16 lines
430 B
Markdown
16 lines
430 B
Markdown
|
---
|
||
|
|
tags:
|
||
|
|
- logic
|
||
|
|
- propositional-logic
|
||
|
|
---
|
||
|
|
|
||
|
|
# 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.
|
||
|
|
|
||
|
|
|