Slippery Slope Fallacy | Definition & Examples

The slippery slope fallacy is an argument that claims an initial event or action will trigger a series of other events and lead to an extreme or undesirable outcome. The slippery slope fallacy anticipates this chain of events without offering any evidence to substantiate the claim.

Slippery slope fallacy example
Person A: “I think we should lower the legal drinking age.”

Person B: “No, if we do that, we’ll have ten-year-olds getting drunk in bars!”

As a result, the slippery slope fallacy can be misleading both in our own internal reasoning process and in public debates.

What is the slippery slope fallacy?

Slippery slope fallacy occurs when a person asserts that a relatively small step will lead to a chain of events that result in a drastic change or a negative outcome. This assertion is called a slippery slope argument.

This is problematic as the person assumes a cause-and-effect relationship between two or more events or outcomes without knowing for sure how things will pan out. This progression of actions or events is presented as inevitable and impossible to stop (much like the way one step on a slippery incline will cause a person to fall and slide all the way to the bottom). However, little or no evidence is presented to back up the claim.

What is the slippery slope fallacy?

The slippery slope fallacy is a logical fallacy or reasoning error. More specifically, it is an informal fallacy where the error lies in the content of the argument rather than its format (formal fallacy). Therefore, not every slippery slope argument is flawed. When there is evidence that the consequences of the initial action are highly likely to occur, then the slippery slope argument is not fallacious.

Fallacious vs. non-fallacious slippery slope argument
Fallacious

“If I don’t pass tomorrow’s exam, I will not get the GPA I need to go to a good college, and then I won’t be able to find a job and earn a living. If I don’t pass the exam, my life is ruined!”

This is a fallacy because there is only an assumed connection between passing an exam and finding a good job. It’s an extreme conclusion that doesn’t logically follow.

Non-fallacious

“If I don’t pass tomorrow’s exam, this might affect my GPA, which in turn might impact my chances of going to a good college.”

Here, the slippery slope (A leads to B, B leads to C, etc.) is in the form of a logical extrapolation to a possible outcome. Therefore, it is not fallacious.

Why is the slippery slope fallacy used?

People use the slippery slope fallacy as a rhetorical device to instill fear or other negative emotions in their audience. It is often used to argue against a specific decision by adopting its (hypothetical) extreme consequences as if they were a certainty. This is a form of fearmongering (or appeal to emotion) that can be misleading because there is no proof that these extreme consequences will in fact materialize.

However, slippery slope arguments are not always negative or oppositional. It is possible to use a slippery slope argument to argue in favor of a proposition. In this case, they appeal to positive emotions like optimism. For example, “If we give everyone universal basic income, people will take the risk to set up their own businesses and ultimately turn into successful entrepreneurs.”

What are different types of slippery slope fallacy?

Different philosophers have classified slippery slope arguments in different ways. In general, there are three main types of slippery slope fallacies, depending on the type of erroneous argument at their core.

Causal slippery slope arguments

Causal slippery slope arguments suggest that a minor initial action or event will inevitably lead to a series of others, with each event or action being the cause of the next in the sequence.

Causal slippery slope fallacy example
“If we lower the voting age to sixteen years then fifteen-year-olds will also want to vote, and before you know it, babies will vote too!”

Precedential slippery slope arguments

Precedential slippery slope arguments claim that if we treat a minor case or issue in a specific way today, we will have to treat any major case or issue that may arise in the future the same way.

Precedential slippery slope fallacy example
“If we permit deadline extensions for students who need to prepare for a job interview, then we’ll have to start permitting that for other non-emergency reasons, like going on a holiday. Then, we might as well do away with deadlines since they won’t mean anything.”

Conceptual slippery slope arguments

Conceptual slippery slope arguments assume that because we cannot draw a distinction between adjacent stages, we cannot draw a distinction between any stages at all.

