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Thinking Traps

16 sections · 10 pts/section

What Are Logical Fallacies?

Logical Fallacies

A logical fallacy is an error in reasoning. The argument may sound convincing. But something inside the logic is broken. Fallacies show up in everyday talk, writing, and media.

logical fallacy

An argument that sounds solid but has a broken step inside it.

Knowing fallacies helps you think more clearly, build stronger arguments, and make better decisions.

Ad Hominem

Ad hominem means attacking the person instead of their idea. It does not matter who said something. What matters is whether the idea is right or wrong.

ad hominem

Attacking who said something, not what they said.

“"You are a child. You don't understand how money works."”— Example 1 — Easy to spot

Being young does not make an idea about money wrong.

“"He was arrested once. Why listen to his ideas about justice?"”— Example 2 — Easy to spot

A past mistake does not cancel a person's point. The idea still needs to be answered.

A scientist argues for healthier school lunches. Someone says: 'She gets paid by a food company. We shouldn't trust her.' Is this ad hominem?

Yes. Her funding source is worth knowing — but it does not make her argument wrong on its own. The data and reasoning still need to be addressed. This one is harder to spot because the concern about funding sounds reasonable.

Straw Man

A straw man takes your idea and changes it. It makes it more extreme than what you said. Then it attacks that changed version. You never said the extreme thing.

straw man

Changing someone's argument into an easier version to attack.

“"I think we should eat less red meat." "So you want everyone to become vegetarian?"”— Example 1 — Easy to spot

Eating less is not the same as eating none. The response attacks a different idea.

“"Students should have more free time." "You want to cancel all classes?"”— Example 2 — Easy to spot

More free time is not the same as no school. The argument was twisted.

A: 'We should review our school's dress code. It may be outdated.' B: 'Some people want to get rid of all rules at school. That would be chaos.' Is B using a straw man?

Yes, but it is subtle. B never names A directly — they attack a vague 'some people' version of the idea. This makes it harder to notice. A was only talking about one policy, not all rules.

False Dilemma

A false dilemma shows only two choices. It says: pick one or the other. But most situations have more options than two. The other choices are hidden or ignored.

false dilemma

Pretending there are only two options when more exist.

“"You are either with us or against us."”— Example 1 — Easy to spot

Most people are somewhere in between — or outside the situation entirely.

“"You can have a career or a family. You cannot have both."”— Example 2 — Easy to spot

Many people manage both. This presents two extremes as the only options.

A school says: 'We can either cut arts classes or cut sports. There is no other way to save money.' Is this a false dilemma?

Yes — and it is easy to miss. Both options are real, so it sounds reasonable. But there are almost always more than two ways to reduce costs: smaller cuts across many areas, finding new funding, and so on. The two choices were presented as if nothing else exists.

Slippery Slope

A slippery slope says one small step will lead to a chain of bad outcomes. Each step follows the last. The end result is usually extreme. But the links in the chain are not proven.

slippery slope

Claiming one action will lead to extreme outcomes, without showing how.

“"If we let students use phones in class, soon no one will pay attention to anything."”— Example 1 — Easy to spot

Phone use may have effects — but jumping to 'no one pays attention ever' skips many steps.

“"If we lower the speed limit by 10 km/h, next they will ban all cars."”— Example 2 — Easy to spot

One policy change does not automatically lead to an extreme outcome.

A parent says: 'If my child skips homework once, they will start skipping every day, and eventually drop out of school.' Is this a slippery slope?

Yes — though it is easy to sympathize with. The concern is real. But skipping once does not guarantee dropping out. Each step in the chain needs its own evidence. This version is harder to spot because the worry comes from a caring place.

Appeal to Authority

This fallacy uses an expert's name to win an argument. But the expert may not be qualified in this area. Or experts in the field may disagree. A name alone does not prove something.

appeal to authority

Using an expert's name as proof, without checking if the expert is right.

“"A famous actor says this vitamin cures illness. It must work."”— Example 1 — Easy to spot

An actor is not a medical expert. Fame does not make something medically true.

“"This Nobel Prize winner in chemistry says vaccines are dangerous. So they must be."”— Example 2 — Easy to spot

The prize is in chemistry — not medicine. Being an expert in one field does not make someone an authority in another.

A doctor with 20 years of experience says a new diet works best. Is using this as proof an appeal to authority fallacy?

