According to one estimate, Ryotaku MAENO refused to put his name in "Kaitai Shinsho" because he had once promised not to study for his own name when he prayed for accomplishment of his school work at Tenman-gu Shrine on his way to Nagasaki for study.
一説には、良沢が長崎留学の途中で天満宮に学業成就を祈ったとき、自分の名前を上げるために勉学するのではないと約束したので名前を出すのを断ったという。