[ 14 ] this system of composition , in which the manipulation of tiny linguistic elements seems to form larger themes in a very organic way , is similar to the operation of the traditional oral singer , as described by milman parry : his major theme can be made up only of minor themes , his minor , only of lesser , and his lesser , only of the verses and phrases which he has heard from other singers ( the making of homeric verse : the collected papers of milman parry ( oxford : clarendon press , 1971 ) , 450 ) .