What Is a Logical Fallacy?
A logical fallacy is an error in reasoning that makes an argument invalid — even if its conclusion might happen to be true. Fallacies are often persuasive precisely because they sound reasonable on the surface. Politicians, advertisers, and pundits rely on them constantly. Learning to recognise them is an essential critical thinking skill.
Here are ten of the most common, with examples you'll recognise.
1. Ad Hominem (Attack the Person)
Instead of addressing an argument, the speaker attacks the character or personal traits of the person making it.
Example: "You can't trust her opinion on climate policy — she drives an SUV."
Even if true, a person's lifestyle doesn't automatically invalidate their argument. Address the claim, not the claimant.
2. Straw Man
Misrepresenting someone's position to make it easier to attack — arguing against a distorted version of what they actually said.
Example: Person A: "We should have stricter gun background checks." Person B: "So you want to confiscate everyone's guns?"
3. False Dichotomy (Either/Or Fallacy)
Presenting only two options when more exist, forcing a choice between two extremes.
Example: "You're either with us or against us."
Reality almost always contains a spectrum of positions. Watch for binary framing in political and media rhetoric.
4. Slippery Slope
Claiming that one event will inevitably lead to a chain of extreme consequences without evidence for that chain.
Example: "If we allow same-sex marriage, next people will want to marry their pets."
5. Appeal to Authority
Using the endorsement of an authority figure as evidence for a claim — even when that authority isn't an expert in the relevant field.
Example: "This celebrity doctor says this supplement cures arthritis, so it must work."
Authority matters — but only within relevant domains, and it's not a substitute for evidence.
6. Hasty Generalisation
Drawing a broad conclusion from a small or unrepresentative sample.
Example: "I've met three rude people from that city — they're all unfriendly."
7. Appeal to Nature
Assuming that something is good because it's "natural" or bad because it's "artificial."
Example: "This remedy is completely natural, so it's safe."
Many natural things are harmful; many synthetic things are beneficial. Natural ≠ good.
8. Circular Reasoning (Begging the Question)
The conclusion is used as a premise — the argument assumes what it's trying to prove.
Example: "The Bible is true because it says so in the Bible."
9. Bandwagon (Appeal to Popularity)
Arguing that something is true or correct because many people believe it.
Example: "Millions of people can't be wrong!"
History is full of widely-held beliefs that turned out to be false. Popularity is not proof.
10. Red Herring
Introducing an irrelevant topic to divert attention from the original issue.
Example: During a debate about healthcare costs: "But what about all those politicians abusing their expense accounts?"
A Quick Reference Table
| Fallacy | Core Error |
|---|---|
| Ad Hominem | Attacking the person, not the argument |
| Straw Man | Distorting the opponent's position |
| False Dichotomy | Ignoring middle-ground options |
| Slippery Slope | Assuming unfounded chain reactions |
| Appeal to Authority | Using status instead of evidence |
| Hasty Generalisation | Over-broad conclusions from thin data |
| Appeal to Nature | Natural = good, artificial = bad |
| Circular Reasoning | Conclusion used as its own premise |
| Bandwagon | Popularity confused with truth |
| Red Herring | Introducing irrelevant distraction |
How to Respond to Fallacies
When you spot a fallacy in conversation, avoid saying "that's a fallacy!" — it tends to put people on the defensive. Instead, gently redirect: "That's interesting, but does it actually address the original question?" The goal is better reasoning, not winning points.