Part 1: My "Emptiness" and "Nothingness"

Introduction -- My "Emptiness" and "Nothingness"

First, I will explain my own distinction between "ku" (emptiness) and "mu" (nothingness), which I will use throughout this article.

• Mu refers to the finite, changing aspect that appears in dependence on other things. It corresponds to mithya in Vedanta.
• Ku is a human experiential term referring to the Saguna Brahman side of Ishvara, which starts from sensory experience but transcends it.

If it is written briefly, it would be like this:

Sky → Refers to the Sattiya side and the Ishvara side. Emptiness → Refers to the limited and changeable Mitya side.

However, this is a provisional placement for explanation purposes. It does not mean that "ku" (emptiness) is the formal alternative name of Ishvara. Also, "mu" (nothingness) does not mean complete non-existence.

Furthermore, what I am referring to with the term "emptiness" is not the attributeless Nirguna Brahman itself. It is the Ishvara aspect of Brahman, which is spoken of in relation to cause, order, and function within the world.

Here, there is another important reservation.

Silence, clarity, light, dark clouds, energy, the arising and disappearing of thoughts – all that appears as experience exists within the realm of sensations and perceptions. No matter how deep, vast, or mysterious these feelings may be, the sensation itself is not Ishvara or Brahman. Ishvara and Brahman transcend such sensory experiences.

Therefore, what I call "emptiness" is not the name of a state where one directly perceives Ishvara through sensation. It is a word used to refer to aspects that cannot be reduced to experience itself, while using experience as a reference point.

In this article, I will first establish my own distinction, and then proceed to discuss Buddhism, Mahayana Buddhism, Esoteric Buddhism, Vedanta, and the Heart Sutra in that order. Finally, I will return to this distinction once again.

Chapter 1: Dividing "Nothing" into Three

"Mu" and "ku," in everyday language, both seem to represent "nothing." However, when comparing philosophies, assuming that the same characters have the same meaning can lead to confusion.

First, in everyday language, "mu" represents an absence of something.

• There is no cup on the desk.
• There is no money in the wallet.
• There is nobody in the room.

At that time, it was not as if the entire world disappeared. What is missing has already been decided beforehand.

In Buddhism, even in concepts like impermanence (mujo), no-self (muga), and emptiness of inherent existence (mujishin), there is something that is being negated.

• Mujō: The concept that nothing is permanent and everything is constantly changing.
• Muga: The absence of a fixed, independent self or ego.
• Mushinsei: The idea that there is no inherent existence or essence that exists independently.

On the other hand, in this article, when I use the term "mu," it does not simply mean absence. It refers to a unique usage that encompasses all things that are finite, changeable, and exist dependently.

Expression	Meaning in this article	Precautions
Absence of everyday language	The absence of something specific	Not the non-existence of everything in the world
Emptiness (Sunyata) in Mahayana Buddhism	The lack of fixed and independent self-nature in phenomena	Do not place an ultimate reality called "emptiness" behind it
My concept of "no-thingness"	The finite, changing, and dependent side that appears	Overlaps with the concept of "mitaya," but is not complete non-existence
My concept of "emptiness"	An experiential term referring to the Ishvara side beyond perception	Do not claim conceptual identity with Buddhist emptiness or Ishvara

After organizing these points, we will proceed to each of the ideologies.

Part 2: From Buddhism to Mahayana Buddhism and Emptiness

Chapter 2: The Entrance to Buddhism - Impermanence, No-Self, and Dependent Origination

The basic entry points of Buddhism include impermanence, no-self, and dependent origination.

The body changes. Emotions, thoughts, and memories also change. Nevertheless, we feel that there is something unchanging "I" somewhere within us.

Therefore, I observe whether the body is me, or if emotions are me, or if memories, will, and consciousness are me. Since all of these arise under certain conditions, change, and do not always go as planned, it is impossible to find an eternal and independent self within them.

The concept of "no-self" does not mean that even ordinary humans do not exist. There are people who have names, make promises, eat meals, and interact with others. However, it means that they do not exist as a fixed core that is independent of anything else.

