Teru tsuki no iwama no mizu ni yadorazu wa tama iru kazu o ikade shiramashi - Kinyo Wakashu(English Translation & Meaning)

照る月の岩間の水に宿らずは
玉ゐる数をいかで知らまし

Roma-ji: Teru tsuki no iwama no mizu ni yadorazu wa tama iru kazu o ikade shiramashi
English Translation: If the shining moon
had not lodged its light within
the water among rocks,
how could I have come to know
the number of its jewels
Meaning: Had the shining moon not been reflected in the water among the rocks, how could I ever have counted the jewel-like drops gathered there?
Commentary: Book Three Autumn Poems 181

It is because the shining moon is reflected in the water flowing among the rocks that even the number of jewel-like drops can be seen. The poem catches, through a contrary-to-fact supposition, the sparkle of tiny drops lit by the moon.
Its opening, 'the shining moon', is the same as the opening of poem 193 in this book.
From poem 174 through poem 217 in this book a long sequence of moon poems follows, from the evening moon through the bright moon of the fifteenth night of the Eighth Month to the moon at dawn, singing of the moon in all its aspects and of the heart that gazes on it.
The author, Tsunenobu, is Minamoto no Tsunenobu. A son of Minamoto no Michikata, he rose to Major Counselor and was called the Katsura Counselor. In his last years he died at his post as Provisional Governor-General of Dazaifu. He was the father of the compiler, Minamoto no Toshiyori.

First line, 'teru tsuki no', means the brightly shining moon. Poem 193 in this book opens with the same line.
Second line, 'iwama no mizu ni', means in the water among the rocks.
Third line, 'yadorazu wa', means if it had not been reflected, zu wa expressing a negative supposition answered by mashi in the final line.
Fourth line, 'tama iru kazu o', uses tama, jewels, for drops and spray, and iru, lying there.
Final line, 'ikade shiramashi', means how could I have known, closing with the contrary-to-fact mashi.
Author: Minamoto no Tsunenobu
Source: Kinyo Wakashu
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