eolas/neuron/cd6bdaba-031a-4daf-adf2-ef3b075243e6/Negation_Introduction.md

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.