Nuprl Lemma : equipollent_transitivity

∀[A,B,C:Type].  (A ~ B ⇒ B ~ C ⇒ A ~ C)


Proof




Definitions occuring in Statement :  equipollent: A ~ B,  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  universe: Type
Definitions unfolded in proof :  equipollent: A ~ B,  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  exists: ∃x:A. B[x],  member: t ∈ T,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  biject: Bij(A;B;f),  and: P ∧ Q,  cand: A c∧ B,  surject: Surj(A;B;f),  inject: Inj(A;B;f),  all: ∀x:A. B[x],  guard: {T},  compose: f o g,  squash: ↓T,  true: True,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q
Lemmas referenced :  exists_wf,  biject_wf,  compose_wf,  equal_wf,  squash_wf,  true_wf,  iff_weakening_equal
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation,  lambdaFormation,  sqequalHypSubstitution,  productElimination,  thin,  cut,  introduction,  extract_by_obid,  isectElimination,  functionEquality,  cumulativity,  hypothesisEquality,  lambdaEquality,  functionExtensionality,  applyEquality,  hypothesis,  universeEquality,  rename,  dependent_pairFormation,  independent_pairFormation,  dependent_functionElimination,  independent_functionElimination,  imageElimination,  equalityTransitivity,  equalitySymmetry,  natural_numberEquality,  imageMemberEquality,  baseClosed,  independent_isectElimination

Latex:
\mforall{}[A,B,C:Type].    (A  \msim{}  B  {}\mRightarrow{}  B  \msim{}  C  {}\mRightarrow{}  A  \msim{}  C)



Date html generated: 2017_04_17-AM-09_30_53
Last ObjectModification: 2017_02_27-PM-05_31_06

Theory : equipollence!!cardinality!


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