Translated and edited by Zen Master Dae Kwang, Hye Tong Sunim, and Kathy Park. 

Zen Master Man Gong (1872-1946) received transmissions from Zen Master Kyong Ho, and is a towering figure in modern Korean Zen. He was a pioneer in teaching Zen Buddhism to laypeople, and played a central role in re-establishing the Buddhist tradition in Korea after centuries of suppression during the Chosun dynasty. Zen Master Man Gong was the grand teacher of Zen Master Seung Sahn (1927-2004), the founder of the international Kwan Um School of Zen. 

In keeping with the Zen tradition, the exchanges between Man Gong and his students have exercised considerable influence on Zen students as teaching vehicles. 

Excerpt: "When I first started practicing, I took up the question, 'Ten thousand Dharmas return to the One. Where does the One return?' This kong-an has two levels. The best question for a beginner is 'What is the One?' Even though you keep questioning, you should enter the place of no thinking, which is clear and calm. Here, when even the questioning has gone away, you will see your true nature. The One neither exists nor does it not exist. It is not spirit, soul, or mind. Then what is it? As you question, keep your mind like a cat, single-mindedly watching a mouse. The question should be like water flowing, nonstop. If you keep the question sincerely, you will find the One, someday."