set XX = IncProjSp_of AS;
A1:
for a, b being POINT of (IncProjSp_of AS) ex A being LINE of (IncProjSp_of AS) st
( a on A & b on A )
by Lm4;
A2:
not for a being POINT of (IncProjSp_of AS)
for A being LINE of (IncProjSp_of AS) holds a on A
by Lm6;
A3:
for A being LINE of (IncProjSp_of AS) ex a, b, c being POINT of (IncProjSp_of AS) st
( a <> b & b <> c & c <> a & a on A & b on A & c on A )
proof
let A be
LINE of
(IncProjSp_of AS);
ex a, b, c being POINT of (IncProjSp_of AS) st
( a <> b & b <> c & c <> a & a on A & b on A & c on A )
consider a,
b,
c being
POINT of
(IncProjSp_of AS) such that A4:
a on A
and A5:
b on A
and A6:
c on A
and A7:
a <> b
and A8:
b <> c
and A9:
c <> a
by Lm3;
take
a
;
ex b, c being POINT of (IncProjSp_of AS) st
( a <> b & b <> c & c <> a & a on A & b on A & c on A )
take
b
;
ex c being POINT of (IncProjSp_of AS) st
( a <> b & b <> c & c <> a & a on A & b on A & c on A )
take
c
;
( a <> b & b <> c & c <> a & a on A & b on A & c on A )
thus
(
a <> b &
b <> c &
c <> a &
a on A &
b on A &
c on A )
by A4, A5, A6, A7, A8, A9;
verum
end;
A10:
for a, b, c, d, p, q being POINT of (IncProjSp_of AS)
for M, N, P, Q being LINE of (IncProjSp_of AS) st a on M & b on M & c on N & d on N & p on M & p on N & a on P & c on P & b on Q & d on Q & not p on P & not p on Q & M <> N holds
ex q being POINT of (IncProjSp_of AS) st
( q on P & q on Q )
by Lm12;
for a, b being POINT of (IncProjSp_of AS)
for A, K being LINE of (IncProjSp_of AS) st a on A & b on A & a on K & b on K & not a = b holds
A = K
by Lm2;
hence
( IncProjSp_of AS is partial & IncProjSp_of AS is linear & IncProjSp_of AS is up-2-dimensional & IncProjSp_of AS is up-3-rank & IncProjSp_of AS is Vebleian )
by A1, A2, A3, A10, INCPROJ:def 4, INCPROJ:def 5, INCPROJ:def 6, INCPROJ:def 7, INCPROJ:def 8; verum