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Part of the series on
Logic and rhetoric
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General logic
Bad logic

Presupposition is not directly related to Presuppositionalism, which is a religious belief, although presuppositionalist beliefs are certainly full of presupposition.

A presupposition is a linguistic term for an implicit assumption in a phrase, usually a claim or a question.

Presuppositions can be used in a fallacious manner by playing on these assumptions, e.g., by asking a loaded yes-or-no question that will implicate the speaker in something disagreeable no matter which way he answers.

The appropriate answer to a question based upon a false presupposition is "mu."[1]


  • Phrase: "Have you stopped beating your wife?"
  • Presupposition: 1) You, at some point, have at least one wife. 2) At some point you have beaten your wife (regardless whether that is the same wife as the first presupposition).
  • Phrase: "I have quit smoking."
  • Presupposition: I used to smoke.

And from Alice in Wonderland by Lewis Carroll:

“How am I to get in?” asked Alice again, in a louder tone.

“Are you to get in at all?” said the Footman. “That’s the first question, you know.”

No relation to[edit]

See also[edit]


  1. See mu (negative)Wikipedia's W.svg at Wikipedia.