I'm reading Each Moment is the Universe: Zen and the Way of Being Time by Katagiri Roshi, and I'm very interested in this passage (20-1 in my edition) about "kiya":

[Dogen] said if you want to say something about what a moment is, say that moment is arising. In Japnese the word for arising is ki. ... So, to explain moment, we can say just arising or arising only. Dogen said it is kiya. Dogen's use of ya, a strong affirmative, implies that he understood moment in a dynamic, nonconceptual sense. It is difficult to understand, but according to Dogen, arising appears as beings, the human world of existence. ...

Buddhism doesn't see the self [as an object], because when I am present in the domain of impermanence, I can't say who I am. I realize from the bottom of my mind that I exist, but I can't say anything at all about myself because there is no concept there. At that time I am just arising [kiya].
This sense of arising (in/as the moment) appearing as being (in/as the moment) is very powerful to me; Katagiri Roshi's passage is one of those that made me sit up in recognition of something I couldn't articulate before reading it -- even as it sits just beyond conception. And it made me wonder what else I might learn about kiya from you all.