Nuprl Lemma : pgeo-join-to-line
∀g:BasicProjectivePlane. ∀p,q:Point. ∀l:Line. ∀s:p ≠ q.  (p I l 
⇒ q I l 
⇒ p ∨ q ≡ l)
Proof
Definitions occuring in Statement : 
basic-projective-plane: BasicProjectivePlane
, 
pgeo-join: p ∨ q
, 
pgeo-leq: a ≡ b
, 
pgeo-psep: 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 : 
pgeo-peq: a ≡ b
, 
guard: {T}
, 
false: False
, 
cand: A c∧ B
, 
uimplies: b supposing a
, 
prop: ℙ
, 
and: P ∧ Q
, 
subtype_rel: A ⊆r B
, 
basic-projective-plane: BasicProjectivePlane
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
not: ¬A
, 
pgeo-leq: a ≡ b
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
Lemmas referenced : 
pgeo-point_wf, 
pgeo-psep_wf, 
pgeo-primitives_wf, 
projective-plane-structure_wf, 
basic-projective-plane_wf, 
subtype_rel_transitivity, 
basic-projective-plane-subtype, 
projective-plane-structure_subtype, 
pgeo-lsep_wf, 
pgeo-leq_wf, 
pgeo-peq_wf, 
incident-join-second, 
incident-join-first, 
pgeo-incident_wf, 
pgeo-line_wf, 
pgeo-join_wf, 
Unique
Rules used in proof : 
instantiate, 
voidElimination, 
independent_functionElimination, 
independent_pairFormation, 
independent_isectElimination, 
productEquality, 
sqequalRule, 
setEquality, 
lambdaEquality, 
applyEquality, 
hypothesis, 
because_Cache, 
rename, 
setElimination, 
isectElimination, 
hypothesisEquality, 
thin, 
dependent_functionElimination, 
sqequalHypSubstitution, 
extract_by_obid, 
introduction, 
cut, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}g:BasicProjectivePlane.  \mforall{}p,q:Point.  \mforall{}l:Line.  \mforall{}s:p  \mneq{}  q.    (p  I  l  {}\mRightarrow{}  q  I  l  {}\mRightarrow{}  p  \mvee{}  q  \mequiv{}  l)
Date html generated:
2018_05_22-PM-00_35_39
Last ObjectModification:
2017_11_25-AM-09_05_06
Theory : euclidean!plane!geometry
Home
Index