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Check My Logic
Check My Logic

Check My Logic

If someone sent you this link, they have concerns.

A plain-language reference to the ways reasoning goes wrong: formal fallacies, informal fallacies and cognitive biases. Each entry gives you enough to understand it at a glance, plus the details, the evidence and the cases where it isn’t an error at all.

3 entries and 2 concepts so far · Show me a random one

Categories

Formal fallacies

An argument whose shape can’t guarantee its conclusion, whatever the argument is about.

Informal fallacies

An argument that fails because of its content or context, not its logical shape.

Cognitive biases

A predictable way human judgment drifts from what the evidence or logic supports.

Every entry

Ad hominem
Rejecting an argument by attacking the person who made it instead of their reasons.
Affirming the consequent
Concluding that the “if” part is true because the “then” part turned out to be true.
Halo effect
Letting one overall impression of someone color your judgment of their unrelated traits.

Underlying ideas

Not errors themselves: the valid forms errors imitate, and the principles that explain them.

Modus ponens
“If P, then Q. P. Therefore Q.” The basic valid way to reason from an if-then statement.
What you see is all there is
Judging from the information in front of you as if it were all the information there is.