Full Idea
Double Negation Elimination is a rule of inference which the classicist accepts without restriction, but which the intuitionist accepts only for decidable propositions.
Gist of Idea
Intuitionists can accept Double Negation Elimination for decidable propositions
Source
Ian Rumfitt (The Boundary Stones of Thought [2015], 1.1)
Book Reference
Rumfitt,Ian: 'The Boundary Stones of Thought' [OUP 2015], p.3
A Reaction
This cures me of my simplistic understanding that intuitionists just reject the rules about double negation.