Logical Fallacies

Understanding logical fallacies is essential for clear thinking and effective argumentation. Below are 20 common logical fallacies with explanations and examples.

Ad Hominem

Attack the person.

It’s one of the oldest tricks in the book: Attempt to discredit the messenger so you don’t have to face the message. Rather than engaging with the substance of an argument, the person attacks the character, circumstances, or personal attributes of the individual making the claim. This fallacy is a diversionary tactic that shifts focus from the argument’s merits to the arguer’s perceived flaws. The truth or falsehood of a claim stands independent of who voices it.

Example: “She argues for climate policy reform, but she flies on private jets. We can’t take her seriously.”

An all-too-common “strategy” in political discourse and social media debates.

The Straw Man

Distort to destroy.

The person distorts your argument into a weaker version so they can easily tear it down. Instead of engaging with your actual point, they invent a flimsy one and proudly defeat it. This fallacy involves misrepresenting someone’s position to make it easier to attack. The arguer constructs a caricature of the original argument, defeats this weaker version, then claims victory over the actual position. It’s intellectual dishonesty disguised as debate.

Example: “You support healthcare reform? So you want the government to control every aspect of our lives?”

A classic move for anyone more interested in winning than understanding.

False Dilemma

You only have two choices.

They present two extreme options as if they’re the only possibilities. Oversimplification to avoid confronting the fact that reality is almost always in some shade of grey. Also known as the “either/or” fallacy, this artificially limits the options available, forcing a choice between two extremes while ignoring the spectrum of possibilities that exist between them. It’s a favorite tool of those seeking to polarize rather than illuminate.

Example: “Either we cut all social programs, or the economy will collapse completely.”

This thrives in political and social media echo chambers where nuance goes to die.

Appeal to Authority

Trust me, they said so.

The person uses an expert’s opinion as proof, without any supporting evidence. Experts can inform your thinking, but they generally shouldn’t replace it. This fallacy occurs when someone argues that a claim must be true simply because an authority figure says so, without presenting the actual reasoning or evidence. While expert opinion can be valuable, it becomes fallacious when used as a substitute for actual argument, especially when the authority is outside their domain of expertise or when experts disagree.

Gibson’s Law is a tongue-in-cheek observation that, “For every PhD, there’s an equal and opposite PhD.” In simple terms, you can find an expert on both sides of any given argument, so we cannot default to using them as proof.

Example: “A famous actor says this supplement cured their illness, so it must work for everyone.”

People often hide behind credentials when logic runs out.

Bandwagon Fallacy

Everyone’s doing it.

Assuming something is true simply because everyone believes it. Popularity isn’t evidence. The crowd has been confidently wrong many times before. This fallacy appeals to the desire to conform and belong, suggesting that widespread acceptance makes something correct. History is littered with examples of popular beliefs that were entirely wrong, from geocentrism to bloodletting. Mass agreement is a social phenomenon, not a logical proof.

Example: “Every major company is implementing this management strategy, so it must be the best approach.”

The herd may be loudest right before walking off the cliff.

Sunk Cost Fallacy

Can’t quit now.

The person argues to continue on the path simply because of what has already been invested to date. In truth, past effort has no bearing on whether continuing makes sense. This fallacy causes people to irrationally continue investing in failing ventures because they’ve already committed resources. The past investment (time, money, effort) is gone regardless of future decisions. Rational decision-making should be based solely on future costs and benefits, not on mourning sunk costs.

Example: “I’ve already sat through 90 minutes of this terrible movie. I might as well watch the ending.”

Smart people cut losses when they no longer make sense. Fools double down to avoid accepting the loss.

Red Herring

Hey, look over there!

Hunting dog trainers would often use a kippered herring as a distracting scent to test whether the dogs were able to stay on track.

The red herring is a distraction masquerading as relevant. Someone shifts the topic to something tangential to avoid addressing the issue at hand. This fallacy introduces irrelevant material to divert attention from the original argument. The new topic might be emotionally charged or interesting, but it doesn’t address the actual point being debated. It’s a sleight-of-hand that substitutes spectacle for substance.

