Nuprl Lemma : not-not-excluded-middle

P:ℙ(¬¬(P ∨ P)))


Proof




Definitions occuring in Statement :  prop: all: x:A. B[x] not: ¬A or: P ∨ Q
Definitions unfolded in proof :  all: x:A. B[x] not: ¬A implies:  Q false: False uall: [x:A]. B[x] member: t ∈ T uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a prop:
Lemmas referenced :  not_over_or not_wf or_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation cut thin lemma_by_obid sqequalHypSubstitution isectElimination hypothesisEquality hypothesis productElimination independent_isectElimination independent_functionElimination voidElimination because_Cache universeEquality

Latex:
\mforall{}P:\mBbbP{}.  (\mneg{}\mneg{}(P  \mvee{}  (\mneg{}P)))



Date html generated: 2016_05_13-PM-03_46_02
Last ObjectModification: 2015_12_26-AM-09_58_45

Theory : call!by!value_2


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