reserve T for non empty TopSpace,
  a, b, c, d for Point of T;

theorem Th68:
  for x being Point of I[01] holds [1,x] in ICC
proof
  let x be Point of I[01];
  1 is Point of I[01] & x <= 2 * 1 - 1 by BORSUK_1:43;
  hence thesis by Def10;
end;
