1st order logic (lisp 1.5); 2nd order logic (scheme); 3rd order logic (emacs); ?? is it now possible to use/go forth order logic. Canonnically, the 5th has to

1st order logic (lisp 1.5); 2nd order logic (scheme); 3rd order logic (emacs); ?? is it now possible to use/go forth order logic. Canonnically, the 5th has to happen after the forth.