The last sentence of Dogen’s Fukanzazengi, his universal recommendation of Zazen is, “The treasure house will open by itself and you may use it freely.”
The meaning of his masterwork Shobogenzo is The Treasury (Zo) of the True Dharma Eye.
When we hear treasury we may well think of it as being a piece of poetic ornamentation that we can safely disregard.
We can’t, because it’s the key to illuminating a neglected major influence on Zen— Yogacara. We think of ourselves as descending simply from Nagarjuna and the emptiness teachings, but it’s not true.
When the Chinese were looking for a suitable word for tathagatagarbha, which can mean Buddha embryo or Buddha womb, the word they chose was Zong.
Zong variously means treasure house—womb—depository—storehouse. ‘Zo’ is the Japanese translation of ‘Zong’. This decisively shifted the idea of Buddha Nature from something that will happen to something present now. The argument which then took place within Chinese Buddhism was whether all beings or only some beings had this—the universal view eventually winning out.
And when the Chinese came to render alaya consciousness, storehouse consciousness
(the 8th and foundational consciousness in the Yogacara system) they used the same word—Zong.
In this way, two ideas which were distinct, Alaya consciousness and inherent Buddha Nature, came to be closely linked. The identity of the two seems to have originated in the Lankavatara Sutra, which was Indian, but which was brought to China – symbolically, one imagines – by Bodhidharma, the first Zen Patriarch.
Yogacara as a school didn’t prosper in China, perhaps because of its denial of universal Buddha nature, and although it remained a major strand of Zen, its influence was concealed in Zen mythology by the Sixth Patriarch’s emphasis on The Diamond Sutra (one of the prajnaparamita sutras) rather than The Lankavatara Sutra. The creators of the Platform Sutra, our source for ‘information’ about him, were almost certainly adherents of the Oxhead School, the Zen School which cleaved most closely to Nagarjuna.
Once uncovered, you can see Yogacara’s influence everywhere. For example, there is a very close affinity between Dogen’s Kuge and the ‘three natures’ set out in the Samdhinirmocana Sutra, the primary Yogacara Sutra, as well as the simile of ‘Sky Flowers’ which appears in that sutra.
It’s hard to see at first, because Zen language is poetical, vigorous and everyday whereas Yogacara is academic and hairsplitting, but it’s clearly there.
Arguably Yogacara is a major component of Zen, but Zogacara in a Chinese sense, one perhaps Indian Buddhists wouldn’t recognize , and which modern Zen has actively concealed, perhaps because of a misunderstanding about Yogacara.
That misunderstanding is to see Yogacara as Idealistic rather than Phenomenological. If we see it making statements about the nature of our experience, rather than the nature of reality, then we can see it as the logical development of Nagarjuna, not as some embarrassing Indian exoticism which denies the reality of anything other than the mind. It is the other side of Emptiness, as it were, considering it from the subjective side, rather than the objective side of Nagarjuna.