reserve A,B,C for Ordinal,
  X,X1,Y,Y1,Z for set,a,b,b1,b2,x,y,z for object,
  R for Relation,
  f,g,h for Function,
  k,m,n for Nat;
reserve M,N for Cardinal;
reserve S for Sequence;

theorem Th38:
  n is finite & card n is finite
proof
  reconsider n as Element of omega by ORDINAL1:def 12;
  rng id n = n & dom id n = n by RELAT_1:45;
  hence thesis;
end;
