(defun write-inferred-superclasses (source-filename dest-filename inferred-ontology-uri)
  (let ((kb (load-kb-jena source-filename)))
    (if (check kb)
	(with-ontology inferred (:base inferred-ontology-uri) 
	    ((loop for (sub super) in
		  (set-difference (loop for class in (descendants !owl:Thing kb)
				     append
				     (loop for super in (parents class kb)
					collect (list class super)))
				  (sparql '(:select (?sub ?super) (:distinct t) (?sub !rdfs:subClassOf ?super)) :use-reasoner :jena :kb kb)
				  :test 'equal)
		collect
		  (class sub :partial super)))
	  (write-rdfxml inferred dest-filename))
	(error "KB isn't consistent, so inferred superclasses won't be correct"))))