eolas/neuron/9445c5fd-135c-4b0b-a70c-7a6fd45d9d58/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.