The river has a name and is shown on maps. However, the water constantly changes, and the riverbanks also change. This does not mean that the river does not exist. It exists as a river because many conditions continue to be related to it.

People and things arise depending on causes and conditions. Things that arise due to conditions change. If you grasp them as an independent, eternal "I" or "my possessions," it creates a discrepancy with reality, which leads to suffering.

Here, what is being negated is not all experiences. It is the idea that there exists a self that is independent, unchanging, and completely controllable within changing experiences.

Chapter 3: Mahayana Buddhism - Existence exists, but there is no fixed essence.

In Mahayana Buddhism, this viewpoint is extended from human self to all things.

Suppose there is a cup in front of you. The cup exists as a result of various conditions, such as the materials it's made of, its shape, who created it, the tools used to make it, its purpose, its parts, its name, and how the person viewing it perceives it.

Then, where is the "cup itself," which exists independently of all other conditions?

Even when searching, it is not possible to find a fixed essence within the cup that solely constitutes and defines the cup. The cup exists, but it does not exist as something independent with its own inherent nature.

In short, it can be summarized as follows:

Existence is. However, within it, there is no fixed, absolute, and unchanging independent entity.

Here, when I say "it has no content," it does not mean that it lacks properties or functions. It means that it lacks an immutable core that independently governs its existence.

Because it does not have a fixed self, it can change and function based on causes and conditions, and relate to other things. If a seed were an eternally unchanging entity, it would not be able to sprout.

The sky is not a word that erases the world. It is a word that prompts us to reconsider how the world exists.

Furthermore, even emptiness itself is not made into a fixed entity. If one were to think that "there is an essence called 'emptiness' behind everything," then one would be creating a new self-nature for emptiness. In the Middle Way (Madhyamaka), emptiness is also empty.

In Mahayana Buddhism, there are concepts such as Madhyamaka, Yogacara, and the Tathāgatagarbha doctrine. The explanation of emptiness is not uniform. Here, we will use explanations related to Prajñā and Madhyamaka centered on the concept of "emptiness of inherent existence" as a comparative basis.

Part 3: Esoteric Buddhism and Vedanta

Chapter 4: Esoteric Buddhism - Not Ending with Just Emptiness

Esoteric Buddhism is not a religion separate from Mahayana Buddhism; it develops based on Mahayana's understanding of emptiness.

Furthermore, if we compare the two sides' core values in a very broad sense, they can be organized as follows:

In the Prajnā and Madhyamaka traditions, one discerns that there is no fixed essence, and unravels substantialism.

In Esoteric Buddhism, emptiness is not merely a concept to be understood intellectually, but it must be experienced and practiced as something related to manifestation and function.

This difference can be expressed in a basic way as, "In Esoteric Buddhism, there is an active recognition of something called 'emptiness'."

However, this does not mean that Esoteric Buddhism transformed emptiness into an eternal and unchanging object. It deals with the fact that emptiness and phenomena are not separate through concrete forms such as Buddhas, Bodhisattvas, mandalas, mantras, mudras, body, light, and colors.

Appearance, sound, body – all of these function. However, they do not function as independent and fixed entities. Understanding emptiness and living in the world of form are not two separate realms.

Points to Consider	Prajnā/Madhyamaka School	Esoteric Buddhism
Focus	Perceiving emptiness (sunyata) and dismantling substantialism.	Embodiment of emptiness, living the function of emptiness and manifestation.
Relationship with Phenomena	Emptiness and phenomena are not separate.	Practically embodying the non-separation of emptiness and manifestation.
Points to Note	Even emptiness itself should not be reified.	Do not treat emptiness as an eternal and unchanging object.

From the perspective of viewing the sky not as a mere absence, but from the aspect related to its manifestation and function, what I am saying feels closer to this Esoteric Buddhist direction than the explanation of emptiness (sunyata) in Mahayana Buddhism.

