There is no RationalWiki without you. We are a small non-profit with no staff – we are hundreds of volunteers who document pseudoscience and crankery around the world every day. We will never allow ads because we must remain independent. We cannot rely on big donors with corresponding big agendas. We are not the largest website around, but we believe we play an important role in defending truth and objectivity.
If everyone who saw this today donated $5, we would meet our goal for 2019.
| Fighting pseudoscience isn't free.|
We are 100% user-supported! Help and donate $5, $20 or whatever you can today with !
| Part of the series on|
Logic and rhetoric
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."
- 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
- See mu (negative) at Wikipedia.