It is not always common knowledge in pop Zen that the shift from Indian Buddhism to the many forms of Chinese Buddhism occurred in the T’ang Dynasty (618 – 907 AD). Traditions such as T’ien-t’ai, Hua-yen, Pure Land, and Ch’an (Zen) arose during the T’ang despite a period of religious persecution.

Many of the T’ang Buddhist schools developed around a particular Sutra such as the Lotus Sutra or the Avatamsaka Sutra. Supposedly, Ch’an developed around the idea of transmitting the Buddha’s awakening, directly. This transmission was a Mind to Mind transmission which went beyond the Sutras, not to mention words and letters. This is the same as saying the moon in the sky is beyond the finger pointing including the word, “moon” and its letters. Indeed, what the Buddha realized was truly transcendent.

The most prominent Ch’an school of the T’ang was known as the “The East Mountain Dharma Gate” (Tung-shan Fa-men) owing to the previous efforts of Tao-hsin (580–651) and Hung-jen (601–674), both of whom were considered to be Patriarchs . While it might be correct to call East Mountain a “Zen school” the name “Zen school” has never been used as the name of a particular school. The popularity of East Mountain was a watershed moment for the development of future Zen Buddhism.

Before East Mountain was a small school in the Liang Dynasty known as the Lanka School because it used the Lankavatara Sutra as a means of transmission. The Lanka School was likely initiated by either Gunabhadra or Bodhidharma. Its teachers were called “Lanka masters.” They shook off the ways of the world (dhûta) using only one robe and one bowl. This school had very little if any popular appeal because of the severity of its practices and the difficulty of understanding the Lankavatara Sutra. Thanks to East Mountain’s efforts to link itself with the Lanka School, the popularity of Zen Buddhism grew.

What is remarkable about Zen Buddhism is that there is an unbroken golden thread which runs through its various traditions. This gold thread is Buddha Mind or in the words of the Third Patriarch Seng-ts’an, “One Reality” which is the true essence or substance of the profuse diversity of our phenomenal world. According to Seng-ts-an,

It is like water making waves, like gold making vessels. The gold is the substance of the vessel, so no vessel is not gold. The waves are the functioning of the water, so no waves are different from the water” (Cleary, Zen Dawn, 45).

By realizing this One Reality we cannot help but see that our phenomenal world is a spectacular illusion—like a mirage—that depends upon the One Reality. Getting us to this awakening is the task of Zen Buddhism.