Ika nareba onaji nagare no mizu ni shimo sa nomi wa tsuki no utsuru naruramu - Shika Wakashu(English Translation & Meaning)

いかなれば同じ流れの水にしも
さのみは月の映るなるらむ

Roma-ji: Ika nareba onaji nagare no mizu ni shimo sa nomi wa tsuki no utsuru naruramu
English Translation: Why should it be so,
that in water of the same
flowing stream as this,
the moon should be reflected
only there, and so brightly
Meaning: Why is it that in water of one and the same stream, the moon should be reflected so — only there?
Commentary: Book Nine Miscellaneous Poems I 321

The poet asks why, though the water flows in the same stream, the moon should be reflected so in one place. With no headnote the circumstances are unclear, but voicing doubt at the moon reflected differently in one and the same stream, the poem hints at feelings entrusted to some other matter.
Poem 290 of this book also sings of the moon reflected in water.

The first line, "ika nareba" (why is it), poses a question answering to "ramu" in the final line. Poem 299 of this book begins with the same line, also questioning the moon's behavior.
The second line, "onaji nagare no" (of the same stream), refers to one river's flow.
The third line, "mizu ni shimo," stresses with "shimo": though it is the same stream's water.
The fourth line, "sa nomi wa tsuki no," means "only so," limiting how the moon is reflected.
The final line, "utsuru naruramu," combines the copula "nari" and conjectural "ramu": why is it reflected so?
Source: Shika Wakashu
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