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The Fallacy
Field Guide
35 logical fallacies. Named, explained, and illustrated with real-world examples.
A two-sided reference card covering every major formal and informal fallacy — from Affirming the Consequent to Weak Analogy. Each entry includes the structure, a plain-language example, and a one-line explanation of why it fails.
Pin it up. Keep it next to your monitor. Pull it out the next time someone tries to win an argument with an appeal to tradition in a planning meeting.
Get the free PDF ↓Affirming the Consequent
P → Q, Q ∴ P
"If the build passed, the tests ran. The tests ran. Therefore, the build passed."
Straw Man
"So you're saying we should just let anyone push to production without review?"
False Dilemma
"We either ship by Friday or we cancel the whole project."
What's on the card
Side A — Formal Fallacies
Invalid argument forms that mimic valid ones. Each entry shows the logical structure, the valid rule it imitates, a real-world example, and why the inference breaks down.
- Affirming the Consequent
- Denying the Antecedent
- Undistributed Middle
- Illicit Major / Illicit Minor
- Existential Fallacy
Side B — Informal Fallacies
Arguments that fail through psychology, hidden assumptions, or slippery language. Organized into three groups: relevance, presumption, and ambiguity.
- Ad Hominem, Straw Man, Red Herring
- False Dilemma, Slippery Slope, Begging the Question
- Equivocation, Composition, Division
- Appeal to Authority, Bandwagon, Sunk Cost
- …and 18 more
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