Master Baso [Mazu] knew that Taibai was doing solitary sitting in the mountains, so he sent an attendant to examine him. The attendant asked Taibai, “What did you realize at Baso’s before you came to the mountain?” Taibai replied, “Once I asked Baso, ‘What is Buddha?’ He answered, ‘Mind is Buddha.’ The instant I heard those words I attained deep realization. After that, I came to the mountain.”
The attendant said, “Recently Baso’s teaching has changed.”
“In what way?” asked Taibai.
“Nowadays Master Baso says, ‘No mind, no Buddha.’”
Taibai said, “The great master Baso perplexes many Zen students. He may say ‘No mind, no Buddha’ if he wishes to, but for me it will be, ‘Mind is Buddha’ until the end of the world.”
The attendant returned and reported this to Baso, who commented, “The plum has ripened.”
...
A monk asked Mazu [Baso], “Master, why do you say that Mind is Buddha?”
Mazu said, “To stop babies from crying.”
The monk asid, “What do you say when they stop crying?”
Mazu said, “No mind, no Buddha.”
The monk asked, "Without using either of these teachings, how would you instruct someone?"
Mazu said, "I would say to him that it's not a thing."
The monk asked, "If suddenly someone who was in the midst of it came to you, then what would you do?"
Mazu said, "I would teach him to experience the great way."