Nuprl Lemma : projective-lines-exist
∀e:EuclideanParPlane. ∀p1,p2:Point + Line.
  (proj-point-sep(e;p1;p2) 
⇒ (∃l:Line?. ((¬pp-sep(e;p1;l)) ∧ (¬pp-sep(e;p2;l)))))
Proof
Definitions occuring in Statement : 
proj-point-sep: proj-point-sep(eu;p;q)
, 
pp-sep: pp-sep(eu;p;l)
, 
euclidean-parallel-plane: EuclideanParPlane
, 
geo-line: Line
, 
geo-point: Point
, 
all: ∀x:A. B[x]
, 
exists: ∃x:A. B[x]
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
, 
unit: Unit
, 
union: left + right
Definitions unfolded in proof : 
false: False
, 
not: ¬A
, 
geo-Aparallel: l || m
, 
rev_implies: P 
⇐ Q
, 
iff: P 
⇐⇒ Q
, 
euclidean-parallel-plane: EuclideanParPlane
, 
pi2: snd(t)
, 
pi1: fst(t)
, 
geo-plsep: p # l
, 
pp-sep: pp-sep(eu;p;l)
, 
cand: A c∧ B
, 
and: P ∧ Q
, 
geo-line: Line
, 
exists: ∃x:A. B[x]
, 
uimplies: b supposing a
, 
guard: {T}
, 
subtype_rel: A ⊆r B
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
member: t ∈ T
, 
proj-point-sep: proj-point-sep(eu;p;q)
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
Lemmas referenced : 
false_wf, 
it_wf, 
geoline-subtype1, 
geo-Aparallel_sym, 
geo-incident-not-plsep, 
Euclid-parallel-exists, 
not-lsep-iff-colinear, 
basic-geometry_wf, 
euclidean-plane-subtype-basic, 
geo-colinear-same, 
pp-sep_wf, 
not_wf, 
unit_wf2, 
geo-sep_wf, 
geo-line_wf, 
geo-primitives_wf, 
euclidean-plane-structure_wf, 
euclidean-plane_wf, 
euclidean-parallel-plane_wf, 
subtype_rel_transitivity, 
euclidean-planes-subtype, 
euclidean-plane-subtype, 
euclidean-plane-structure-subtype, 
geo-point_wf, 
proj-point-sep_wf
Rules used in proof : 
voidElimination, 
inrEquality, 
independent_functionElimination, 
productElimination, 
setElimination, 
independent_pairFormation, 
productEquality, 
dependent_pairEquality, 
inlEquality, 
dependent_pairFormation, 
rename, 
because_Cache, 
dependent_functionElimination, 
sqequalRule, 
independent_isectElimination, 
instantiate, 
applyEquality, 
unionEquality, 
hypothesis, 
hypothesisEquality, 
isectElimination, 
extract_by_obid, 
introduction, 
cut, 
sqequalHypSubstitution, 
thin, 
unionElimination, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}e:EuclideanParPlane.  \mforall{}p1,p2:Point  +  Line.
    (proj-point-sep(e;p1;p2)  {}\mRightarrow{}  (\mexists{}l:Line?.  ((\mneg{}pp-sep(e;p1;l))  \mwedge{}  (\mneg{}pp-sep(e;p2;l)))))
Date html generated:
2018_05_22-PM-01_14_26
Last ObjectModification:
2018_05_21-PM-02_39_11
Theory : euclidean!plane!geometry
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