Nuprl Lemma : triple-neg-ext

[A:ℙ]. uiff(¬¬¬A;¬A)


Proof




Definitions occuring in Statement :  uiff: uiff(P;Q) uall: [x:A]. B[x] prop: not: ¬A
Definitions unfolded in proof :  member: t ∈ T triple-neg
Lemmas referenced :  triple-neg
Rules used in proof :  introduction sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity cut instantiate extract_by_obid hypothesis sqequalRule thin sqequalHypSubstitution equalityTransitivity equalitySymmetry

Latex:
\mforall{}[A:\mBbbP{}].  uiff(\mneg{}\mneg{}\mneg{}A;\mneg{}A)



Date html generated: 2018_05_21-PM-00_00_24
Last ObjectModification: 2018_05_19-AM-07_14_04

Theory : core_2


Home Index