Nuprl Lemma : pgeo-peq-preserves-incidence

∀g:ProjectivePlane. ∀a,b:Point. ∀l:Line.  (a I l ⇒ a ≡ b ⇒ b I l)


Proof




Definitions occuring in Statement :  projective-plane: ProjectivePlane,  pgeo-peq: a ≡ b,  pgeo-incident: a I b,  pgeo-line: Line,  pgeo-point: Point,  all: ∀x:A. B[x],  implies: P ⇒ Q
Definitions unfolded in proof :  uimplies: b supposing a,  guard: {T},  false: False,  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  prop: ℙ,  cand: A c∧ B,  and: P ∧ Q,  member: t ∈ T,  exists: ∃x:A. B[x],  pgeo-psep: a ≠ b,  pgeo-peq: a ≡ b,  not: ¬A,  pgeo-incident: a I b,  implies: P ⇒ Q,  all: ∀x:A. B[x]
Lemmas referenced :  pgeo-point_wf,  pgeo-line_wf,  pgeo-primitives_wf,  projective-plane-structure_wf,  basic-projective-plane_wf,  projective-plane_wf,  subtype_rel_transitivity,  projective-plane-subtype,  basic-projective-plane-subtype,  projective-plane-structure_subtype,  pgeo-peq_wf,  pgeo-plsep_wf,  pgeo-incident_wf
Rules used in proof :  independent_isectElimination,  instantiate,  voidElimination,  sqequalRule,  because_Cache,  applyEquality,  isectElimination,  extract_by_obid,  introduction,  productEquality,  independent_pairFormation,  hypothesis,  cut,  hypothesisEquality,  dependent_pairFormation,  thin,  independent_functionElimination,  sqequalHypSubstitution,  lambdaFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}g:ProjectivePlane.  \mforall{}a,b:Point.  \mforall{}l:Line.    (a  I  l  {}\mRightarrow{}  a  \mequiv{}  b  {}\mRightarrow{}  b  I  l)



Date html generated: 2018_05_22-PM-00_43_55
Last ObjectModification: 2017_11_17-PM-00_07_50

Theory : euclidean!plane!geometry


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