BODHIDHARMA'S GATE: "Chan (Zen) in fact is an "impregnable fortress", without a gate to enter. Suppose there is really a gate, that gate would simply be a method of training to be taken up in the Chan tradition. That is why when a monk asked Master Zhao Zhou (778-897): "Has a dog Buddha-nature or not?" Master Zhao Zhou retorted: "Wu." Later on, this Gongan (koan) formed part of a specific approach in the Chan School." The author , Venerable Jing Hui is a Chan Master and a vice-president of the Buddhist Association of China.