In truth however, it is uncertain whether or not this anecdote is based in historical fact; it had spread in the mid part of the Edo period in Joruri (a narration accompanying the Japanese traditional puppet play) called "Ono Tofu's Green Willow and Ink Stone," which was first staged in 1754.
ただし、この逸話は史実かどうか不明で、広まったのは江戸時代中期の浄瑠璃『小野道風青柳硯（おののどうふうあおやぎすずり）』（初演1754年（宝暦4年））からと見られる。