Nuprl Lemma : inject-subtype

[C,A:Type].  ∀[B:Type]. ∀[f:A ⟶ B].  Inj(C;B;f) supposing Inj(A;B;f) supposing strong-subtype(C;A)


Proof




Definitions occuring in Statement :  strong-subtype: strong-subtype(A;B) inject: Inj(A;B;f) uimplies: supposing a uall: [x:A]. B[x] function: x:A ⟶ B[x] universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a inject: Inj(A;B;f) all: x:A. B[x] subtype_rel: A ⊆B strong-subtype: strong-subtype(A;B) cand: c∧ B implies:  Q label: ...$L... t guard: {T} prop:
Lemmas referenced :  strong-subtype-eq1 inject_wf strong-subtype_wf istype-universe
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut sqequalHypSubstitution lambdaFormation_alt hypothesis dependent_functionElimination thin hypothesisEquality applyEquality productElimination sqequalRule independent_functionElimination extract_by_obid isectElimination because_Cache independent_isectElimination equalityIstype universeIsType lambdaEquality_alt axiomEquality functionIsTypeImplies inhabitedIsType isect_memberEquality_alt isectIsTypeImplies functionIsType instantiate universeEquality

Latex:
\mforall{}[C,A:Type].    \mforall{}[B:Type].  \mforall{}[f:A  {}\mrightarrow{}  B].    Inj(C;B;f)  supposing  Inj(A;B;f)  supposing  strong-subtype(C;A)



Date html generated: 2020_05_19-PM-09_36_21
Last ObjectModification: 2020_01_25-PM-08_00_58

Theory : subtype_1


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