let K, L be Block of (VeroneseSpace S); :: according to PENCIL_1:def 7 :: thesis: ( not 2 c= card (K /\ L) or K = L )
assume
2 c= card (K /\ L)
; :: thesis: K = L
then consider a, b being set such that
A1:
( a in K /\ L & b in K /\ L & a <> b )
by PENCIL_1:2;
A2:
( a in K & a in L & b in K & b in L )
by A1, XBOOLE_0:def 4;
then A3:
not the topology of (VeroneseSpace S) is empty
by SUBSET_1:def 2;
then consider t being set , k being Subset of S such that
A4:
( t in the carrier of S & k in the topology of S & K = PairSet t,k )
by Def10;
consider s being set , l being Subset of S such that
A5:
( s in the carrier of S & l in the topology of S & L = PairSet s,l )
by A3, Def10;
consider x being set such that
A6:
( x in k & a = {t,x} )
by A2, A4, Def9;
consider y being set such that
A7:
( y in k & b = {t,y} )
by A2, A4, Def9;
consider z being set such that
A8:
( z in l & a = {s,z} )
by A2, A5, Def9;
consider w being set such that
A9:
( w in l & b = {s,w} )
by A2, A5, Def9;
A10:
( ( t = s or t = z ) & ( t = s or t = w ) )
by A6, A7, A8, A9, ZFMISC_1:10;
then
( x in k /\ l & y in k /\ l )
by A6, A7, A8, A9, A11, XBOOLE_0:def 4;
then
2 c= card (k /\ l)
by A1, A6, A7, PENCIL_1:2;
hence
K = L
by A1, A4, A5, A8, A9, A10, PENCIL_1:def 7; :: thesis: verum