eolas/Logic/Proofs/Negation_Introduction.md

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categories:
  - Logic
tags: []
---

# Negation Introduction

This is also known as _proof by contradiction_. You start with an assumption declared in a sub-proof. If you can derive a contradiction from this assumption (typically from the introduction of another proposition and its negation), then you are permitted to derive the negation of the auxiliary assumption in the main proof.

![](/_img/negate-intro.png)
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Initial commit, pure MD 2022-04-23 13:26:53 +01:00			`---`

Autosave: 2022-12-25 16:00:05 2022-12-25 16:00:05 +00:00			`# Negation Introduction`
Initial commit, pure MD 2022-04-23 13:26:53 +01:00
Autosave: 2022-12-25 16:00:05 2022-12-25 16:00:05 +00:00			`This is also known as _proof by contradiction_. You start with an assumption declared in a sub-proof. If you can derive a contradiction from this assumption (typically from the introduction of another proposition and its negation), then you are permitted to derive the negation of the auxiliary assumption in the main proof.`

Create script to rename image URLs and apply 2022-12-29 20:22:34 +00:00			`![](/_img/negate-intro.png)`