In the Nijo school, a secret theory regarding explication of waka contained in "Kokin Wakashu" that has been considered to be the ideal of Chokusen wakashu has been secretly inherited from the master to the disciple as 'Kokin denju.'
二条派には勅撰和歌集の理想とされてきた『古今和歌集』所収和歌の解釈に関する秘説が「古今伝授」として師から弟子に秘かに継承されてきた。