I wonder why

"The most striking difference in reading occurs in Dream 25, in which Myōe meets Kujō Michiie and has a funny feeling about him which prompts him to ask, "Are you a deity?" Michiie in MSS (vol. 2, p. 127) replies, "Yes." But to the same question in the DNS version (p. 667), Michiie replies, "I am a cow." With rare exception, the readings of MSS have been followed."
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("Myōe the Dreamkeeper: ...", G.J. Tanabe, Jr)
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