Example: “Why should we discuss the budget deficit? We need to talk about the rise of social media addiction among teenagers.”

A masterclass in misdirection.

Tu Quoque

“And you too.”

Instead of addressing a criticism, the person points out your flaws to avoid accountability. This fallacy, Latin for “you also,” attempts to deflect criticism by accusing the critic of hypocrisy. Even if the accusation of hypocrisy is true, it doesn’t address the validity of the original criticism. A hypocrite can still make a valid point. This is a special type of ad hominem that’s particularly common in defensive arguments.

Example: “You criticize my spending habits? You just bought a luxury watch last month.”

Alleged hypocrisy doesn’t invalidate truth.

Hasty Generalization

Small sample, big claim.

Someone draws a sweeping conclusion from very limited evidence. Anecdotes are not data. One case does not make a real pattern. This fallacy involves extrapolating from insufficient data to reach broad conclusions. Our brains are wired for pattern recognition, which makes us susceptible to seeing trends where none exist. Statistical significance requires adequate sample sizes and proper methodology, not cherry-picked personal experiences.

Example: “I met two rude people from that city, so everyone there must be unfriendly.”

Humans love shortcuts, but sound logic requires a larger sample size.

The Fallacy Fallacy

Bad argument ≠ bad idea.

The person assumes a claim is false simply because it was argued poorly. Bad reasoning doesn’t automatically make an idea wrong, just unproven. Also known as “the argument from fallacy,” this meta-fallacy concludes that if an argument contains a logical error, its conclusion must be false. In reality, a conclusion can be true even if the reasoning used to support it is flawed. A bad map doesn’t mean the destination doesn’t exist.

Example: “You used a straw man argument to defend renewable energy, therefore renewable energy doesn’t work.”

Don’t confuse a poor advocate with a poor idea.

The Texas Sharpshooter

Cherry-pick the data.

A marksman fires bullets at a wall, then paints a target around the tightest cluster of bullet holes. The person chooses the story first, then pulls the evidence to confirm it. This fallacy involves selecting data that supports your conclusion while ignoring data that contradicts it. It’s a form of confirmation bias where you retrofit a pattern to random data, creating the illusion of causation or significance where none exists. The data is manipulated after the fact to appear meaningful.

Example: “Our strategy works perfectly—just look at these five success stories from our portfolio of 200 companies.”

Avoid the conflicting evidence by only choosing the good.

Post Hoc Ergo Propter Hoc

False cause.

A Latin phrase meaning, “After this, therefore because of this.” The person assumes that just because B followed A, A must have caused B. This fallacy confuses temporal sequence with causal relationship. Just because two events occur in sequence doesn’t mean the first caused the second. Coincidence, third variables, and reverse causation are all possibilities that this fallacy ignores. It’s the foundation of superstition and flawed causal reasoning.

Example: “The new CEO took over in January and profits increased in March. The CEO’s leadership clearly caused the profit increase.”

Correlation doesn’t equal causation.

Slippery Slope

The domino effect.

Someone insists that one small step will inevitably lead to a catastrophe. Each individual step may sound plausible, but the chain connecting them rarely holds up. This fallacy argues that a relatively minor action will trigger a chain reaction leading to an extreme outcome, without providing evidence for why each step in the chain is inevitable. It relies on fear and extrapolation rather than demonstrated causation. While some slopes are indeed slippery, this fallacy assumes they all are.

Example: “If we allow employees to work from home one day a week, soon they’ll demand full remote work, then they’ll stop working altogether, and the company will collapse.”

Think of this like a parlay bet (a bet that links together multiple bets or events into one). The more bets linked together, the lower the odds of the parlay hitting (and the higher the payout).

Any one of the events may have a reasonable probability of occurring, but all of them occurring, and in the correct order, is often nearly impossible.

Burden of Proof

Ok, then prove me wrong.

