Here is a poem:

Silvery moon rides high in the sky
I ride a tiny boat in the vast and misty sea.
Moon and sea forgotten
I forget that I have forgotten
And before the window
I sit quietly in meditation until midnight.
—Jakushitsu (1290-1367)

I forget that I have forgotten! Jakushitsu lived about a century after Dogen, so it is possible he read Dogen’s Genjokoan (To study the self is to forget the self; to forget the self is to be enlightened by all things…) but probably not since he was a Rinzai Zen teacher. He lived many years as a hermit and only began to teach Zen to others late in his life.

But the human mind can be hard to live with; hard to deal with. Our nervous systems are sensitive, undoubtedly too sensitive for our own happiness, very often. Someone once described human emotions as “hair-trigger,” and our entire thinking/emotional system is such a complex unpredictable sensitive and “nervous” system that it can be the cause of a great deal of difficulty. Therefore practice.

What is practice? –this is a question I carried for a number of years. Zen practice is formal meditation, daily-life awareness of one’s ongoing mental state (called “mindfulness”), and specific practices to shape our minds and thinking processes in the direction of wholesomeness and well-being: compassion, generosity, equanimity, kindness, acceptance, and so on.