The practice or method of Hwadu (derived from the Chinese Hua Tou (話頭)) is a central component of the Korean Seon (Sŏn, 禪) Buddhist school that is better recognized in the West as Zen Buddhism of the Japanese school, both of which has their origins in Chan Buddhism. This practice was incorporated by Chinul who was a Korean monk of the Goryeo period, and is considered to be the most influential figure in the formation of Korean Seon (Zen) Buddhism.
The historical records seem to indicate that originally, the Hwadu practice was a fluid and dynamic exchange of questions and answers between a master and his student, that is reminiscent of the Socratic method documented by Plato within ancient Greek philosophy. A student could pose a question that is turn answered by a master and visa versa with the goal of demonstrating the realization of the original mind. These exchanges got documented and preserved in a collection by students that came to be known as kōans. These are a form of public case records.
Hwadu can be viewed as a part of the kōan that articulates the core topic of discussion within the kōan. It later evolved as form of inquiry which reaches a point beyond which you can talk explicitly about. In a sense, talking about it becomes exhausting and redundant. This is because in this deliberate process of questioning and answering, the mind naturally attempts to use the intellect, logic and rationality to think through the implications of the process of questions and answers. In contrast to the Greek philosophers who used the Socratic method to clarify rational thinking, kōans while applied through speech and writing that is a process of rational thought, they go beyond the limits of rationality to where intellectual understanding reaches its limits, according to Chinul. Chinul also points out that Hwadu acts as a purification process that filters out conventional conceptualization or thoughts. This allows the mind to be opened up to unconditioned or original thinking that lies beyond all ideas, speech, or discrimination.
So to ask, “Hwadu, what is this?” is to answer simply “Hwa-du”. Our minds, especially those influenced by Western philosophy would expect a systematic answer like the one outlined above, but one has to go beyond this, otherwise it will seem a nonsensical exchange. To elaborate further from a few key sources that you can find on the Internet, “What is this?” comes from an encounter between the Sixth Patriarch, Huineng, and a young monk who became one of his foremost disciples, Huaijang:
Huaijang entered the room and bowed to Huineng.
Huineng asked, “Where do you come from?”
“I came from Mount Sung”, replied Huaijang.
“What is this and how did it get here?”, demanded Huineng.
Huaijang could not answer and remained speechless.
He practiced for many years until he understood.
He went to see Huineng to tell him about his breakthrough.
Huineng asked, “What is this?”
Huaijang replied, “To say it is like something is not to the point. But still it can be cultivated”.
This would require you to sit in meditation (and contrary to popularized ideas, mediating is not a means to relieve stress, but is actually at least initially, a stressful, repetitive and disciplined process to achieve “awakening” and to be one with the universe) or to simply ask again and again, “What is this? What is this? What is this?” “What is it that moves? What is it that thinks? What is it that speaks?” This is not simply an epistemological question asking about how I know what I know about external objects: “What is the table? Does it exist only in my mind or outside it?” No, you have to turn back into your own experience of existence and ask “What is this in this moment?”
You have to be careful not to slip into a question of pure intellectual inquiry, for you are not trying to speculate on the mind, whether it exist outside or within your body, but that you are becoming one with the question. It is not the words that lead to the question, but rather the question mark (“?”) itself that is of supreme importance. You are simply asking unconditionally and uncritically “What is this?” without looking for an answer, nor expecting one, but rather to simply open yourself up and to absorb the sensation of wonderment. You are allowing yourself to merge within the world without the need for knowledge and security as there’s no place to rest as your body and mind become a question.
At this level of focus, we are returning to the question again and again. The question anchors us and brings us back to this moment. But this is not some mantra of repeating question again and again like a chant. These words are not sacred and it is meaningless how many times we repeat them. What is important is that the process of asking questions is live and in the moment, since each time we ask “What is this?” it is fresh since we are asking because we do not know. It is similar to when we lose some keys. We look and look and look and we have no idea where they are. We think “keys” and we don’t know and are left with this sensation of questioning only. In Seon Buddhism it is said: “Great questioning, great awakening; small questioning, small awakening; no questioning, no awakening.”
We as humans are composed of a body and a mind, but a body without the mind would be a body without life and a mind without a body is just a wandering soul. But these delineations are arbitrary, for Seon Buddhism would not look at these three as separate and distinct entities but as a whole working in concert. So all three must live in synchrony, but what makes that symphony of synchronicity work? It is the body working with the mind to awaken the soul through Hwadu.
Such a practice would not involve just sitting quietly so as to pacify the mind or calm the soul as is the common understanding in Western popularization. Nor does it entail simply contemplating the breadth and depth of the universe. Instead you must engage directly with Hwadu and even be in conflict to it. What you are searching for can be called by many different names: mind, spirit, soul, true nature and so forth. But such designations are merely labels of conventional thinking. You should banish these names and reflect on the fact that the true master of the body is more than just directing the mind to the soul. The master of the body and the mind is not the Buddha, for it is not yet awakened. Nor is it anything material for that entails that it can be physically given or received, which it cannot.
It cannot be simply transmitted through words and concepts, since it has be realized yourself, even though the notion of “self” is perpetually transitory. It cannot even be empty space, since empty space is nothing which cannot by its nature, contemplate on the nature of true reality, good and evil or living virtuously and authentically. But acknowledging “nothingness” entails that nothing is something, so what is that something of nothingness? We are formed from nothingness but nothingness comprises our inner and outer “Self”.
Having negated these possibilities, what would constitute being a master? There is no real master, since student can be the master and the master can be the student, but the point is to keep asking till the questioning become more and more intense. At some point, the barrage of questioning will reach its critical point and implode. The entire universe will be shattered and only your original nature will appear before you. In this way you will finally awaken.
My position is that while logical thinking is important, we do not want to be constrained by it so that the Original Nature becomes clear through a direct transmission from mind to mind. Since we are all Buddha by nature, it is only necessary to clear away ignorance and delusions for our true nature to come forward. To the Western trained mind that values reason and logic, this talk of “nothingness” is contradictory and nonsensical, for one cannot think of something unless one is something, but that is to miss the point of Hwadu. Of course you have to exist in order to cognate, but to only think and reason is to be constrained by conventional conceptualizations, so it is imperative to annihilate the self so as to fully realize the self and non-self (or what Buddhist refer to as “anattā” the “non-self”).
This is where body, mind and soul become all and none.