Nuprl Lemma : equal-bnot

[x,y:𝔹].  uiff(x = ¬by;¬y)


Proof




Definitions occuring in Statement :  bnot: ¬bb bool: 𝔹 uiff: uiff(P;Q) uall: [x:A]. B[x] not: ¬A equal: t ∈ T
Definitions unfolded in proof :  member: t ∈ T all: x:A. B[x] implies:  Q bool: 𝔹 unit: Unit it: btrue: tt uall: [x:A]. B[x] uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a bnot: ¬bb ifthenelse: if then else fi  not: ¬A false: False prop: assert: b bfalse: ff iff: ⇐⇒ Q rev_implies:  Q exists: x:A. B[x] or: P ∨ Q sq_type: SQType(T) guard: {T} decidable: Dec(P)
Lemmas referenced :  eqtt_to_assert btrue_neq_bfalse equal-wf-T-base bool_wf iff_imp_equal_bool bfalse_wf assert_elim assert_wf false_wf not_wf eqff_to_assert equal_wf bool_cases_sqequal subtype_base_sq bool_subtype_base assert-bnot assert_witness assert_of_bnot bnot_wf uiff_wf iff_weakening_uiff decidable__assert
Rules used in proof :  cut sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity hypothesisEquality thin because_Cache lambdaFormation sqequalHypSubstitution unionElimination equalityElimination introduction extract_by_obid isectElimination hypothesis productElimination independent_isectElimination sqequalRule independent_pairFormation isect_memberFormation equalityTransitivity equalitySymmetry independent_functionElimination voidElimination baseClosed lambdaEquality dependent_functionElimination addLevel levelHypothesis dependent_pairFormation promote_hyp instantiate cumulativity functionEquality independent_pairEquality isect_memberEquality axiomEquality

Latex:
\mforall{}[x,y:\mBbbB{}].    uiff(x  =  \mneg{}\msubb{}y;\mneg{}x  =  y)



Date html generated: 2017_10_01-AM-09_12_43
Last ObjectModification: 2017_07_26-PM-04_48_20

Theory : general


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