The planning fallacy occurs when we underestimate how long it will take us to complete a future task. Despite knowing that similar tasks have generally taken longer than planned, we hold overly optimistic expectations and believe that next time will be different. Because we make unrealistic plans, we often end up running out of time, money, or energy.
Planning fallacy exampleYou are preparing for your upcoming midterm paper and set aside just one week to finish it. Although similar assignments in the past took you more time than expected, you feel confident that one week is enough time.
However, as the days pass, you realize that the topic is rather complex and demands more research than anticipated. On top of that, you catch a cold and are less productive. With the deadline approaching, you struggle to finish your paper, realizing that your optimism caused you to miscalculate the time and effort needed for this assignment.
The planning fallacy can impact any type of task and lead to several issues, including missed deadlines, increased costs, and frustration for both individuals and organizations.
The appeal to pity fallacy occurs when someone attempts to persuade others by provoking feelings of guilt or pity. Instead of presenting factual information and evidence to support an argument, one may try to play on people’s feelings. However, this is a manipulative tactic because feelings of pity are usually irrelevant to the point being made.
Appeal to pity fallacy example“Could you please change my grade from D to C? I worked really hard for this assignment. I even pulled an all-nighter to finish on time, and my parents will be so disappointed!”
The appeal to pity fallacy is also known as argumentum ad misericordiam or argument from pity and can be observed in various contexts like marketing, political campaigns, and law.
Appeal to emotion fallacy occurs when someone tries to convince another person by evoking their feelings rather than providing evidence.
With the appeal to emotion fallacy, people accept a claim as true because they react emotionally to it. As a result, they focus on factors irrelevant to the question at hand, ignoring facts and logical reasoning.
Appeal to emotion fallacy exampleYour sibling is trying to convince you to let them eat the last piece of the dessert:
“Can I have the last piece of cake? You know how much I love it, and it’s been a tough day for me. I’ve had such a bad day, and this cake would just make me feel so much better. You don’t want me to be sad, right?”
Appeal to emotion fallacy (also known as argument from passion, argumentum ad passiones, or argument from emotion) is common in various contexts like advertising, law, and politics.
An either-or fallacy occurs when someone claims there are only two possible options or sides in an argument when there are actually more. This is a manipulative method that forces others to accept the speaker’s viewpoint as legitimate, feasible, or ethical. This type of black-and-white thinking often appears in political speeches, advertising, and everyday conversations.
Either-or fallacy example“You can either go with me to the party tonight or sit at home alone and be bored all night.”
The either-or fallacy is also known as the false dilemma fallacy, false dichotomy, or false binary.
A false cause fallacy occurs when someone incorrectly assumes that a causal relation exists between two things or events. This is an improper conclusion because either such a relationship does not exist or the evidence in support of it is insufficient.
False cause fallacy example“Every time I bring my umbrella with me, it rains. Clearly, if I leave it at home, there will be sunshine!”
This type of reasoning error can lead to superstitious beliefs about the causes of various phenomena and events, a poor understanding of reality, and an inability to address root causes of problems.
Ad populum fallacy refers to a claim that something is true simply because that’s what a large number of people believe. In other words, if many people believe something to be true, then it must be true.
Ad populum fallacy exampleYou’re at a bookstore browsing for books with a friend. Although you are an avid sci-fi reader, your friend picks up a memoir and tells you that you should read the book because it’s a bestseller.
This type of argument is often used when there is no real evidence to back up a certain claim. Ad populum fallacy (also called bandwagon fallacy, appeal to numbers, or appeal to popularity) can be found in advertisements, political speeches, and everyday discussions.
Appeal to authority fallacy refers to the use of an expert’s opinion to back up an argument. Instead of justifying one’s claim, a person cites an authority figure who is not qualified to make reliable claims about the topic at hand. Because people tend to believe experts, appeal to authority often imbues an argument with credibility.
Appeal to authority fallacy example“My favorite actor, who starred in that movie about a virus that turns people into zombies, said in an interview that genetically modified crops caused COVID-19. So I think that’s what really happened.”
Appeal to authority is commonly used as a persuasion technique in advertising, politics, and everyday discussions.
The no true Scotsman fallacy is the attempt to defend a generalization by denying the validity of any counterexamples given. By changing the definition of who or what belongs to a group or category, the speaker can conveniently dismiss any example that proves the generalization doesn’t hold.
No true Scotsman fallacy examplePerson 1: No Scotsman puts sugar in his porridge!
Person 2: But my friend Duncan likes sugar with his porridge.
Person 1: Yes, but no true Scotsman puts sugar in his porridge.
The word “Scotsman” can be replaced with any other type of group affiliation. The no true Scotsman fallacy often arises in discussions around political, social, and religious matters.
Begging the question fallacy is an argument where the conclusion is assumed in one of the premises. It is an attempt to prove something is true while simultaneously taking that same thing for granted. This line of reasoning is fallacious because the assumption is not justified by any evidence.
Begging the question fallacy exampleThe belief in God is universal. After all, everyone believes in God.
In the example above, the conclusion (the belief in God is universal) validly follows from the premise (everyone believes in God), but only because the conclusion is simply a rewording of the premise. Here, we assume in the premise what we supposedly prove in the conclusion. This is a faulty line of reasoning, because you cannot assume what you are trying to prove.
The false dilemma fallacy involves presenting a limited number of options as if they were the only options available. This forces people to choose between two extremes, even though there is a spectrum of possibilities in between. The fallacy is misleading and prevents honest debate.
False dilemma fallacy exampleEither you support this new legislation to give the police more power, or you want society to descend into chaos!
A false dilemma (or false dichotomy) is a common type of fallacy. It often appears in political speeches and advertisements, as well as informal everyday conversations. It is also known as the either or fallacy.
