Seon meditation’s goal is to break through the barriers set up by the patriarchs. In Seon practice, one can become a patriarch, free from life and death, after one has broken through the completely closed, gateless barrier called the “hwadu.” Patriarchs use hwadus as their own distinctive language to block all thought and discrimination by practitioners. This language cannot be understood by ordinary thinking. A hwadu has the power to sever all discriminating thoughts on the mundane level. That’s why hwadus are sometimes called “extraordinary words.”

To such questions as “Why did Bodhidharma come from the West?” or “What is the truth?” answers like “The cypress tree in the courtyard” and “A dry shit stick” are extraordinary words on an absolute dimension that transcends the relative dimension. These words contain inherent truth which is not approachable by words or thought. One can attain enlightenment upon just hearing these hwadus.

A hwadu is also called a gongan (公案; public case) or a gochik (古則). The word “gongan” originally meant “official government documents.” In other words, it refers to absolute regulations to be observed that also provide standards.

Gongans record the sayings, activities and enlightened views of Seon masters. There are as many as 1,700 gongans. They are the result of the opportune conditions and behaviors of the 1,701 Seon masters who appear in the Record of the Transmission of the Lamp (傳燈錄; Chuandeng lu). However, in reality, only 1,650 gongans are found in the major collections of gongan such as: The Gateless Barrier (無門關; Wumen guan), the Blue Cliff Record (碧巖錄; Biyanlu) and Compilation of Examinations of and Verses on Ancient Precedents (禪門拈頌; Seonmun-yeomsong).

  - excerpt from Buddhist English (Intermediate 2) published in 2014 by the Jogye Order of Korean Buddhism​​

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