# Circular reasoning

*Also called: Begging the question, petitio principii*

- **Cluster:** Broken structure — The form itself does not carry the conclusion
- **Page:** https://fallacy.wiki/fallacy/circular/
- **In Arabic:** https://fallacy.wiki/ar/fallacy/circular.md
- **Licence:** CC BY 4.0 — https://creativecommons.org/licenses/by/4.0/

## What it is

Assuming in the premises the very thing the argument is supposed to establish.

## In the wild

> The rules are correct because the rulebook says so.

## How to answer it

Ask for a reason that does not already presuppose the conclusion.

## Origin and naming

Aristotle discussed it in the Topics and Prior Analytics as τὸ ἐξ ἀρχῆς αἰτεῖν — 'asking for the initial thing' — a fault in formal debate where one side requests the very thesis at issue. Latin translators rendered it petitio principii, and sixteenth-century English gave us 'begging the question'.

## More places it shows up

- This framework is the industry standard because it's the one the industry uses.
- The new policy is fair because it treats everything in line with the policy.
- You can trust the report — it was approved by the team that wrote it.
- This diet works because it produces weight loss, and we know it produces weight loss because it works.

## How to spot it

- Notice when stripping the wording down leaves the premise and the conclusion saying the same sentence twice.
- Notice when the proof works only for people who already agree with the conclusion.
- Notice when asking 'and why is the premise true?' sends you straight back to the conclusion.

## Nearby

- [Definist fallacy](https://fallacy.wiki/fallacy/definist.md)
- [Package deal fallacy](https://fallacy.wiki/fallacy/package-deal.md)

## Read more

- [Wikipedia](https://en.wikipedia.org/wiki/Begging_the_question)
- [1911 Encyclopædia Britannica (Petitio Principii)](https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Petitio_Principii)

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From fallacy.wiki — a bilingual field guide to 91 logical fallacies, published by phi holdings. Licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/): reuse freely with attribution to fallacy.wiki.