reserve p,p1,p2,q1,q2 for Point of TOP-REAL 2,
  P1,P2 for Subset of TOP-REAL 2,
  f,f1,f2,g1,g2 for FinSequence of TOP-REAL 2,
  n,m,i,j,k for Nat,
  G,G1 for Go-board,
  x,y for set;

theorem
  for G,f1,f2 st 2 <= len f1 & 2 <= len f2 & f1 is_sequence_on G & f2
  is_sequence_on G & f1/.1 in rng Line(G,1) & f1/.len f1 in rng Line(G,len G) &
f2/.1 in rng Col(G,1) & f2/.len f2 in rng Col(G,width G) holds L~f1 meets L~f2
  by Th2;
