Nuprl Lemma : dl-lt_functionality

∀x,y,x',y':dl-Obj().  ((↑dlo_eq(x;x')) ⇒ (↑dlo_eq(y;y')) ⇒ x ≤ y = x' ≤ y')


Proof




Definitions occuring in Statement :  dlo_le: a ≤ b,  dlo_eq: dlo_eq(a;b),  dl-Obj: dl-Obj(),  assert: ↑b,  bool: 𝔹,  all: ∀x:A. B[x],  implies: P ⇒ Q,  equal: s = t ∈ T
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  iff: P ⇐⇒ Q,  and: P ∧ Q,  squash: ↓T,  uall: ∀[x:A]. B[x],  true: True
Lemmas referenced :  assert-dlo_eq,  dlo_le_wf,  istype-assert,  dlo_eq_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  hypothesis,  productElimination,  independent_functionElimination,  applyEquality,  lambdaEquality_alt,  imageElimination,  isectElimination,  because_Cache,  natural_numberEquality,  sqequalRule,  imageMemberEquality,  baseClosed

Latex:
\mforall{}x,y,x',y':dl-Obj().    ((\muparrow{}dlo\_eq(x;x'))  {}\mRightarrow{}  (\muparrow{}dlo\_eq(y;y'))  {}\mRightarrow{}  x  \mleq{}  y  =  x'  \mleq{}  y')



Date html generated: 2019_10_15-AM-11_44_06
Last ObjectModification: 2019_04_11-PM-02_12_34

Theory : dynamic!logic


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