Japanese verse has the human heart as its seed, and it's the countless leaves of words that it has, in fact, become.  It's that, people in the world, as their affairs and doings are many and varied, have attached what they feel in their hearts to the things they see and hear.  When we've heard the voices of the warbler that sings among the blossoms and the frogs that dwell in the waters, of all things alive and living-- 

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