He preached Buddhism at the Imperial court, and was noted for his poetry in the Literature of the Five Mountains (Gozan bungaku) tradition.

He was the compiler of a thirty-chapter Buddhist history, the Genko Shakusho, the oldest extant account of Buddhism in Japan.

Kokan was the son of an officer of the palace guard and a mother of the aristocratic Minamoto clan.

At age ten he was ordained there, but later began study with the Zen master Kian at the Nanzenji monastery.

At the end of his life, the emperor Gomurakami conferred upon him the title kokushi or National Teacher.

Kokan is noted for writing the Genko Shakusho, the oldest extant account of Buddhism in Japan.

In the introduction to the work, Kokan wrote that he was shamed into writing it after the Chinese monk Yishan Yining expressed his surprise that no such history existed in Japan.

Kokan Shiren's deceptively simple and straightforward narration gave an early voice to what would become a profound cultural transformation in Japan: What I liked to do for fun when I was a child was to gather up sacks of stones and pile them on a table near the window high and free.

When I reached middle age, I felt ashamed of doing this and so I stopped, becoming like any other ordinary person, obtuse like a brick.

A visitor saw it and exclaimed, “Okay, okay, but it seems a little bald, doesn’t it?” I responded, “You see a pile of stones and fail to see the mountains.

Of course you will discover the utter vexation of your creations withering and wilting due to carelessness of slow watering and tending.

For two days I passed through areas of great trees and forests, but on the third morning there wasn’t a blade of grass to be seen!

“These stones then, just a number of inches tall, and this tray roughly a foot across, they are nothing short of a mountainous island rising from the sea!

“So is it not fitting that I guard against weeds, carefully watching and laboring over the thing, taking delight in its total subtlety?

The alternations of plant life, their blooming in the morning and fading in the evening, are the splendor of the four seasons with their countless transformations and myriad changes!

Why, there is a vast plain on a fly’s eyelash and whole nations in a snail’s horn, a Chinese philosopher has told us.