How to spot logical fallacies: 8 common ones, with everyday examples

A logical fallacy is a flaw in reasoning: an argument that sounds convincing but doesn’t actually support its conclusion. We all use them, often without noticing, and we’re surrounded by them in ads, headlines and online debates. Learning to spot them doesn’t make you cynical. It makes you a fairer thinker: better at changing your mind for good reasons, and harder to persuade with bad ones.

Here are eight of the most common, with everyday examples.

1. Ad hominem: attacking the person

Example: “Why listen to her opinion on recycling? She drives a car.” The flaw: whether she drives says nothing about whether her argument on recycling is right. Respond to the idea, not the person.

2. Straw man: arguing against a distorted version

Example: “You want fewer cars downtown? So you want to ban everyone from driving.” The flaw: the original claim was more modest. Defeating an exaggerated version proves nothing about the real one.

3. False dilemma: only two options

Example: “Either you work every weekend, or you’re not serious about your career.” The flaw: there are almost always more than two possibilities. Ask: what options are being left out?

4. Bandwagon: everyone’s doing it

Example: “All my friends use this supplement, so it must work.” The flaw: popularity isn’t evidence. Lots of people can believe something that isn’t true.

5. Correlation versus causation

Example: “Since the new café opened, crime on this street went down. Cafés reduce crime.” The flaw: two things happening together doesn’t mean one caused the other. There may be a third factor, such as new street lights, or it may be coincidence.

6. Slippery slope

Example: “If we let students retake one exam, soon nobody will ever study.” The flaw: it assumes a chain of consequences without showing why each step would follow.

7. Appeal to authority, outside their field

Example: “A famous actor says this diet is the healthiest, so it is.” The flaw: expertise in one area doesn’t transfer to another. Expert opinion matters when it’s about their field, and even then, evidence matters more.

8. Hasty generalization

Example: “I had a bad meal at a restaurant in that city; the food there is terrible.” The flaw: one or two cases are too few to support a broad conclusion.

A simple habit for catching them

When an argument feels persuasive, especially one you already agree with, pause and ask three questions:

1. What exactly is the claim? Restate it in your own words.
2. What’s the evidence? Is it actually connected to the claim, or just nearby?
3. What would change my mind? If nothing could, that’s worth noticing.

You won’t catch every fallacy, and you don’t need to. The goal is to slow down just enough to see the shape of an argument before deciding.

Spot is one of Bambú’s three exercise types: a short text with a flaw hidden in it. Find it, read a clear explanation of the pattern, and over time you’ll start seeing these everywhere, which is exactly the point.