Nuprl Lemma : l-all-iff

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


Proof




Definitions occuring in Statement :  l-all: x∈L.P[x] l_all: (∀x∈L.P[x]) l_member: (x ∈ l) list: List uall: [x:A]. B[x] prop: so_apply: x[s] all: x:A. B[x] iff: ⇐⇒ Q set: {x:A| B[x]}  function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] member: t ∈ T so_lambda: λ2x.t[x] prop: so_apply: x[s] iff: ⇐⇒ Q rev_implies:  Q implies:  Q and: P ∧ Q l-all: x∈L.P[x] top: Top true: True subtype_rel: A ⊆B uimplies: supposing a not: ¬A false: False
Lemmas referenced :  list_induction uall_wf iff_wf l-all_wf l_member_wf l_all_wf2 list_wf reduce_nil_lemma l_all_nil true_wf nil_wf null_nil_lemma btrue_wf member-implies-null-eq-bfalse btrue_neq_bfalse reduce_cons_lemma subtype_rel_self l_all_cons cons_wf list-subtype
Rules used in proof :  cut sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation lambdaFormation thin instantiate introduction extract_by_obid sqequalHypSubstitution isectElimination cumulativity hypothesisEquality sqequalRule lambdaEquality functionEquality universeEquality applyEquality setElimination rename hypothesis setEquality because_Cache independent_functionElimination dependent_functionElimination isect_memberEquality voidElimination voidEquality independent_pairFormation natural_numberEquality independent_isectElimination equalityTransitivity equalitySymmetry productElimination productEquality addLevel

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



Date html generated: 2019_10_15-AM-11_08_59
Last ObjectModification: 2018_08_25-PM-00_08_55

Theory : general


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