It depends. If the doctor is citing research and evidence, that is not a fallacy — it is how expertise works. But if the argument is only 'trust me because I have experience,' without data, it leans toward the fallacy. Authority matters most when backed by evidence.

Appeal to Popularity

This says something is true because many people believe it. But popular things can be wrong. History is full of ideas most people once accepted — and that later turned out to be false.

appeal to popularity

Claiming something is true because many people believe it.

“"Everyone is buying this product. It must be great."”— Example 1 — Easy to spot

Popularity does not mean quality. Many popular things have been recalled or disproven.

“"Most people in this town think the earth is flat. So it probably is."”— Example 2 — Easy to spot

The number of people believing something does not make it true.

A survey shows 80% of parents in a school prefer stricter homework. A teacher says: 'Clearly, stricter homework is the right approach.' Is this appeal to popularity?

Yes, subtly. Parent preference is relevant and worth knowing — but it is not proof that stricter homework leads to better learning. What most people prefer and what the evidence shows are two different questions.

Circular Reasoning

Circular reasoning uses its own conclusion as evidence. It goes in a loop. The argument does not bring in any new information. It just restates the starting point.

circular reasoning

Using the conclusion as proof of itself.

“"The rules say so, and the rules are right because the rules say so."”— Example 1 — Easy to spot

This loops back to the beginning. Whether the rules are right is what needs to be proven — not assumed.

“"This book is reliable because it says it is reliable."”— Example 2 — Easy to spot

The book's own claim about itself is not evidence.

Someone says: 'We know democracy is the best system because free societies, which are democracies, have proven to be the most successful.' Is this circular?

Yes, subtly. 'Free societies' and 'democracies' are used as the same thing without explanation. And 'most successful' is never defined. The argument assumes what it is trying to prove — without bringing in independent evidence. This version is hard to spot because it sounds historical.

Hasty Generalization

A hasty generalization draws a broad conclusion from too few examples. A small sample becomes a rule for everyone. The conclusion may be true in some cases. But it is not proven for all.

hasty generalization

Drawing a wide conclusion from too few cases.

“"I know two people from that city who were rude. People there must all be rude."”— Example 1 — Easy to spot

Two people cannot represent an entire city.

“"The last three times I flew, the flight was delayed. Airlines are always late."”— Example 2 — Easy to spot

Three flights are not enough to conclude that all airlines are always late.

A school surveys 12 students and they say they prefer online learning. A report says: 'Students prefer online learning.' Is this a hasty generalization?

Yes. Twelve students cannot represent all students, especially if the school has hundreds. The report should say 'some surveyed students' — not 'students' as a whole. This version is subtle because 12 people feels like data.

Red Herring

A red herring brings up an unrelated topic to distract from the real one. The new topic may be interesting. But it does not address what was actually being discussed.

red herring

Bringing up an unrelated point to change the subject.

“"Why are you worried about my grades? Some kids in this school fail every class."”— Example 1 — Easy to spot

Other students' grades do not change what is true about these grades. The topic shifted.

“"You say our company pollutes. But we donate a lot to charity!"”— Example 2 — Easy to spot

Charity and environmental practices are separate matters. The pollution question was not answered.

A politician is asked about rising housing costs. She answers: 'Our city has the lowest crime rate in the region. Families feel safe here.' Is this a red herring?

Yes. Safety is important — but it is a different topic from housing costs. The question was not answered. This version is harder to spot because the new topic sounds positive and relevant to life quality.

False Cause

False cause assumes that because one thing happened before another, it caused it. Two events in order does not mean one caused the other. There could be other reasons — or it could be a coincidence.

false cause

Assuming that because B followed A, A caused B.

“"I wore my lucky socks and we won the game. My socks made us win."”— Example 1 — Easy to spot

The timing is there — the cause is not.

“"Ice cream sales rise in summer. Drowning rates also rise in summer. So ice cream causes drowning."”— Example 2 — Easy to spot

Both are connected to hot weather — not to each other.

A city builds a new library. Over three years, test scores across the city rise. A report says: 'The library improved student performance.' Is this a false cause?

Possibly. The library may have helped — but many other things also changed in three years: teachers, curriculum, funding, home environment. The connection sounds logical, which makes this version hard to spot. More research is needed before naming any single cause.

Appeal to Emotion

This uses strong feelings instead of reasons. It tries to make you act from fear, guilt, or sadness — not from thinking clearly. Emotions are real and valid. But they are not a substitute for evidence.

appeal to emotion

Using feelings instead of evidence to support a claim.

