Nuprl Lemma : polymorphic-id-unique-sq

∀f:⋂T:Type. (T ⟶ T). (f ~ λx.x)


Proof




Definitions occuring in Statement :  all: ∀x:A. B[x],  lambda: λx.A[x],  isect: ⋂x:A. B[x],  function: x:A ⟶ B[x],  universe: Type,  sqequal: s ~ t
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  has-value: (a)↓,  uall: ∀[x:A]. B[x],  member: t ∈ T,  uimplies: b supposing a,  subtype_rel: A ⊆r B,  guard: {T},  or: P ∨ Q,  prop: ℙ,  so_lambda: λ2x.t[x],  so_apply: x[s],  sq_type: SQType(T),  it: ⋅,  false: False,  top: Top,  unit: Unit,  not: ¬A,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  squash: ↓T
Lemmas referenced :  value-type-has-value,  int-value-type,  equal-wf-base,  base_wf,  set_wf,  subtype_base_sq,  set_subtype_base,  subtype_rel_self,  equal_wf,  has-value_wf_base,  is-exception_wf,  unit_wf2,  it_wf,  unit_subtype_base,  equal-unit,  bottom-sqle,  equal-value-type,  bottom_diverge
Rules used in proof :  cut,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  callbyvalueApplyCases,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  intEquality,  independent_isectElimination,  hypothesis,  applyEquality,  equalityTransitivity,  equalitySymmetry,  lambdaEquality,  isectEquality,  universeEquality,  cumulativity,  functionEquality,  hypothesisEquality,  sqequalRule,  natural_numberEquality,  unionElimination,  instantiate,  because_Cache,  setEquality,  functionExtensionality,  dependent_set_memberEquality,  setElimination,  rename,  addLevel,  levelHypothesis,  dependent_functionElimination,  independent_functionElimination,  baseClosed,  axiomSqleEquality,  divergentSqle,  sqleReflexivity,  voidElimination,  sqequalSqle,  isect_memberEquality,  voidEquality,  pointwiseFunctionality,  sqequalAxiom,  sqequalExtensionalEquality,  independent_pairFormation,  sqequalIntensionalEquality,  imageMemberEquality

Latex:
\mforall{}f:\mcap{}T:Type.  (T  {}\mrightarrow{}  T).  (f  \msim{}  \mlambda{}x.x)



Date html generated: 2017_10_01-AM-09_07_17
Last ObjectModification: 2017_07_26-PM-04_46_45

Theory : general


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