public function admin_proceed($action, $id)
 {
     switch ($action) {
         case 'add':
             $ontology = new ontology();
             print $ontology->get_form();
             break;
         case 'edit':
             print $this->ontologies[$id]->get_form();
             break;
         case "delete":
             if (is_object($this->ontologies[$id])) {
                 if ($this->ontologies[$id]->delete()) {
                     unset($this->ontologies[$id]);
                 } else {
                     //loupé
                 }
             }
             print $this->get_list();
             break;
         case 'save':
             if (!$this->ontologies[$id]) {
                 $ontology = new ontology($id);
                 $ontology->get_values_from_form();
                 $this->ontologies[$ontology->save()] = $ontology;
             } else {
                 $this->ontologies[$id]->get_values_from_form();
                 $this->ontologies[$id]->save();
             }
         default:
             print $this->get_list();
             break;
     }
 }