Nuprl Lemma : W-uniform-measure-induction

[T,A:Type]. ∀[B:A ⟶ Type]. ∀[measure:T ⟶ W(A;a.B[a])]. ∀[P:T ⟶ ℙ].
  ((∀[i:T]. ((∀[j:{j:T| measure[j] <  measure[i]} ]. P[j])  P[i]))  (∀[i:T]. P[i]))


Proof




Definitions occuring in Statement :  Wcmp: Wcmp(A;a.B[a];leq) W: W(A;a.B[a]) bfalse: ff uall: [x:A]. B[x] prop: infix_ap: y so_apply: x[s] implies:  Q set: {x:A| B[x]}  function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  member: t ∈ T uall: [x:A]. B[x] all: x:A. B[x] implies:  Q so_lambda: λ2x.t[x] so_apply: x[s] subtype_rel: A ⊆B prop: uimplies: supposing a Wcmp: Wcmp(A;a.B[a];leq) Wsup: Wsup(a;b) infix_ap: y ifthenelse: if then else fi  bfalse: ff exists: x:A. B[x] guard: {T} top: Top and: P ∧ Q pcw-pp-barred: Barred(pp) nat: int_seg: {i..j-} lelt: i ≤ j < k decidable: Dec(P) or: P ∨ Q iff: ⇐⇒ Q not: ¬A rev_implies:  Q false: False uiff: uiff(P;Q) subtract: m le: A ≤ B less_than': less_than'(a;b) true: True cw-step: cw-step(A;a.B[a]) pcw-step: pcw-step(P;p.A[p];p,a.B[p; a];p,a,b.C[p; a; b]) spreadn: spread3 less_than: a < b squash: T isr: isr(x) assert: b btrue: tt ext-eq: A ≡ B unit: Unit it: so_lambda: λ2y.t[x; y] so_apply: x[s1;s2] so_lambda: so_lambda(x,y,z.t[x; y; z]) so_apply: x[s1;s2;s3] ext-family: F ≡ G pi1: fst(t) nat_plus: + istype: istype(T) W-rel: W-rel(A;a.B[a];w) param-W-rel: param-W-rel(P;p.A[p];p,a.B[p; a];p,a,b.C[p; a; b];par;w) pcw-steprel: StepRel(s1;s2) pi2: snd(t) isl: isl(x) pcw-step-agree: StepAgree(s;p1;w) cand: c∧ B sq_type: SQType(T) sq_stable: SqStable(P)
Lemmas referenced :  infix_ap_wf W_wf Wcmp_wf bfalse_wf ycomb_wf_trivial Wleq_weakening2 ycomb-unroll istype-void btrue_wf Wsup_wf W-elimination-facts subtype_rel_self int_seg_wf subtract_wf decidable__le istype-false not-le-2 less-iff-le condition-implies-le minus-one-mul zero-add minus-one-mul-top nat_wf minus-add istype-int minus-minus add-associates add-swap add-commutes add_functionality_wrt_le add-zero le-add-cancel decidable__lt not-lt-2 add-mul-special zero-mul le-add-cancel-alt lelt_wf istype-top true_wf add-subtract-cancel W-ext param-co-W-ext unit_wf2 it_wf param-co-W_wf less_than_wf top_wf pcw-steprel_wf false_wf subtype_rel_dep_function subtype_base_sq set_subtype_base le_wf int_subtype_base minus-zero le-add-cancel2 decidable__int_equal not-equal-2 subtype_rel_function int_seg_subtype sq_stable__le Wcmp_transitivity
Rules used in proof :  introduction sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity sqequalRule Error :isect_memberEquality_alt,  cut Error :lambdaFormation_alt,  rename Error :universeIsType,  hypothesisEquality sqequalHypSubstitution hypothesis Error :isectIsType,  Error :functionIsType,  Error :setIsType,  Error :inhabitedIsType,  thin instantiate extract_by_obid isectElimination cumulativity Error :lambdaEquality_alt,  applyEquality functionExtensionality because_Cache equalityTransitivity equalitySymmetry universeEquality setElimination Error :functionExtensionality_alt,  dependent_functionElimination independent_functionElimination independent_isectElimination productElimination voidElimination strong_bar_Induction natural_numberEquality Error :dependent_set_memberEquality_alt,  independent_pairFormation unionElimination addEquality minusEquality lessCases Error :isect_memberFormation_alt,  axiomSqEquality imageMemberEquality baseClosed imageElimination axiomEquality Error :equalityIsType1,  int_eqReduceTrueSq promote_hyp hypothesis_subsumption equalityElimination Error :dependent_pairEquality_alt,  Error :inlEquality_alt,  Error :unionIsType,  productEquality unionEquality hyp_replacement applyLambdaEquality intEquality

Latex:
\mforall{}[T,A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[measure:T  {}\mrightarrow{}  W(A;a.B[a])].  \mforall{}[P:T  {}\mrightarrow{}  \mBbbP{}].
    ((\mforall{}[i:T].  ((\mforall{}[j:\{j:T|  measure[j]  <    measure[i]\}  ].  P[j])  {}\mRightarrow{}  P[i]))  {}\mRightarrow{}  (\mforall{}[i:T].  P[i]))



Date html generated: 2019_06_20-PM-00_36_39
Last ObjectModification: 2018_10_01-PM-03_05_32

Theory : co-recursion


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