reserve X for non empty 1-sorted;
reserve A, A1, A2, B1, B2 for Subset of X;
reserve X for non empty TopSpace;
reserve A, A1, A2, B1, B2 for Subset of X;
reserve X for non empty 1-sorted;
reserve A, A1, A2, B1, B2 for Subset of X;
reserve X for non empty TopSpace,
  A1, A2 for Subset of X;
reserve X0 for non empty SubSpace of X,
  B1, B2 for Subset of X0;
reserve X0, X1, X2, Y1, Y2 for non empty SubSpace of X;

theorem Th30:
  X0,X0 do_not_constitute_a_decomposition
proof
  reconsider A0 = the carrier of X0 as Subset of X by TSEP_1:1;
  now
    take A1 = A0, A2 = A0;
    thus A1 = the carrier of X0 & A2 = the carrier of X0 & A1,A2
    do_not_constitute_a_decomposition by Th7;
  end;
  hence thesis;
end;
