Hisakata no tsuki no hikari shi kiyokereba aki no nakaba o sora ni shiru kana

久方の月の光し清ければ
秋のなかばを空に知るかな

Roma-ji: Hisakata no tsuki no hikari shi kiyokereba aki no nakaba o sora ni shiru kana
English Translation: The far-shining moon,
since its light is all so clear,
tells me from the sky
that we stand at autumn's heart—
so the heavens let me know.
Meaning: Because the light of the moon is so especially clear, I know from the sky that it is the very middle of autumn.
Commentary: Autumn Poems 286

Headnote: "On the spirit of the fifteenth night of the eighth month"
Because the moonlight on the fifteenth night of the eighth month is so especially clear, the poet looks up at the sky and knows that autumn is exactly at its midpoint. He senses the harvest moon not by the calendar but by the very clarity of its light.
The Ruijū text gives the headnote as "The fifteenth night of the eighth month."

Line 1, hisakata no, is a pillow word for "moon."
Line 2: shi is an emphatic particle, "the moonlight indeed."
Line 3: ba after the evaluative form marks a cause, "since it is clear."
Line 4, "the middle of autumn," refers to the fifteenth day of the eighth month.
Line 5: kana is an exclamatory final particle, "so I know from the sky." Following the moons of famous places, this poem sings of the most renowned moon of the calendar, the mid-autumn moon.
Author: Minamoto no Sanetomo
Source: Kinkaishu
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