reserve fi,psi for Ordinal-Sequence,
  A,A1,B,C,D for Ordinal,
  X,Y for set,
  x,y for object;

theorem
  X c= A implies union X is epsilon-transitive epsilon-connected set
proof
  assume X c= A;
  then for x st x in X holds x is Ordinal;
  hence thesis by ORDINAL1:23;
end;
