Category:Double Negation Introduction

From ProofWiki
Jump to navigation Jump to search

This category contains pages concerning Double Negation Introduction:


The rule of double negation introduction is a valid argument in types of logic dealing with negation $\neg$.

This includes propositional logic and predicate logic, and in particular natural deduction.


Proof Rule

If we can conclude $\phi$, then we may infer $\neg \neg \phi$.


Sequent Form

$p \vdash \neg \neg p$