In these writings, emptiness is not treated as a cold negation but as the very dynamism of phenomena themselves. Rather than a static void, emptiness appears as the ceaseless arising and passing of things, each event complete in its own “being‑time,” lacking any fixed essence yet fully itself. The emptiness of self is expressed as the study and forgetting of the self, where no substantial subject can be found apart from the flow of conditions. This is not a denial of the world but its true mode of existence: mountains, rivers, doors, tiles, and bowls show their suchness precisely as empty, impermanent, and dependently arisen. Emptiness thus becomes the living field in which practice unfolds, the texture of immediate experience rather than a distant metaphysical claim.

Nonduality, in turn, is presented as the collapse of all hard oppositions that ordinarily structure experience. Delusion and enlightenment, life and death, buddhas and sentient beings are shown as neither simply one nor two, revealing that the apparent gap between them is a provisional standpoint. Practice and realization are said to be one, so that seated meditation is not a technique aimed at a future goal but the present activity of enlightenment itself. The expression “dropping off body and mind” points to the release of the subject–object split, where body and mind are no longer grasped as separate substances. Even the environment is drawn into this nondual vision: mountains and waters are said to practice and realize the Dharma, so that there is no isolated observer standing over against a mute nature.

Within this vision, Buddha‑nature is affirmed yet freed from the notion of a hidden, unchanging essence. All beings are said not only to have Buddha‑nature but to be Buddha‑nature, and this Buddha‑nature is identified with impermanence and with the very functioning of “being‑time.” It is described as dynamic activity rather than a static core, so that the flux and emptiness of things is precisely their Buddhahood. Zazen, ethical conduct, and everyday activity are not means to uncover a buried treasure but the direct manifestation of Buddha‑nature as it unfolds moment by moment. The whole universe, including what is usually called insentient nature, expresses this Buddha‑nature, eroding the boundary between sentient and non‑sentient beings.

Taken together, these strands form a single tapestry rather than three separate doctrines. Because all things are empty, no independent self stands apart from the world, and this very lack of separation is nonduality. Because there is no gap between samsara and nirvana, practice in this body‑mind and world is already the work of a Buddha. And because Buddha‑nature is nothing other than the impermanent, empty activity of each moment, enlightenment is not an escape from this life but complete intimacy with things as they are.