(defun recursive-commutation (path-list)
  "Perform recursive commutation on a list"
  (flet ((apply-recursive-commutation (path)
	   (let* ((prefix-form (prefix-form path))
		  (operator (list (operator prefix-form)))
		  (second-path (inherited-path (operand-1 prefix-form) path))
		  (third-path (inherited-path (operand-2 prefix-form) path))
		  (operand-combinations (safe-path-product (recursive-commutation second-path)
							   (recursive-commutation third-path))))
	     (loop for operand-combination in operand-combinations
		append (commutation (appended-path operator operand-combination path))))))
    (typecase path-list
      (list (loop for path in path-list
	       append (apply-recursive-commutation path)))
      (atom (if (listp (prefix-form path-list))
		(apply-recursive-commutation path-list)
		(inherited-path prefix-form path-list))))))