on those rare occasions when someone would treat his dedication to proper behavior with levity , saying for instance that such enslavement to mere forms was inane and pointless , l. dudley fitzgibbon would peer over his black rimmed glasses perched on his aquiline anglo-norman nose and smile good-humoredly ( for that too was the mark of a gentleman ) while explaining that in his considered judgment the rules of etiquette and proper behavior , far from being useless and inane , were what separated us from the beasts .