Soyo ya soyo nado te yamabe o mizariken kesa wa kuyuredo nan no kai nashi - Izumi Shikibu Nikki(English Translation & Meaning)

そよやそよなとて山へをみさり劔
けさは悔れと何のかひなし

Roma-ji: Soyo ya soyo nado te yamabe o mizariken kesa wa kuyuredo nan no kai nashi
English Translation: Yes, yes, that is so;
why did we not go and see
the mountainside?
This morning I regret it so,
yet nothing can be done
Meaning: Yes, yes, just so. Why didn't we go to see the mountainside? This morning I regret it, but it is all to no avail.
Commentary: 32 The Promise to View Autumn Leaves

On the evening of their exchange on the frosty morning, the prince came and invited her: "How lovely the autumn leaves on the mountains must be now. Come, let us go and see them," and Izumi Shikibu replied, "That would be delightful." But when the day came, the prince sent word: "Today I must stay shut in for a day of abstinence, which is a great pity. Once it is over, without fail." That night the winter showers fell harder than usual, with a sound as though every leaf on the trees would be stripped away. Waking, Izumi Shikibu murmured to herself, "before the wind," and spent the rest of the night regretting that the leaves must all have fallen and wishing they had gone to see them the day before.
The woman is Izumi Shikibu, daughter of Ōe no Masamune and, as the wife of Tachibana no Michisada, Governor of Izumi, mother of Koshikibu no Naishi. The Prince of the Dazaifu is Prince Atsumichi, fourth son of Emperor Reizei, so called because he served as Governor-General of the Dazaifu. A day of abstinence was a period of staying shut indoors and keeping oneself pure in order to avoid misfortune, according to the art of yin and yang.
When Izumi Shikibu's "Momijiba wa yowa no shigure ni araji kashi kinō yamabe o mitaramashikaba" arrived, the prince read it and sent back this poem.
In the margin of this poem he added "Arashi to wa omou mono kara momijiba no chiri ya nokoreru isa tazune min."

The first line, "yes, yes," strongly agrees with her words. The second and third lines mean "why did we not see the mountainside?" taking up her "if only we had seen the mountainside" directly, with an auxiliary of past conjecture.
The lower verses mean "I regret it this morning, but it is of no avail," with an adversative particle. Frankly admitting his fault in postponing the promise for his abstinence, and joining her lament with regrets of his own, he takes her disappointment to heart.
Author: Prince Atsumichi
Source: Izumi Shikibu Nikki
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