Fallacy guide
A short reference for the logical and rhetorical fallacies Jiddu can detect.
Relevance
Ad hominem
Attacks the person making the argument rather than the argument itself.
Example“You can't trust her economic analysis — she's never even had a real job.”
Straw man
Misrepresents an opponent's position to make it easier to attack.
Example“So you're saying we should abolish all borders and let anyone in?” (when the proposal was only a visa reform).
Red herring
Diverts attention from the issue with an irrelevant topic.
Example“Why worry about climate change when we still have unemployment?”
Tu quoque
Rejects criticism by pointing to similar behavior by the critic.
Example“You can't tell me to quit smoking — you used to smoke too.”
Genetic fallacy
Judges a claim by its origin rather than its content.
Example“That study is from a tobacco-funded lab, so it's worthless.” (without engaging with the data).
Non sequitur
The conclusion does not follow from the premises.
Example“She runs marathons, so she'd make a great manager.”
Whataboutism
Deflects an accusation by pointing at someone else's wrongdoing instead of addressing it.
Example“Our party misused funds? What about the opposition's scandals?”
Poisoning the well
Discredits a source in advance so that anything it says gets dismissed.
Example“Before my opponent speaks, remember he's a paid lobbyist.”
Guilt by association
Rejects a claim because of who else holds it or is linked to it.
Example“That policy was also favored by dictators, so it must be wrong.”
Thought-terminating cliché
Uses a stock phrase to shut down discussion instead of engaging with the argument.
Example“It is what it is — no point discussing it.”
Presumption
Appeal to nature
Argues something is good because it is natural (or bad because unnatural).
Example“This remedy is natural, so it's safer than any drug.”
False dichotomy
Presents only two options when more exist.
Example“Either you're with us or you're against us.”
Circular reasoning
The conclusion is included in the premise (begging the question).
Example“This translation is accurate because it says exactly what the original says.”
Loaded question
Phrases a question to presuppose an unproven claim.
Example“Have you stopped lying to your team?”
Moving the goalposts
Demands more evidence after the original demand was met.
ExampleAfter being shown peer-reviewed studies: “Yeah, but who funded them?”
Burden of proof shifting
Demands the opponent disprove the claim instead of proving it.
Example“Prove ghosts don't exist.”
Sunk cost fallacy
Argues to continue a course of action because of what was already invested in it.
Example“We've spent two years on this project; we can't stop now.”
Moralistic fallacy
Concludes something cannot be true because it would be morally wrong.
Example“People can't be born with violent tendencies — that would be unjust.”
Affirming the consequent
From “if A then B” and “B”, wrongly concludes “A”.
Example“Great products sell well; this sold well, so it must be great.”
Denying the antecedent
From “if A then B” and “not A”, wrongly concludes “not B”.
Example“If you study, you'll pass. You didn't study, so you'll fail.”
Causal reasoning
Slippery slope
Asserts that one small step leads inevitably to extreme consequences without justification.
Example“If we let students retake one exam, soon they'll demand to retake everything.”
Post hoc ergo propter hoc
Assumes that because B followed A, A caused B.
Example“I wore my lucky socks and we won — they bring victory.”
Correlation ≠ causation
Treats a correlation as proof of causation.
Example“Ice cream sales correlate with drownings, so ice cream causes drowning.”
Gambler's fallacy
Expects independent random events to “balance out” past outcomes.
Example“Red has come up five times in a row — black is due next.”
Scapegoating
Blames a complex problem on a single person or group.
Example“Housing is unaffordable because of immigrants.”
Evidence
Appeal to authority
Uses an authority's opinion as evidence when the authority is irrelevant or biased.
Example“A Nobel laureate in physics says this diet works, so it must.”
Appeal to popularity (ad populum)
Claims something is true because many people believe it.
Example“Millions of people use this app, so it must be the best.”
Appeal to tradition
Argues something is correct because it has been done that way.
Example“We've always done it this way; there's no reason to change.”
Hasty generalization
Draws a broad conclusion from a small or biased sample.
Example“I met two rude tourists from there — people from that country are rude.”
Anecdotal evidence
Uses a personal experience or isolated example as if it were conclusive.
Example“My grandfather smoked his whole life and lived to 95, so smoking isn't that bad.”
Cherry picking
Highlights only data that supports the claim, ignoring contradicting evidence.
ExampleQuoting the one quarter when revenue grew, ignoring the four it shrank.
Appeal to ignorance
Claims something is true because it has not been proven false (or vice versa).
Example“No one has proven aliens don't visit Earth, so they must.”
Appeal to novelty
Claims something is better simply because it is newer.
Example“This framework just launched — it's obviously superior to the old stack.”
Survivorship bias
Draws conclusions only from the cases that made it through a selection, ignoring the failures.
Example“College dropouts like Jobs and Gates got rich — dropping out works.”
Base rate neglect
Judges probability from a vivid detail while ignoring how rare the event is overall.
Example“The test is 99% accurate and came back positive, so you almost certainly have it.” (for a one-in-a-million disease).
Ambiguity
No true Scotsman
Redefines a category ad hoc to exclude counterexamples.
Example“No real engineer would skip code review.” “But Alice did.” “Then she's not a real engineer.”
Equivocation
Uses a key term in two different senses within the same argument.
Example“The law of gravity is just a theory, like the theory that the Earth is flat.”
False equivalence
Treats two things as comparable when they differ in important ways.
Example“Saying mean things online is just like physical assault.”
Fallacy of composition
Assumes what is true of the parts must be true of the whole.
Example“Every player on the team is great, so the team must be great.”
Fallacy of division
Assumes what is true of the whole must be true of each part.
Example“That company is innovative, so every employee there is innovative.”
Emotional appeals
Appeal to emotion
Manipulates emotions in place of reasoned argument.
Example“Think of the children who will suffer if this law passes!” (without showing it would actually harm them).
Appeal to fear
Uses fear to drive acceptance of a claim.
Example“If we don't ban this, society will collapse within a year.”
Bandwagon
Argues that one should adopt a position because it is gaining popularity.
Example“Everyone is moving to this framework — we should too.”
Appeal to consequences
Argues a claim is true or false based on whether its consequences are desirable.
Example“Climate change can't be real — fixing it would wreck the economy.”
Appeal to pity
Substitutes compassion for evidence that the claim is true.
Example“I deserve the promotion — I've been through so much this year.”
Appeal to ridicule
Mocks a position instead of refuting it.
Example“Evolution? So your grandfather was a monkey — sure.”
Fallacy selection informed by The Fallacy Guide — all descriptions and examples are Jiddu's own.