Nuprl Lemma : ext-eq-implies-biject

∀[T,S:Type].  (T ≡ S ⇒ Bij(S;T;λx.x))


Proof




Definitions occuring in Statement :  biject: Bij(A;B;f),  ext-eq: A ≡ B,  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  lambda: λx.A[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  member: t ∈ T,  prop: ℙ,  biject: Bij(A;B;f),  and: P ∧ Q,  inject: Inj(A;B;f),  all: ∀x:A. B[x],  guard: {T},  uimplies: b supposing a,  subtype_rel: A ⊆r B,  surject: Surj(A;B;f),  exists: ∃x:A. B[x]
Lemmas referenced :  ext-eq_wf,  subtype_rel_weakening,  equal_functionality_wrt_subtype_rel2,  equal_wf,  ext-eq_inversion
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  cumulativity,  hypothesisEquality,  hypothesis,  universeEquality,  independent_pairFormation,  sqequalRule,  independent_isectElimination,  equalityTransitivity,  equalitySymmetry,  independent_functionElimination,  applyEquality,  dependent_pairFormation

Latex:
\mforall{}[T,S:Type].    (T  \mequiv{}  S  {}\mRightarrow{}  Bij(S;T;\mlambda{}x.x))



Date html generated: 2016_10_21-AM-09_40_40
Last ObjectModification: 2016_08_07-PM-06_29_39

Theory : fun_1


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