classic waka stream

棹させど深さも知らぬふちなれば
色をば人も知らじとぞ思ふ
Roma-ji

Sao sasedo fukasa mo shiranu fuchi nareba iro o ba hito mo shiraji to zo omou

English Translation
Though one plies a pole,
its depth can never be known,
this pool of wisteria;
its color too, I believe,
no one could ever know
Meaning
Since this wisteria is a deep pool whose bottom no pole can reach, I think no one could ever fathom the depth of its color.
Commentary
Book Three Spring Poems III 127

Headnote continued from the preceding poem: "Around the last ten days of the Third Month, when the Sanjō Minister of the Right had gone to the house of Lord Kanesuke, and by the garden stream where the wisteria was in bloom, various people were drinking wine."
Since the wisteria is like a pool whose depth no pole can sound, the poet says, no one can know the full depth of its color. Taking up the "depth" of the two preceding poems, he praises the wisteria, and seems also to praise the depth of feeling of host and guest.
The three poems from 125 to this one form a sequence exchanged at a wisteria banquet at Fujiwara no Kanesuke's house, in which guest, host and Tsurayuki each sang of the depth of the wisteria's color.
The poet, Ki no Tsurayuki, was a son of Ki no Mochiyuki. He was the leading compiler of the Kokin Wakashū and wrote its kana preface. He served as governor of Tosa among other posts, is known as the author of the Tosa Diary, and is counted among the Thirty-Six Immortal Poets.

In the first line, "sao sasu" means to thrust a pole into the riverbed to move a boat, and "do" is adversative. As an associated word for "pool," it leads to the third line.
The second line, "fukasa mo shiranu," takes up "iro no fukasa" and "iro fukaku" of the two preceding poems, showing an unfathomable depth.
In the third line, "fuchi" is a pivot word joining "wisteria" and "deep pool," the same conceit as "na ni ou fuchi" in 125.
In the fourth line, "o ba" is emphatic, pointing to the depth of the wisteria's color.
In the last line, "ji" is negative conjecture, and "zo" forms a kakarimusubi pattern with the attributive "omou": "I think no one could know it."
Author
Ki no Tsurayuki
Source
Gosen Wakashu
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