What is it that is not a companion to all dharmas?

The layman Pang Yun asked the Chan master Mazu Daoyi: "Who is the one who keeps no companion among the myriad dharmas?" The master said: "When you can swallow all the water of the West River in one gulp, then I will tell you." Upon hearing this, Pang Yun was enlightened. What did he awaken to? He awakened to this "not-a-thing" that keeps no companion among the myriad dharmas. What kind of thing is it? Why does it keep no companion among the myriad dharmas?

What the layman Pang Yun awakened to was the mind of self-nature purity (prakṛti-viśuddha). This mind keeps no companion among the myriad dharmas, because the tathāgatagarbha has no form, so it keeps no companion with form; it has no sound, so it keeps no companion with sounds; it has no smell, so it keeps no companion with the object-realm of smells; it has no taste, so it keeps no companion with the object-realm of tastes; it has no touch, so it keeps no companion with the object-realm of touch; it has no dharmas, so it keeps no companion with the object-realm of mental objects. The tathāgatagarbha has no six faculties, so it keeps no companion with the six faculties; it has no six consciousnesses, so it keeps no companion with the six consciousnesses. The tathāgatagarbha has no Four Noble Truths, so it keeps no companion with the dharma of the Four Noble Truths; it has no bodhisattva's six perfections, so it keeps no companion with the six perfections; the tathāgatagarbha has no twelve links of dependent origination, so it keeps no companion with the dharma of the twelve links of dependent origination; the tathāgatagarbha has no worldly dharmas, so it keeps no companion with any worldly dharma. When the entire world ceases, He does not cease; therefore the tathāgatagarbha is precisely the mind that keeps no companion among the myriad dharmas.

Furthermore, because He does not mix together with the myriad dharmas—this is what the Āgama sūtras call "not being contained within"—the five aggregates and eighteen realms are not within the tathāgatagarbha, and the tathāgatagarbha is not within the five aggregates and eighteen realms; the two are not of the same kind, do not mix together, are not one thing, are not the same thing, and therefore cannot be mixed. When the five aggregates perish, the tathāgatagarbha does not perish; He can exist independently by Himself, existing without depending on any dharma whatsoever—thus He keeps no companion among the myriad dharmas.

Chan master Mazu instructed the layman Pang Yun: "When you swallow all the water of the West River in one gulp, then I will tell you." In fact, this had already been spoken—it is just that it is not something knowable through the deliberation, imagination, and inference of ordinary people's mind consciousness. Pang Yun was also a sharp-witted fellow; at that moment he knew that that One would manifest and reveal Himself—his wisdom was extraordinary. It is not like what we people nowadays think: that one simply cannot drink the water of the West River, let alone drink it dry, and so one lets go of it—and letting go is enlightenment. Or one thinks that the water of the West River is also manifested by my own mind and is therefore emptiness (śūnyatā), and that understanding this principle is enlightenment. To understand it this way is a mistake; one cannot awaken to the tathāgatagarbha mind-substance, and even less does one know how the tathāgatagarbha produces the five aggregates and the myriad dharmas.

Now, we too drink water every day, yet we all treat it as an ordinary matter and let it slip past us, never knowing that there is a mystery hidden here—this is called "using it daily yet not knowing it." Chan master Zhaozhou used to tell those who came to visit him: "Go have some tea." The words of great Chan masters always carry a special intent, a deliberate purpose; alas, ordinary people do not understand their meaning and drink tea once after another entirely in vain, gaining nothing in the end. We should, while drinking tea, ask ourselves: Who is drinking the tea? What is the principle behind drinking tea? If we do this, sooner or later one day we will be able to awaken to the secret within.