‘Buddhas are those who have comprehended and completed things in the realm of sentient beings; sentient beings are those who have not yet comprehended and completed things in the realm of buddhas. If you want to attain Oneness, just give up both buddhas and sentient beings at once: then there is no “comprehended and completed” or “not comprehended and completed.” (Swampland Flowers)

If you detect echoes of the opening paragraphs of the Genjo Koan, you would not be alone. I am not enough of a scholar to know for sure whether Dogen would have read Tahui, but I think he made no pretence at being entirely original in his writing, and was mainly concerned with transmitting correct understanding, which he did sometimes grudgingly admit to finding in the words of his Chinese predecessors.