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Ton'a

, also spelled as Tonna; lay name – Nikaidō Sadamune 二階堂貞宗. A Japanese Buddhist poet, student of Nijō Tameyo 二条為世. Ton'a took a tonsure at Enryaku-ji Temple, but was later associated with the Ji sect 時宗 (founded by Ippen). He looked up to Saigyō's poetic genius. Here are two of his most well-known poems:

naku semi no koe mo hitotsu ni hibikite matsu kage suzushi yama no takitsuse

Crying cicadas are in one voice with the sound that reverberates – cool, in the shade of the pines – from a mountain cascade.

ne ni tatete nageku wa nani zo utsusemi no munashiki yo to wa shiranu mono ka wa

Just what can it be that makes them cry so loudly? But, ah, of course: cicadas would know how empty is this world of the cicada shell.