Nuprl Lemma : TC-ind-ext

[Dom:Type]. ∀[B:Dom ⟶ ℙ]. ∀[R:Dom ⟶ Dom ⟶ ℙ].
  ((∀x,y:Dom.  ((R y)  (B x)  (B y)))  (∀x,y:Dom.  (TC(λa,b.R b)(x,y)  (B x)  (B y))))


Proof




Definitions occuring in Statement :  TC: TC(λx,y.F[x; y])(a,b) uall: [x:A]. B[x] prop: all: x:A. B[x] implies:  Q apply: a function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  member: t ∈ T TC-ind transitive-closure-induction transitive-closure-minimal spreadn: spread3 uall: [x:A]. B[x] so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]) so_apply: x[s1;s2;s3;s4] top: Top uimplies: supposing a strict4: strict4(F) and: P ∧ Q all: x:A. B[x] implies:  Q has-value: (a)↓ prop: guard: {T} or: P ∨ Q squash: T so_lambda: λ2y.t[x; y] so_apply: x[s1;s2]
Lemmas referenced :  TC-ind transitive-closure-induction transitive-closure-minimal is-exception_wf base_wf has-value_wf_base lifting-strict-spread
Rules used in proof :  introduction cut sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity instantiate extract_by_obid hypothesis sqequalHypSubstitution sqequalRule lemma_by_obid isectElimination thin baseClosed isect_memberEquality voidElimination voidEquality independent_isectElimination independent_pairFormation lambdaFormation callbyvalueApply baseApply closedConclusion hypothesisEquality applyExceptionCases inrFormation imageMemberEquality imageElimination exceptionSqequal inlFormation equalityTransitivity equalitySymmetry

Latex:
\mforall{}[Dom:Type].  \mforall{}[B:Dom  {}\mrightarrow{}  \mBbbP{}].  \mforall{}[R:Dom  {}\mrightarrow{}  Dom  {}\mrightarrow{}  \mBbbP{}].
    ((\mforall{}x,y:Dom.    ((R  x  y)  {}\mRightarrow{}  (B  x)  {}\mRightarrow{}  (B  y)))  {}\mRightarrow{}  (\mforall{}x,y:Dom.    (TC(\mlambda{}a,b.R  a  b)(x,y)  {}\mRightarrow{}  (B  x)  {}\mRightarrow{}  (B  y))))



Date html generated: 2016_05_16-AM-09_07_52
Last ObjectModification: 2016_01_17-AM-09_53_25

Theory : first-order!and!ancestral!logic


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