Nuprl Lemma : presheaf-fst_wf

[C:SmallCategory]. ∀[X:ps_context{j:l}(C)]. ∀[A:{X ⊢ _}]. ∀[B:{X.A ⊢ _}]. ∀[p:{X ⊢ _:Σ B}].  (p.1 ∈ {X ⊢ _:A})


Proof




Definitions occuring in Statement :  presheaf-fst: p.1 presheaf-sigma: Σ B psc-adjoin: X.A presheaf-term: {X ⊢ _:A} presheaf-type: {X ⊢ _} ps_context: __⊢ uall: [x:A]. B[x] member: t ∈ T small-category: SmallCategory
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T presheaf-fst: p.1 presheaf-term: {X ⊢ _:A} subtype_rel: A ⊆B presheaf-sigma: Σ B all: x:A. B[x] implies:  Q pi1: fst(t) presheaf-type: {X ⊢ _} and: P ∧ Q presheaf-type-ap-morph: (u f) presheaf-type-at: A(a) pi2: snd(t) prop:
Lemmas referenced :  presheaf-term_wf presheaf-sigma_wf presheaf-type_wf psc-adjoin_wf small-category-cumulativity-2 ps_context_cumulativity2 presheaf-type-cumulativity2 ps_context_wf small-category_wf presheaf_type_at_pair_lemma I_set_wf cat-ob_wf presheaf_type_ap_morph_pair_lemma cat-arrow_wf equal_wf psc-restriction_wf pi1_wf_top
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut sqequalRule sqequalHypSubstitution setElimination thin rename dependent_set_memberEquality_alt hypothesis axiomEquality equalityTransitivity equalitySymmetry universeIsType extract_by_obid isectElimination hypothesisEquality isect_memberEquality_alt isectIsTypeImplies inhabitedIsType instantiate applyEquality dependent_functionElimination Error :memTop,  lambdaEquality_alt lambdaFormation_alt productElimination equalityIstype independent_functionElimination hyp_replacement applyLambdaEquality because_Cache independent_pairEquality functionIsType

Latex:
\mforall{}[C:SmallCategory].  \mforall{}[X:ps\_context\{j:l\}(C)].  \mforall{}[A:\{X  \mvdash{}  \_\}].  \mforall{}[B:\{X.A  \mvdash{}  \_\}].  \mforall{}[p:\{X  \mvdash{}  \_:\mSigma{}  A  B\}].
    (p.1  \mmember{}  \{X  \mvdash{}  \_:A\})



Date html generated: 2020_05_20-PM-01_31_43
Last ObjectModification: 2020_04_02-PM-03_04_38

Theory : presheaf!models!of!type!theory


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