Nuprl Lemma : not-not-inner-pasch
∀g:OrientedPlane. ∀a,b,c:Point. ∀p:{p:Point| B(apc)} . ∀q:{q:Point| B(bqc)} .  (¬¬(∃x:Point. (B(pxb) ∧ B(qxa))))
Proof
Definitions occuring in Statement : 
oriented-plane: OrientedPlane, 
geo-between: B(abc), 
geo-point: Point, 
all: ∀x:A. B[x], 
exists: ∃x:A. B[x], 
not: ¬A, 
and: P ∧ Q, 
set: {x:A| B[x]} 
Definitions unfolded in proof : 
cand: A c∧ B, 
oriented-plane: OrientedPlane, 
or: P ∨ Q, 
prop: ℙ, 
uimplies: b supposing a, 
guard: {T}, 
subtype_rel: A ⊆r B, 
uall: ∀[x:A]. B[x], 
and: P ∧ Q, 
member: t ∈ T, 
exists: ∃x:A. B[x], 
false: False, 
implies: P ⇒ Q, 
not: ¬A, 
all: ∀x:A. B[x], 
stable: Stable{P}, 
geo-eq: a ≡ b, 
rev_implies: P ⇐ Q, 
iff: P ⇐⇒ Q, 
geo-strict-between: a-b-c, 
squash: ↓T, 
geo-between: B(abc), 
sq_stable: SqStable(P), 
euclidean-plane: EuclideanPlane, 
sq_exists: ∃x:A [B[x]], 
geo-colinear: Colinear(a;b;c), 
basic-geometry-: BasicGeometry-
Latex:
\mforall{}g:OrientedPlane.  \mforall{}a,b,c:Point.  \mforall{}p:\{p:Point|  B(apc)\}  .  \mforall{}q:\{q:Point|  B(bqc)\}  .
    (\mneg{}\mneg{}(\mexists{}x:Point.  (B(pxb)  \mwedge{}  B(qxa))))
Date html generated:
2020_05_20-AM-09_50_34
Last ObjectModification:
2019_12_20-PM-08_46_04
Theory : euclidean!plane!geometry
Home
Index