“"If you don't donate right now, animals will suffer and die. Do you want that on your conscience?"”— Example 1 — Easy to spot

The cause may be real — but using guilt in place of evidence is the fallacy.

“"Think of the children. We cannot allow this law to pass."”— Example 2 — Easy to spot

Without explaining how the law affects children, this is emotion without argument.

A documentary ends with slow music and images of struggling families, then asks viewers to call representatives to oppose a trade deal. Is this appeal to emotion?

It can be. Emotional storytelling is not always a fallacy — stories can make data meaningful. But if the documentary never shows the actual terms of the deal or any evidence, and relies only on feeling to drive action, it is using emotion in place of argument. The style makes it hard to notice.

Tu Quoque

Tu quoque means 'you too' in Latin. It responds to a criticism by pointing out the same flaw in the critic. But someone else's behavior does not make the argument wrong. Two wrongs do not cancel each other out.

tu quoque

Deflecting a criticism by pointing to the same flaw in the critic.

“"You told me to exercise more. But you never go to the gym yourself."”— Example 1 — Easy to spot

Whether the speaker exercises does not change whether the advice is good.

“"You're talking about honesty? You've lied before."”— Example 2 — Easy to spot

Past dishonesty does not make what is being said about honesty wrong.

A government is criticized for its environmental policy. A minister responds: 'The opposition had the same policies for ten years when they were in power.' Is this tu quoque?

Yes. Whether the other party did it too is a separate issue. The current policy still needs to be answered on its own merits. This version is subtle because it sounds like historical context — but it is actually a deflection away from the question.

Burden of Proof

Whoever makes a claim has the job of proving it. This fallacy shifts that job. It says: prove my claim is wrong. But the person making the claim should prove it is right — not the other way around.

burden of proof

The responsibility of the person making a claim to support it with evidence.

“"I believe there is a planet made of diamonds. Prove me wrong."”— Example 1 — Easy to spot

The person making the claim needs to show evidence — not demand others disprove it.

“"This supplement cures headaches. No study has proven it doesn't work."”— Example 2 — Easy to spot

Lack of evidence against something is not proof that it works.

A company says its new product has no side effects. When asked for evidence, they say: 'There have been no reported cases of harm.' Is this a burden of proof issue?

Yes. 'No reported cases' is not the same as 'we tested and found no harm.' It could mean no one has studied it, or that problems went unreported. The company should provide evidence of safety — not point to the absence of reports. This version sounds responsible, which makes it harder to catch.

Appeal to Ignorance

This says something must be true because it has not been proven false. Or it says something must be false because it has not been proven true. Not knowing something is not the same as knowing it.

appeal to ignorance

Claiming something is true because it has not been proven false — or false because not yet proven true.

“"No one has proven ghosts do not exist. So ghosts must exist."”— Example 1 — Easy to spot

Absence of proof is not proof of presence.

“"Scientists have not proven this food is harmful. So it must be safe."”— Example 2 — Easy to spot

The absence of a finding is not proof of safety. The food may simply not have been studied yet.

A researcher says: 'No studies have found a link between this medication and heart disease, so the medication is safe for the heart.' Is this appeal to ignorance?

Yes. No studies finding a link is not the same as studies finding no link. It may mean the connection was never tested. The careful version would be: 'No studies have found a link so far — but more research is needed.' This version is easy to miss because it comes from a researcher and sounds scientific.

False Equivalence

False equivalence compares two things as if they are equal when they are not. The comparison looks balanced. But the two sides are very different in size, evidence, or importance.

false equivalence

Treating two things as equal when they are not.

“"Teaching only one scientific theory is just as biased as teaching only religion."”— Example 1 — Easy to spot

Scientific theories and religious beliefs use different standards of evidence. Comparing them as equally biased ignores that difference.

“"One scientist disagrees with climate change. So the scientific community is divided."”— Example 2 — Easy to spot

One dissenting voice is not equal to thousands of studies. The sizes are not comparable.

A news show gives one vaccine supporter and one vaccine opponent equal airtime, then says: 'We present both sides.' Is this false equivalence?

Yes. Equal time creates the impression of equal support. But if 99% of scientists support the vaccine and 1% oppose it, giving each side equal airtime misrepresents where the evidence stands. This version is very hard to spot — 'both sides' sounds like fairness, which is why it works.