The person claims something is true simply because it can’t be proven false. In truth, the responsibility to prove the claim lies with the person making it. This fallacy shifts the burden of proof from the claimant to the skeptic. In rational discourse, whoever makes a positive claim bears the responsibility of providing evidence for it. Demanding others disprove your unsupported assertion is intellectually backwards and would make any wild claim defensible.

Example: “There’s an invisible dragon in my garage. You can’t prove there isn’t, so I’m right.”

The absence of evidence to the contrary isn’t evidence in support.

Personal Incredulity

I don’t get it, so it’s wrong.

The person rejects the idea because they can’t understand or imagine how it could be true. A personal lack of understanding doesn’t make something impossible. This fallacy mistakes individual comprehension for objective reality. Our inability to grasp complex concepts or counterintuitive truths doesn’t render them false. Quantum mechanics, relativity, and countless other verified phenomena defy common intuition yet remain true. Humility requires acknowledging the limits of our imagination.

Example: “I can’t understand how evolution could create something as complex as the human eye, therefore it must be false.”

Complex ideas often look absurd before they’re real. Real innovation is everyone agreeing with you, later.

Loaded Question

The trap question.

Someone raises a Trojan Horse question that smuggles in an accusation or assumption. The question is pre-loaded with a presumption of guilt. No matter how you answer, you lose. This fallacy embeds an unproven assumption within a question, forcing the respondent to either accept the false premise or appear evasive. It’s linguistic entrapment that treats controversial assumptions as established facts. The proper response is to reject the question’s premise entirely.

Example: “How long have you been embezzling funds from the company?”

A classic rigged game used by prosecutors, politicians in debates, and bad-faith interviewers.

No True Scotsman

Moving the goalposts.

The person redefines a group to protect their claim from counterexamples. They shift the rules mid-argument to stay in the right. This fallacy protects a universal claim from refutation by retroactively modifying the definition to exclude counterexamples. When faced with contradictory evidence, instead of revising the claim, the arguer changes what qualifies as a valid member of the group. It’s circular reasoning wrapped in definitional manipulation.

Example:

“No successful entrepreneur gives up easily.”

“What about Sarah? She’s successful and she walked away from three ventures.”

“Well, she’s not a true entrepreneur then.”

Rather than acknowledge the counter-argument and evidence, the terms of the argument are changed to simply exclude the counter-argument.

Equivocation

Word games.

The same word is used in two different ways to mislead the opponent. It sounds consistent on the surface, but the meaning quietly shifts. This fallacy exploits the multiple meanings of a word or phrase, using one definition in the premise and another in the conclusion. It creates a false appearance of logical coherence through semantic sleight of hand. Language precision is essential to avoid this trap.

Example: “The law requires us to treat all citizens equally. Therefore, we should give everyone the exact same income regardless of their work.”

Imprecise language leads to imprecise argument.

Non-Sequitur

That doesn’t follow.

The conclusion doesn’t logically follow from the premise. It’s random reasoning masquerading as thoughtful insight. Latin for “it does not follow,” this fallacy presents a conclusion that has no logical connection to the premises offered. The leap from evidence to conclusion crosses a chasm of missing logic. While all fallacies involve faulty reasoning, non-sequitur is the catch-all for conclusions that simply don’t follow from their stated support.

Example: “Our competitor launched a new product last month. We should clearly redesign our office space.”

Beware the conclusion out of thin air.

Begging the Question

Circular reasoning.

The person creates a circular argument where the conclusion they seek is assumed in the premise itself. It vaguely sounds like logic, but it collapses on itself. Also called “circular reasoning,” this fallacy occurs when an argument’s premise assumes the truth of the conclusion instead of supporting it. It’s a closed loop that provides no actual evidence, just restatement. The argument goes nowhere because it starts where it claims to end.

Example: “This book is divinely inspired because it says so in the book itself, and divine texts don’t lie.”

A logical dog chasing its own tail.

Source

This page was inspired by this article by Sahil Bloom: The Logical Fallacy Field Guide