Nuprl Lemma : decidable__not

∀[P:ℙ]. (Dec(P) ⇒ Dec(¬P))


Proof




Definitions occuring in Statement :  decidable: Dec(P),  uall: ∀[x:A]. B[x],  prop: ℙ,  not: ¬A,  implies: P ⇒ Q
Definitions unfolded in proof :  not: ¬A,  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ
Lemmas referenced :  decidable_wf,  decidable__false,  false_wf,  decidable__implies
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  lambdaFormation,  cut,  lemma_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  isect_memberEquality,  hypothesis,  independent_functionElimination,  because_Cache,  universeEquality

Latex:
\mforall{}[P:\mBbbP{}].  (Dec(P)  {}\mRightarrow{}  Dec(\mneg{}P))



Date html generated: 2016_05_13-PM-03_09_11
Last ObjectModification: 2016_01_06-PM-05_27_16

Theory : core_2


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