Critical Thinking Cheat Sheet: Lesson 3 - Spotting Logical Fallacies
Common Logical Fallacies
Fallacy | Description | Example | How to Respond |
Ad Hominem | Attacking the person instead of their argument | “You can’t trust Dr. Smith’s research because she drives an SUV.” | “Let’s focus on the evidence and reasoning, not who’s making the argument.” |
Appeal to Authority | Claiming something is true because an authority says so | “This investment must be sound because Warren Buffett recommends it.” | “What specific evidence supports this view, beyond who believes it?” |
False Dilemma | Presenting only two options when more exist | “Either we cut regulations, or we’ll lose jobs.” | “Are those really the only two options? What about approaches that do both?” |
Slippery Slope | Claiming one step will lead to extreme consequences | “If we ban assault weapons, soon all guns will be illegal.” | “What evidence suggests this specific change would lead to those outcomes?” |
Straw Man | Misrepresenting an opponent’s argument | “You want public transportation? So you want to force everyone to give up their cars?” | “That’s not what I’m saying. My actual position is…” |
Appeal to Popularity | Suggesting something is true because it’s widely believed | “Most people eat fast food regularly, so it can’t be unhealthy.” | “Let’s look at the evidence, not just how many people believe it.” |
Post Hoc Ergo Propter Hoc | Assuming that because B followed A, A caused B | “I wore my lucky socks and we won, so my socks helped us win.” | “What evidence suggests a causal relationship rather than coincidence?” |
Appeal to Emotion | Using emotional language instead of logical arguments | “Think of the children! How could anyone oppose this policy?” | “I share your concern, but let’s evaluate whether this approach would be effective.” |
Red Herring | Introducing an irrelevant topic to distract | “We’re discussing potholes.” “What about crime rates?” | “That’s a separate issue we could discuss later. Can we resolve the original topic first?” |
Hasty Generalization | Drawing broad conclusions from limited evidence | “My neighbor tried that diet and got sick, so it must be dangerous.” | “Is that single experience enough to draw a general conclusion?” |
Circular Reasoning | Using the conclusion as a premise | “The Bible is the word of God because it says so in the Bible.” | “Can you provide evidence that doesn’t already assume the conclusion?” |
Fallacies in Different Contexts
Politics: - False dilemmas (“Either you support policy X, or you don’t care about group Y”) - Straw man arguments (“My opponents want to completely eliminate [program]”) - Ad hominem attacks (focusing on personal life rather than policies)
Media: - Appeal to emotion (using fear or outrage rather than evidence) - Cherry-picking statistics to support a narrative - False equivalence between positions of unequal evidence
Advertising: - Appeal to popularity (“Everyone is buying this product”) - Post hoc reasoning (“Use this product and you’ll be successful like these people”) - Appeal to false authority (celebrities endorsing products outside their expertise)
Self-Monitoring for Fallacies
- Check your own arguments for fallacies before presenting them
- Be willing to acknowledge when you’ve used fallacious reasoning
- Practice reformulating fallacious arguments into stronger, logical ones
- Notice when emotional reactions might be leading you toward fallacious thinking
Remember
Identifying fallacies isn’t about “winning” arguments but promoting clearer thinking and more productive conversations about important issues.