---
categories:
  - Logic
tags: []
---

# Negation Elimination

Like the [introduction](/Logic/Proofs/Negation_Introduction.md) rule for negation, the elimination rule also works by deriving a contradiction. It is basically _Negation Introduction_ in reverse. Instead of starting the sub-proof with a true proposition from which you derive a contradiction, you start with the negation of a proposition, derive a contradiction and then assert the positive of the negated proposition you started out with.

![](/_img/negate-elim.png)
