Nuprl Lemma : finite-set-type

∀[T:Type]. ∀[P:T ⟶ ℙ].  ((∀x:T. SqStable(P[x])) ⇒ (finite-type({x:T| P[x]} ) ⇐⇒ ∃L:T List. ∀x:T. (P[x] ⇐⇒ (x ∈ L))))


Proof




Definitions occuring in Statement :  finite-type: finite-type(T),  l_member: (x ∈ l),  list: T List,  sq_stable: SqStable(P),  uall: ∀[x:A]. B[x],  prop: ℙ,  so_apply: x[s],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  iff: P ⇐⇒ Q,  implies: P ⇒ Q,  set: {x:A| B[x]} ,  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  iff: P ⇐⇒ Q,  and: P ∧ Q,  exists: ∃x:A. B[x],  member: t ∈ T,  subtype_rel: A ⊆r B,  so_apply: x[s],  uimplies: b supposing a,  all: ∀x:A. B[x],  rev_implies: P ⇐ Q,  prop: ℙ,  so_lambda: λ2x.t[x],  l_member: (x ∈ l),  cand: A c∧ B,  nat: ℕ,  ge: i ≥ j ,  decidable: Dec(P),  or: P ∨ Q,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  false: False,  top: Top,  squash: ↓T,  sq_stable: SqStable(P),  guard: {T},  int_seg: {i..j-},  lelt: i ≤ j < k
Lemmas referenced :  subtype_rel_list,  l_member_wf,  list_wf,  subtype_rel_self,  finite-type-iff-list,  finite-type_wf,  sq_stable_wf,  l_member-settype,  select_wf,  nat_properties,  decidable__le,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformle_wf,  itermConstant_wf,  itermVar_wf,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_not_lemma,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  list-set-type2,  l_all_iff,  less_than_wf,  length_wf,  select_member,  le_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  Error :lambdaFormation_alt,  cut,  independent_pairFormation,  sqequalHypSubstitution,  productElimination,  thin,  Error :dependent_pairFormation_alt,  hypothesisEquality,  applyEquality,  introduction,  extract_by_obid,  isectElimination,  setEquality,  hypothesis,  because_Cache,  sqequalRule,  independent_isectElimination,  Error :lambdaEquality_alt,  setElimination,  rename,  Error :setIsType,  Error :universeIsType,  Error :inhabitedIsType,  Error :functionIsType,  Error :productIsType,  instantiate,  universeEquality,  independent_functionElimination,  promote_hyp,  dependent_functionElimination,  Error :dependent_set_memberEquality_alt,  natural_numberEquality,  unionElimination,  approximateComputation,  int_eqEquality,  Error :isect_memberEquality_alt,  voidElimination,  hyp_replacement,  equalitySymmetry,  applyLambdaEquality,  imageMemberEquality,  baseClosed,  imageElimination,  equalityTransitivity,  Error :equalityIsType1

Latex:
\mforall{}[T:Type].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbP{}].
    ((\mforall{}x:T.  SqStable(P[x]))  {}\mRightarrow{}  (finite-type(\{x:T|  P[x]\}  )  \mLeftarrow{}{}\mRightarrow{}  \mexists{}L:T  List.  \mforall{}x:T.  (P[x]  \mLeftarrow{}{}\mRightarrow{}  (x  \mmember{}  L))))



Date html generated: 2019_06_20-PM-01_32_36
Last ObjectModification: 2018_10_15-PM-01_40_42

Theory : list_1


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