Yamato poems take human hearts as their seeds, and become ten thousand words. People in the world encounter many things, so they entrust what they think in their hearts to what they see and hear and send forth speech. When we hear the warblers chirping in the flowers and the voices of the frogs who live in the water, what among living things does not compose poetry? What can move the heavens without expending strength, make unseen gods and demons feel pathos, soften the relations between men and women, and soothe the hearts of fierce warriors, is poetry.
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Yamato poems
The word uta that is used here as "poem" has a broader meaning, one that encompasses folk songs and other chants as well as poetry (whether chanted, sung, or read silently or out loud). I have used the term "poem" rather than "song" in the translation, but it should be remembered that any use of this term "poem" may also have the suggestion of a song or chant as well, and does not always necessarily refer solely to a waka poem. This is the only use of Yamatouta ("Yamato poem") in the KKS, but uses in other sources show that it generally indicates a Japanese poem in contrast to a Chinese one. Yamato is the name of a province or area of Japan, but it also used more broadly to refer to Japan as a whole.
Ten thousand words
That is, "many/various words."
many things
koto waza -- this seems to broadly refer to anything humans do or experience in their daily lives.
warbler
The uguisu, a common early spring image. A crying warbler. Courtesy of Wikipedia
fierce warriors
In the Heian period the word mononofu usually indicates not just a warrior, but one who is too rough and uncultured to understand the finer aesthetics of the court culture. In other words, poems can reach even people who have no understanding of their proper aesthetic.
frog
Because the warbler is a spring image, many commentaries have suggested that this is an autumn "kajika frog," but as Takeoka and Katagiri both show through exhaustive examples, the term kawazu is just a poetic word for "frog" and refers to normal spring frogs. Thus this is not a paired spring-autumn image, but just two spring images used to stand in for all animals. File:File:Pelophylax bedriagae - Levant water frog 01.jpgA frog.
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The first section of the preface presents a broad description of the nature of poetry. Parallels for the expression can be found in the 5th century The Literary Mind and the Carving of Dragons as well as the preface and classical commentaries to the Classic of Poetry.
In particular, the so-called "Great Preface" to the Classic of Poetry reads:
Poetry is the product of earnest thought. Thought [cherished] in the mind becomes earnest; exhibited in words, it becomes poetry...therefore, correctly to set forth the successes and failures [of government], to move Heaven and Earth, and to excite spiritual Beings to action, there is no readier instrument than poetry.
- trans. James Legge , Classic of Poetry, preface
The commentaries to the Classic expand on this, but Katagiri holds that Tsurayuki's expression of the thought is clearer.
Medieval commentaries contained a number of specific examples to explain the references in the second part of the paragraph. Several works contain legends involving frogs and birds actually composing 31-syllable poems, although these are roundly condemned starting in the 15th century and have no identifiable sources outside of these commentaries. More long lasting are poems that supposedly brought rain or brought a horse back to health -- these poems are found in actual sources but the legends are later inventions. See Katagiri v1 p 101, ff. for details. Although the legends have no real basis or applicability to Tsurayuki's poetics, they exerted a large amount of influence in the Kamakura and Muromachi periods.