit claim to a person that they are at the top of the slope and have not already compromised.
- In the King of the Hill 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 Dream Sequence wherein George Washington, Abraham Lincoln, and Tom Landry (who all faced Slippery Slope crises on a much bigger scale) confront him, Washington quotes the trope directly.
- The Loud House: "Butterfly Effect" turns out to all be Lincoln imagining what would happen if he didn't tell Lisa the truth about breaking her chemistry set:
- First, he thinks that the explosion from the crash would lead to Lori discovering a photo of Leni with Bobby, causing her to think Bobby cheated on her and dump him for Clyde, and it would also give Leni a head injury that would make her smarter than Lisa, which would make Leni arrogant and she'd leave home.
- Then, he thinks Lisa would give up her studies in a fit of insecurity due to no longer being the smartest, leading to Lynn flunking due to Lisa no longer tutoring her, she'd throw a ball in frustration, which would hit Lola in the nose and disfigure it, making her insecure and she and Lynn would turn to crime.
- Then, Lana would worry that she'd also sustain an injury like Leni and Lola and move into a hamster ball, and Luna would write a song about the chaos, get famous, and go on a world tour. Luan, with no roommate, would take to watching the news, which would turn her into a jaded environmentalist.
- Finally, as part of her environmentalism, she'd let Lana's pets out of their cages, and her vampire bat would bite Lucy, turning her into a vampire, and Lincoln would go back to Lisa and Lily's room to try to fix the situation, only to find that Lily had drunk or inhaled Lisa's spilled formulae, causing her to grow into a giant and eat Lincoln.
- Used by Miss Finster in the 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!
- A number of pro-gun people in the U.S. debate over gun control seem to think that any form of restriction whatsoever will lead to the government confiscating all firearms.
- 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.
- 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 right out of The Handmaid's Tale 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, also ignoring the fact that these things happened before elective abortion was legal (there's no set correlation to these in places that have abortion on demand now either).
- 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.
- 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?
- 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 Armageddon, and any mention of Hitler or the Nazis.
- Atheism makes you a Straw Nihilist Omnicidal Maniac. This need not always be the case, however.
- Young Earth Creationists frequently use this for arguing that accepting evolution and that the Earth is millions of years old will lead you to question the rest of The Bible and lead you to atheism. Surprisingly, Richard Dawkins agrees with them in this sense.
- An inversion of sorts comes from the promoters of Atheism Plus like P.Z. Myers, who 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 "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 Creator Provincialism, 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.
- 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 The Daily Show 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.
- Often used to argue against laws banning hate speech. Free speech absolutists argue that if you deny free speech rights to Neo-Nazis, you must deny them to everyone. Legal precedents and constitutional provisions, however, can sometimes make this true.
- This can extend to companies flexing their muscles to remove someone who uses such fiery rhetoric. Of note is Alex Jones, whose Info Wars had been removed from various companies platforms through 2018. There were quite a few people who express worry that if someone like Pay Pal or YouTube could toss Alex Jones from their platforms, there are no practical barriers to stopping them from possibly outright tossing someone else out for being a Democrat or a Republican.
- Some take the argument even further, and claim that outright abuse and harassment should be protected by freedom of speech, and people who have been dropped from YouTube or social media platforms for their horrific behavior tend to brand the bans as media companies "censoring" them for their views.
- Frequently used in discussions regarding whether or not same-sex marriage should be legalized. Those opposed argue that allowing same-sex couples to marry will lead to similar laws allowing people to marry animals or underaged children (never mind that neither of them can give informed consent to a human adult, while gay adults can). Somehow the opposite (limiting marriage leads to a world where eventually nobody is allowed to marry anyone, such as interracial marriage or the marriage of infertile straight couples) is never addressed.
- There's a thought experiment that involves a cake that is baked with a tiny amount of raw sewage, equalling approximately 1% of it. Therefore, accepting any compromise means you're eating shit.
- Those who oppose queer rights will inevitably throw out these kinds of arguments. If you legalize gay sex, then how long until you legalize bestiality or incest? If you make gay marriage legal, how long until people start marrying dogs? If trans people be allowed in bathrooms, how long until pedophiles are allowed around children by claiming to be trans child? Obviously none of these things have happened; people point out that such arguments are recycled from earlier ones (e.g. civil rights for black people would mean they'd rape white people incessantly, accepting gays would greatly increase child sexual abuse, rinse repeat in regards to trans people etc).
- Some people claim that pushing for a fairer, more equal society will lead to a communist dystopia where everyone's forced to be exactly the same.
- Some opponents of the neurodiversity movement argue that accepting autism and ADHD will lead to widespread acceptance of conditions that really do have a correlation with harmful behaviour, such as malignant narcissism, pedophilia and homicidal tendencies.
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.
- The phrases "Where does it stop?" and "Where do you draw the line?" aren't always this fallacy. While they can be, if used to imply that there is no "line" or "stop," it can also be a legitimate question when it's ambiguous what a person or group's goals/standards are.
- In some cases of legal precedent; Eugene Volokh has written a paper about the slippery slope that analyzes examples where it can be valid.
Problems with pointing out the fallacy
- Just because sliding down the slope is not inevitable, does not make it impossible. Sliding down the slope may even be likely.
- Warning of the slippery slope can imply that one's position is currently at the top of the slope and has not already compromised.