Can the "Senika heresy" be useful?

Question

The Rhetoric of Immediacy: A Cultural Critique of Chan/Zen Buddhism By Bernard Faure p60 (I've not read this book) links it to linji ("the true man without affairs")

Wiki says

In his later years Dōgen often severely criticized the Senika heresy (sennigedo), which is the erroneous view that the mind abides while the form perishes. According to this view, there is a bright spiritual intelligence contained in our body that is the source of self-understanding. When the body dies, the spiritual intelligence alone does not perish but abides immutably. This view, Dōgen argues, when "hearing of the doctrine of this very mind (itself is buddha), takes it to mean that the discriminating knowledge of sentient beings is itself the buddha"

Dōgen (c. 1230-50) as cited in Masao Abe, Steven Heine (1992) A Study of Dōgen: His Philosophy and Religion. p. 158
The Senika heresy here mentioned is a Buddhist believe in eternalism of the self.

I'm interested, then, in whether it's only really a heresy in Soto Buddhism, and other traditions might find it useful.

I think it may be a useful fiction, which is why I ask.

Answer 1

What Dōgen calls sennigedo is a view found in several schools of Buddhism, for example in the teachings of Tendai contemporary with Dōgen in Japan. But this is not what Matsuo Basho was expressing in "Mind itself is Buddha", the poem Dōgen used to argue the criticism you expressed in your quote. He quotes this poem in the story of Damei Fachang (Daibai Hojo) in both his Shobogenzo and Eiheikoroku. What he actually argues is:

“The mind that has been authentically transmitted is ‘one mind is all dharmas; all dharmas are one mind.’….. We clearly understand that the mind refers to the mountains, rivers, and the great earth; the sun, the moon and the stars. …. Therefore, ‘mind itself is buddha’ refers to all the buddhas who carry out arousing bodhi-mind, practice, awakening, and nirvana. Those who have not yet been carrying out arousing bodhi-mind, practice, awakening and nirvana are not ‘mind itself is buddha.'”

Stated differently, Dōgen argues that until you realize (in both senses of the English word simultaneously, not just intellectually) that "Mind is Buddha", you risk to conceptualize Buddha-nature as eternal & transcendent of causation and death. He is therefore not criticizing Basho, but the concept underlying the interpretation that all factors of experience (hō in Japanese, Dharmas in Sanskrit) are somehow not subject to causation (which implies they are timeless).

The best elaboration on this argument I know is in Heine's Existential and Ontological Dimensions of Time in Heidegger and Dogen Chapter "The Question of Time"

Answer 2

The idea that the Buddha is "unaffected by the vicissitudes of bodily existence" [Mystical Realist, Kim] seems to be the root mistake that Dogen is proselytizing against.

What may be key to interpreting it is that all post Madhyamaka Buddhists taught that form, which is what the body is, is mind. Dogen then could be emphasizing that rebirth, in this life and the next, and Buddhahood, makes for some new body by mental causation. Not, then, than mind perishes completely with this body.

I've done very little koan or Rinzai study, but would guess that our original enlightenment, as the body of the Buddha, is emphasized therein: because Soto, compared to "the true man without affairs", is less concerned with 'words' and 'discriminative thought', 'causation'.