paste an argument.
see where it slips.

fallacy field guide

The eight patterns every line is checked for. Definitions and examples are written by hand. Only the percentages come from the model.

• ad hominem

  attacks the person

  Goes after the person making the argument instead of the argument itself. Their character, motives, looks or past get treated as if they settle whether the claim is true.

  "You can't trust her budget plan. She can't even keep her own car clean."

  A messy car says nothing about whether the numbers in the plan add up.

• strawman

  distorts the other view

  Restates the other side as a weaker, cruder or more extreme version of what they said, then knocks that version down. The real position never gets answered.

  "He wants fewer cars downtown. So he wants to ban everyone from driving to work."

  Fewer cars and a total ban are very different proposals. Only the second one is easy to mock.

• false dilemma

  only two options

  Presents a choice as if there were only two possibilities when there are clearly more. Usually one option is made to look terrible so the other wins by default.

  "Either we cut the arts program or the school goes bankrupt."

  Budgets have many levers. Framing it as one cut or ruin hides all of them.

• slippery slope

  one step leads to doom

  Claims that a small first step will set off a chain of events ending somewhere extreme, without showing why each link in the chain would actually happen.

  "If we let students retake one exam, soon nobody will study for anything."

  Each step needs its own reason. One retake policy does not explain the collapse of studying.

• appeal to authority

  status as proof

  Treats who said something as proof that it is true, especially when the person is famous or senior but not an expert in the topic at hand.

  "A famous actor swears by this diet, so it must work."

  Acting skill is not nutrition research. Fame is standing in for evidence.

• whataboutism

  deflects to someone else

  Answers a criticism by pointing at somebody else's wrongdoing instead of responding to it. The original point is left standing but the conversation moves on.

  "Sure, our factory leaks, but what about the plant across the river?"

  The other plant being bad does not make this leak any cleaner.

• hasty generalization

  too few cases

  Draws a sweeping conclusion from a handful of cases, a personal anecdote or an unrepresentative sample.

  "My two cousins hated living there, so it's an awful city."

  Two people are not a city of a million. The sample is far too small to carry the claim.

• circular reasoning

  assumes its conclusion

  Uses the conclusion as one of its own premises, so the argument goes in a loop. It sounds like a reason but only restates the claim.

  "This news source is trustworthy because it reports the truth."

  Whether it reports the truth is exactly the question. The reason and the claim are the same thing.