One day, a student asked Korean Zen Master Seung Sahn, “What is Zen?”
Seung Sahn held his Zen stick above his head and said, “Do you understand?”
The student said, “I don’t know.”
Seung Sahn said, “This don’t-know mind is you. Zen is understanding yourself.”
Seung Sahn taught that in a cookie factory, different cookies are baked in the shape of animals, cars, people, and airplanes. They all have different names and forms, but they are all made from the same dough, and they taste the same.
In the same way, all things in the universe – the sun, the moon, the stars, mountains, rivers, people, and so forth – have different names and forms, but they are all made from the same substance. The universe is organized into pairs of opposites: light and darkness, man and woman, sound and silence, good and bad. But all these opposites are mutual, because they are made from the same substance. Their names and their form are different, but their substance is the same.
Names and form are made by your thinking. If you are not thinking and have no attachment to name and form, then all substance is one. The don’t-know mind cuts off all thinking. This is your substance. The substance of Seung Sahn’s Zen stick and your own substance are the same. You are the stick and the stick is you.
In this sense, not-knowing is a place where we haven’t yet created name and form. What we don’t know is formless – we haven’t put a name on it and therefore it doesn’t assume a form. When we practice true intimacy with not knowing, when we don’t know our own self, then we are formless and part of Seung Sahn’s cookie dough, the formless substance of the universe.
Dogen said that to study the way is to study the self, and to study the self is to forget the self (not-knowing). To forget the self is mind and body dropping away (formlessness), and experiencing mind and body dropping away is to enter realization.
Seung Sahn said Zen is understanding yourself, and that you are don’t-know mind. Same thing.