Nuprl Lemma : pi1_wf

∀[A:Type]. ∀[B:A ⟶ Type]. ∀[p:a:A × B[a]].  (fst(p) ∈ A)


Proof




Definitions occuring in Statement :  uall: ∀[x:A]. B[x],  so_apply: x[s],  pi1: fst(t),  member: t ∈ T,  function: x:A ⟶ B[x],  product: x:A × B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  pi1: fst(t),  so_apply: x[s]
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  productElimination,  thin,  sqequalRule,  hypothesisEquality,  sqequalHypSubstitution,  hypothesis,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  productEquality,  applyEquality,  isect_memberEquality,  isectElimination,  because_Cache,  functionEquality,  cumulativity,  universeEquality

Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[p:a:A  \mtimes{}  B[a]].    (fst(p)  \mmember{}  A)



Date html generated: 2016_05_13-PM-03_08_28
Last ObjectModification: 2016_01_06-PM-05_27_33

Theory : core_2


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