Yangshan was studying under Guishan. He asked, " What is the true abode of the Buddha?" Guishan replied, "To think the non-thinking through subtle reflection." Yangshan asked, "How does one think the non-thinking?" Guishan said, "It is not-thinking." Yangshan was enlightened. Later, he said to his assembly, "I was at Guishan's place and received his instruction, enabling me to penetrate the mystery. Now I ask you all: What did Guishan say to me?" A monk stepped forward and began to speak. Yangshan interrupted, "There is no such thing as mind. Do not slander the great compassion."