Conceptual slippery slope fallacy example
“There is no essential difference between 199 and 200 grains of sand or 200 and 201 grains and so on. Thus, there is no difference between 1 grain of sand and 3 billion grains of sand.”

Regardless of their form, slippery slope arguments are presented as a series of conditional propositions, such as “if A, then B” and “if C, then D,” the idea being that through a series of intermediate steps A implies D. Usually they start with a moderate claim and gradually escalate to an extreme end point with no possibility to stop in between.

Slippery slope fallacy examples

Advertisers resort to slippery slope fallacies when trying to sell us a number of everyday products.

Slippery slope fallacy examples in advertising

Slippery slope fallacy examples in advertising
The slippery slope fallacy is a common persuasion technique in advertising. By appealing to emotions such as fear or guilt, advertisers try to convince us that we have no choice but to buy their product or service.

Toothpaste commercials often rely on slippery slope arguments in the form of “if you don’t buy this toothpaste, you will get cavities and lose all your teeth.”

By presenting the worst-case scenario as the inevitable consequence of not buying that certain product, advertisers try to bypass logic and play on our fears. This is of course an irrational proposition, since it ignores all other factors that may affect our dental health.

Slippery slope fallacy examples in media

Interviews and debates on controversial topics are rife with slippery slope fallacies.

Slippery slope fallacy examples in media
Politicians who oppose same-sex marriage may deploy this tactic when asked why they believe what they do, offering arguments such as: “If we legalize same-sex marriage, what will stop us from legalizing marriage between humans and robots? Or humans and animals?” This is a fallacy because there is no logical proof that allowing same-sex marriage will inevitably lead to marriage between humans and objects or animals.

Using slippery slope arguments is often intentional so that the speaker avoids engaging with the issue at hand and instead shifts attention to its extreme hypothetical consequences. By equating the issue with its (hypothetical) negative consequences, the speaker tries to “win” the debate.

Other interesting articles

If you want to know more about fallacies, research bias, or AI tools, make sure to check out some of our other articles with explanations and examples.

Frequently asked questions about the slippery slope fallacy

Is a slippery slope argument always a fallacy?

A slippery slope argument is not always a fallacy.

  • When someone claims adopting a certain policy or taking a certain action will automatically lead to a series of other policies or actions also being taken, this is a slippery slope argument.
  • If they don’t show a causal connection between the advocated policy and the consequent policies, then they commit a slippery slope fallacy.
How do you respond to a slippery slope fallacy?

There are a number of ways you can deal with slippery slope arguments especially when you suspect these are fallacious:

  • Slippery slope arguments take advantage of the gray area between an initial action or decision and the possible next steps that might lead to the undesirable outcome. You can point out these missing steps and ask your partner to indicate what evidence exists to support the claimed relationship between two or more events.
  • Ask yourself if each link in the chain of events or action is valid. Every proposition has to be true for the overall argument to work, so even if one link is irrational or not supported by evidence, then the argument collapses.
  • Sometimes people commit a slippery slope fallacy unintentionally. In these instances, use an example that demonstrates the problem with slippery slope arguments in general (e.g., by using statements to reach a conclusion that is not necessarily relevant to the initial statement). By attacking the concept of slippery slope arguments you can show that they are often fallacious.

Sources in this article

We strongly encourage students to use sources in their work. You can cite our article (APA Style) or take a deep dive into the articles below.

This Scribbr article

Nikolopoulou, K. (2024, February 26). Slippery Slope Fallacy | Definition & Examples. Scribbr. Retrieved November 11, 2024, from https://www.scribbr.com/fallacies/slippery-slope-fallacy/

Sources

Jefferson, A. (2014). Slippery Slope Arguments. Philosophy Compass, 9(10), 672-680. https://doi.org/10.1111/phc3.12161

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Kassiani Nikolopoulou

Kassiani has an academic background in Communication, Bioeconomy and Circular Economy. As a former journalist she enjoys turning complex scientific information into easily accessible articles to help students. She specializes in writing about research methods and research bias.