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The Logical Fallacy Spotter

Ten bad arguments, what they sound like, and how to catch one. Ages 9–16.

How to use it: don’t teach all ten. Pick one, name it, and then spot it together for a week — in adverts, in arguments at the table, in what people say online. Naming a thing is what makes it visible. A child who can say “that’s attacking the person’” has turned a vague feeling into an argument.
Attacking the person
ad hominem
“You’re just a kid — you wouldn’t understand.”
The tell: they’re talking about who said it, not what was said.
Everybody’s doing it
bandwagon
“All my friends are allowed. Everyone has one.”
The tell: lots of people believing something isn’t evidence it’s true.
The exaggerated version
straw man
“So you’re saying we should have no rules at all?”
The tell: they answered something you never actually said.
Only two choices
false dilemma
“Either we ban it, or somebody gets hurt.”
The tell: ask whether there’s a third option. There usually is.
One thing leads to disaster
slippery slope
“Stay up late once and you’ll never get up for school again.”
The tell: every step in the chain needs its own proof, not just the first.
A famous person said it
misused authority
“It must be true — a celebrity posted it.”
The tell: ask whether they’re an expert on this exact thing.
If you cared, you’d agree
appeal to emotion
“Think of the children. How can you say no?”
The tell: feeling strongly about something isn’t the same as being right.
Moving the target
moving the goalposts
“Fine, you did that — but now prove this too.”
The tell: the thing you had to prove changed after you proved it.
It happened after, so it caused it
post hoc
“I wore these socks and we won. The socks did it.”
The tell: one thing following another doesn’t mean it caused it.
Well, you did it too
tu quoque
“You can’t tell me off — you did the same thing!”
The tell: even if that’s true, it doesn’t make the first thing okay.
Worth saying out loud: spotting a fallacy doesn’t win the argument. Someone can make a terrible case for a true thing. The point isn’t to catch people out — it’s to notice when a reason isn’t doing the work it’s pretending to do, including your own.
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