Nuprl Lemma : no-excluded-middle-quot-true

¬(∀P:ℙ. ⇃(P ∨ (↓¬P)))


Proof




Definitions occuring in Statement :  quotient: x,y:A//B[x; y],  prop: ℙ,  all: ∀x:A. B[x],  not: ¬A,  squash: ↓T,  or: P ∨ Q,  true: True
Definitions unfolded in proof :  uimplies: b supposing a,  so_apply: x[s1;s2],  so_lambda: λ2x y.t[x; y],  or: P ∨ Q,  prop: ℙ,  all: ∀x:A. B[x],  has-value: (a)↓,  uall: ∀[x:A]. B[x],  member: t ∈ T,  false: False,  implies: P ⇒ Q,  not: ¬A,  and: P ∧ Q,  quotient: x,y:A//B[x; y],  squash: ↓T,  top: Top
Lemmas referenced :  equiv_rel_true,  true_wf,  not_wf,  squash_wf,  quotient_wf,  sqle_wf_base,  is-exception_wf,  has-value_wf_base,  exception-not-bottom,  bottom_diverge,  istype-sqle,  bottom-sqle,  not_id_sqeq_bottom,  istype-void,  member-not
Rules used in proof :  independent_isectElimination,  Error :unionIsType,  Error :lambdaEquality_alt,  cumulativity,  unionEquality,  Error :universeIsType,  Error :functionIsType,  dependent_functionElimination,  equalitySymmetry,  equalityTransitivity,  Error :equalityIstype,  Error :inhabitedIsType,  universeEquality,  hypothesisEquality,  functionExtensionality,  applyEquality,  sqequalRule,  because_Cache,  baseClosed,  isectElimination,  voidElimination,  hypothesis,  thin,  independent_functionElimination,  sqequalHypSubstitution,  extract_by_obid,  introduction,  divergentSqle,  sqleReflexivity,  sqleRule,  cut,  rename,  Error :lambdaFormation_alt,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  productElimination,  promote_hyp,  pertypeElimination,  pointwiseFunctionalityForEquality,  Error :productIsType,  sqequalBase,  unionElimination,  imageElimination,  sqequalSqle,  Error :isect_memberEquality_alt

Latex:
\mneg{}(\mforall{}P:\mBbbP{}.  \00D9(P  \mvee{}  (\mdownarrow{}\mneg{}P)))



Date html generated: 2019_06_20-PM-00_32_43
Last ObjectModification: 2018_11_29-PM-04_55_48

Theory : quot_1


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