Kakaramu to kanete shiriseba Koshi no umi no ariso no nami mo misemashi mono o

かからむとかねて知りせば越の海の
荒磯の波も見せましものを

Roma-ji: Kakaramu to kanete shiriseba Koshi no umi no ariso no nami mo misemashi mono o
English Translation: Had I but known before
that it was to come to this,
the waves upon the rocks
of the sea of Koshi too
I would surely have shown you
Meaning: Had I only known beforehand that it would come to this, I would have shown you the waves breaking on the rocky shores of the sea of Koshi.
Commentary: Book Seventeen 3959

Headnote continued from the preceding poem: "Envoy to a poem, with tanka, lamenting my younger brother who has passed away for ever"
Had he known it would come to this, he would have shown his brother the waves on the rocky shores of the sea of Koshi—a poem of regret. This is an envoy to the chōka Yakamochi composed in Etchū on the twenty-fifth day of the ninth month of 746, on hearing from afar that his younger brother Fumimochi had died in the capital. The chōka tells how his brother saw him off as far as the riverbank of the Izumi when he went down to Etchū, where they parted saying "I shall return safe and sound," and how he was told that his brother, a lover of flowers and plants, had been cremated on Mount Saho and his smoke had trailed away as white clouds. Regretting that he could not show his flower-loving brother the beautiful seascapes of Etchū, he laments a death that cannot be undone.
The poet, Ōtomo no Yakamochi, was the son of the Major Counselor Ōtomo no Tabito. Appointed Governor of Etchū in 746, he spent five years there, later serving as Junior Counselor and Governor of Inaba before rising to Middle Counselor. He is thought to have played a central role in compiling the Man'yōshū.
The left note reads, "The above was composed on the twenty-fifth day of the ninth month, autumn, of the eighteenth year of Tenpyō, by Ōtomo no Sukune Yakamochi, Governor of Etchū, grieving on hearing from afar of his younger brother's death."

First line, "kakaramu to": "that it would be thus," meaning his brother's death.
Second line, "kanete shiriseba": seba is the irrealis of the past ki with ba, answering mashi in the last line to express a counterfactual—"had I known beforehand."
Third line, "Koshi no umi no": the sea of Etchū.
Fourth line, "ariso no nami mo": ariso is a rough, rocky shore. The Etchū seascape to which Yakamochi invited his banquet companions in 3954, "to see the waves rolling in," here becomes what he wished to show his dead brother.
Fifth line, "misemashi mono o": "I would have shown you," mashi expressing a counterfactual and mono o an adversative lament.
Author: Otomo no Yakamochi
Source: Manyoshu
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