Nuprl Lemma : istype-inr-sqeq-inl

∀[a,b:Top].  istype(inr b  ~ inl a)


Proof




Definitions occuring in Statement :  istype: istype(T),  uall: ∀[x:A]. B[x],  top: Top,  inr: inr x ,  inl: inl x,  sqequal: s ~ t
Definitions unfolded in proof :  false: False,  not: ¬A,  uall: ∀[x:A]. B[x],  member: t ∈ T,  squash: ↓T,  prop: ℙ,  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  rev_implies: P ⇐ Q,  true: True,  subtype_rel: A ⊆r B
Lemmas referenced :  member_wf,  squash_wf,  true_wf,  istype-universe,  not-inl-sqeq-inr,  istype-sqequal,  equal_wf,  subtype_rel_self,  istype-top
Rules used in proof :  voidElimination,  independent_functionElimination,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  Error :isect_memberFormation_alt,  Error :universeIsType,  pointwiseFunctionality,  sqequalExtensionalEquality,  cut,  applyEquality,  thin,  instantiate,  Error :lambdaEquality_alt,  sqequalHypSubstitution,  imageElimination,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  equalityTransitivity,  hypothesis,  equalitySymmetry,  universeEquality,  independent_pairFormation,  Error :lambdaFormation_alt,  because_Cache,  sqequalRule,  baseApply,  closedConclusion,  baseClosed,  imageMemberEquality,  natural_numberEquality,  Error :inhabitedIsType

Latex:
\mforall{}[a,b:Top].    istype(inr  b    \msim{}  inl  a)



Date html generated: 2019_06_20-PM-01_04_24
Last ObjectModification: 2019_06_20-PM-01_01_40

Theory : union


Home Index