17 lines
529 B
Markdown
17 lines
529 B
Markdown
|
---
|
||
|
|
tags:
|
||
|
|
- logic
|
||
|
|
- propositional-logic
|
||
|
|
---
|
||
|
|
|
||
|
|
# Negation Elimination
|
||
|
|
|
||
|
|
Like the [introduction](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.
|
||
|
|
|
||
|
|
|