The Mahāparinirvāṇa Sūtra states, “ ‘All existences’ without exception possess the Buddha nature” (issai shujō kotogoloku busshō o yūsu). However, in the Busshō (Buddha Nature) chapter of the Shabōgenzō, Dōgen reinterprets the Chinese in an ingenious manner to read, “All existences are the Buddha nature” (issai shujō shitsu u busshō). In this way he rejected the view, held, for example, by the Consciousness-Only school, that the Buddha nature is a “seed” or psychic potential that evolves in a linear fashion from latency to realization, and instead identifies it with the unchanging, ultimate truth, designated as Suchness (Skt. tathatā, Jap. shinnyo), Emptiness (Śūnyatā, kū), or the Dharma nature (dharmatā, hosshō). This Buddha nature, being identified with “all existences,” exists nowhere apart from the destruction and coming-into-being of the phenomenal world in the present moment, or absolute now.

Because this “now” is absolute, and because “there is no time that has not arrived,” Buddhahood is not a potential that will unfold in the future, but can be realized only in the present moment. In other words, attaining Buddhahood is not, in Dōgen’s view, a gradual evolving from potential to realization associated with a linear view of time. In this way, he was able to resolve the contradiction that had originally puzzled him. “The Buddha nature and becoming a Buddha always occur simultaneously, he concluded. This view wipes out at a single stroke any metaphysical gap between practice and enlightenment: Whenever one sits in meditation, he simultaneously enters the realm of Buddha. Dōgen called this the “kōan realized in reality,” or genjō kōan.

Viewing time and enlightenment in this way, Dōgen found himself unable to accept the historical view of three-period thought, according to which the Dharma becomes obscured with the passage of time. “Time does not pass,” he believed, and the Dharma does not decline; wherever one sits in meditation, he is contemporaneous with Buddha.