 reserve a,b,c,x for Real;
 reserve C for non empty set;

theorem CEmpty:
  Core EMF C = {}
  proof
    thus Core EMF C c= {}
    proof
      let x be object;
      assume x in Core EMF C; then
      consider xx being Element of C such that
A1:   x = xx & (EMF C).xx = 1;
      thus thesis by A1,FUNCT_3:def 3;
    end;
    thus thesis;
  end;
