Mizu no omo ni teru tsukinami o kazoureba koyoi zo aki no monaka narikeru - Shui Wakashu(English Translation & Meaning)

水の面に照る月なみを数ふれば
今宵ぞ秋の最中なりける

Roma-ji: Mizu no omo ni teru tsukinami o kazoureba koyoi zo aki no monaka narikeru
English Translation: On the water's face
counting up the moonlit waves,
the months as they pass,
I find this night is the heart,
the very midst of autumn.
Meaning: Counting the months as I watch the moonlit waves shining on the water, I find that tonight is the very middle of autumn.
Commentary: Book Three Autumn Poems 171

Headnote: "For a folding screen, at a scene of people at leisure at a house with a pond on the fifteenth night of the Eighth Month"
Watching the waves of moonlight shining on the pond and counting the months, the poet realizes that tonight, the fifteenth night of the Eighth Month, is the very middle of autumn. With "tsukinami" meaning both the count of months and moonlit waves, it is a celebrated poem that wittily captures the harvest moon of mid-autumn. According to the headnote, it accompanied a scene on a folding screen of people at leisure at a house with a pond on the fifteenth night of the Eighth Month.
The author, written as Minamoto no Shitagau, is Minamoto no Shitagō. Of the Saga Genji line, he was a scholar and poet of the mid-Heian period. As one of the Five Men of the Pear Chamber he took part in compiling the Gosenshū, and he compiled the dictionary Wamyō Ruijushō. He is counted among the Thirty-Six Immortal Poets.

First line, "mizu no omo ni," means "on the surface of the water." Poems on the moon follow from here, and this poem begins the sequence.
Second line, "teru tsukinami o," is a pivot word in which "tsukinami" means both the count of months and the waves lit by the moon.
Third line, "kazoureba," means "when I count," with "ba" marking an established condition. Of the autumn months, the Seventh, Eighth and Ninth, the fifteenth of the Eighth Month falls exactly in the middle.
Fourth line, "koyoi zo aki no," means "tonight is autumn's," with the emphatic particle "zo," which is resolved by "keru" in the final line.
Final line, "monaka narikeru," means "was its very middle," with "keru" expressing the exclamation of realization. It pinpoints by counting the fifteenth night of the Eighth Month as the exact middle of the three months of autumn.
Author: Minamoto no Shitagō
Source: Shui Wakashu
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