Logical Fallacies

Common Errors in Reasoning That Undermine Arguments

Logical fallacies are patterns of reasoning that appear persuasive but are actually flawed. They often exploit emotional reactions, ambiguity, or cognitive shortcuts, leading people to accept conclusions that do not logically follow from the premises.

Why Fallacies Matter

Recognizing fallacies helps you avoid being misled, construct stronger arguments, and engage in more productive debates. Fallacies don’t always mean someone is lying—many are used unintentionally.

Popular Logical Fallacies

Ad Hominem ▼

An argument that attacks the person making a claim rather than the claim itself.

You shouldn’t take her argument about economics seriously—she didn’t even graduate from college.

Straw Man ▼

Misrepresenting an opponent’s argument to make it easier to attack.

He wants to reduce military spending, so clearly he wants the country to be defenseless.

Appeal to Authority ▼

Claiming something is true simply because an authority figure believes it, without proper evidence.

This diet must work because a famous actor says they follow it.

False Dilemma ▼

Presenting only two options when more possibilities exist.

Either you support this policy, or you don’t care about public safety.

Slippery Slope ▼

Assuming that a small first step will inevitably lead to extreme consequences.

If we allow students to redo one test, soon they’ll expect to redo every assignment.

Circular Reasoning ▼

The conclusion is assumed in the premise instead of being supported by evidence.

This law is just because it’s the law.

Hasty Generalization ▼

Drawing a broad conclusion from a small or unrepresentative sample.

I met two rude people from that city, so everyone there must be rude.

Post Hoc Ergo Propter Hoc ▼

Assuming that because one event followed another, it was caused by it.

I wore my lucky shirt and we won the game, so the shirt caused the win.

Red Herring ▼

Introducing an irrelevant topic to divert attention from the original issue.

Why worry about climate change when there are still people without jobs?

Appeal to Emotion ▼

Using emotional manipulation instead of logical reasons to persuade.

If you don’t support this charity, think of how many children will suffer.

Bandwagon ▼

Arguing that something must be true or good because many people believe it.

Millions of people use this app, so it must be the best one available.

False Cause ▼

Assuming a causal relationship without sufficient evidence.

Crime rates increased after the new mayor was elected, so the mayor caused the crime.

Equivocation ▼

Using ambiguous language to mislead or misrepresent the truth.

The sign said 'Fine for parking here,' so it’s okay to park.

Appeal to Ignorance ▼

Claiming something is true because it hasn’t been proven false, or vice versa.

No one has proven aliens don’t exist, so they must be real.

False Analogy ▼

Making a comparison between two things that aren’t truly comparable.

Employees are like nails; just as nails must be hit on the head to work, so must employees be pressured to perform.

Composition ▼

Assuming what is true of the parts is true of the whole.

Each player on the team is excellent, so the team as a whole must be unbeatable.

Division ▼

Assuming what is true of the whole is true of its parts.

The team is the best in the league, so every player must be the best in their position.

Begging the Question ▼

Making a claim that assumes the conclusion is already true.

Reading is beneficial because it’s good for you.

Appeal to Tradition ▼

Claiming something is better or correct simply because it’s traditional or has been done for a long time.

We should keep this policy because it’s always been this way.

Appeal to Novelty ▼

Claiming something is better or correct simply because it is new or modern.

This smartphone must be the best; it just came out.

No True Scotsman ▼

Making an ad hoc change to a generalization to exclude a counterexample.

No true vegetarian would eat meat. Oh, you eat eggs? Then you’re not a true vegetarian.

Tu Quoque ▼

Deflecting criticism by accusing the critic of the same issue.

You say smoking is bad, but you used to smoke, so your argument is invalid.

Loaded Question ▼

Asking a question that contains an assumption that may not be true.

Have you stopped wasting time at work?

Cherry Picking ▼

Selecting only evidence that supports your argument while ignoring contrary evidence.

This study shows the drug works, ignoring all studies showing it doesn’t.

How to Spot Fallacies

Ask whether the conclusion truly follows from the premises
Watch for emotional language replacing evidence
Check if alternative explanations are ignored
Look for attacks on people instead of ideas

The first principle is that you must not fool yourself—and you are the easiest person to fool.

— Richard Feynman

Mastering logical fallacies doesn’t just make you a better debater—it makes you a clearer thinker. By learning to identify these reasoning errors, you strengthen your ability to evaluate claims, challenge misinformation, and form well-supported conclusions.