However, this does not mean that Esoteric Buddhism equates the concept of "emptiness," Dainichi Nyorai (the Great Sun Buddha), Dharmakaya, and Ishvara as being the same entity. The similarity lies in the direction of explanation, but it is not an identity on a doctrinal level.

Chapter 5: Vedanta - Maya and Satya

From here on, I will mainly discuss Advaita Vedanta in the Shankara tradition.

Even in Advaita, the body, emotions, thoughts, memories, and personality that one usually considers to be "me" are not seen as the true self itself. What is observed, known, and changes are each distinguished as "not just this is the ultimate me."

However, Advaita's negation does not lead to the conclusion of "nothing remains."

• Mitiya is something that appears and functions, but it itself is not an independent and unchanging reality.
• Satiya is a reality that does not depend on anything else and cannot be eliminated by negation.

Let's consider pottery and clay.

The pottery has a name, and it functions to hold water. However, if the shape is broken, the name "pottery" and its function are lost. Even so, the clay itself is not completely gone.

Pottery exists. However, it is not pottery that is independent of clay, but rather pottery that exists solely by relying on the clay. It appears with a name, shape, and purpose, while its existence depends on the clay.

The purpose of this analogy is to illustrate the distinction between something that depends on and appears from something else, and the entity that supports its existence. It does not mean that Brahman is a substance like clay, and the world is a processed product.

Category	Description
Complete non-existence	Something that is impossible, like a square circle.
Mittaya	Something that appears and functions, but does not exist independently on its own.
Satiya	The side that enables the existence of dependent phenomena without relying on anything else.

The body, emotions, thoughts, and personality also appear and function within experiences. However, they become objects that change and are known. Instead of discarding them as "non-existent," we distinguish them as "not the ultimate me."

The object of negation is not the existence of a phenomenon itself, but rather the mistaken identification of miṭṭha as sati.

Part 4: What to See After Negation

Chapter 6: Why, even when negated, does nothing disappear?

In Vedanta, there is a negation expression called "neti neti," which means "not this, not this."

I am not just a body. I am also not just emotions. I am not even just thoughts, memories, roles, or names. One by one, I distinguish things that are visible, conceivable, and changeable from my true self.

This method does not negate existence itself, but rather removes limitations, attributes, concepts, and incorrect identifications that are superimposed on existence and consciousness.

"I will consider 'I do not exist'."

This sentence denies one's own existence. However, for that negation to occur, a thought of denial must arise, and it must be known. If there were absolutely no existence or consciousness, even the negation "I do not exist" would not be possible.

In this context, "consciousness" is not a special state such as excitement, tranquility, ecstasy, or clarity. It is the fundamental basis that makes it possible for those states to appear, change, and be known.

"To remain that which cannot be denied" does not mean discovering a single shining object after everything else has been removed. Even if something tangible can be negated, the fact that the subject is known cannot be erased in the same way as negating the subject itself.

Advaita understands this indescribable existence/consciousness as Satya, which is Atman = Brahman.

Negation does not create satya anew. It exists prior to negation, and is understood as something that cannot be completely negated.

Chapter 7: The Point Where Madhyamaka and Advaita Diverge

In Madhyamaka and Advaita Vedanta, there are partially similar movements in that they both aim to move away from a substantial view of a fixed self or ultimate reality.

However, it differs in how to interpret what follows the negation.

In the Middle View, at the end of the analysis, it does not posit an unchanging basis that exists independently. If one were to say "everything is emptiness" while simultaneously positing a permanent and unchanging essence of emptiness behind phenomena, then one would be attributing self-existence to that emptiness.

In Advaita, existence and consciousness are not objects that can be found through analysis. They are preconditions that already exist whenever any object is negated; they themselves cannot be negated. Negation does not eliminate Satya (truth); rather, it removes the limitations imposed upon Satya.

Viewing Point	Middle View	Advaita Vedanta
Issue	Attributing fixed and independent self-nature to people and things.	Misidentification with the body, mind, personality, etc.
Negation	Avoid substantialism.	Distinguish what can be objectified from the true Self.
After Negation	Do not make emptiness a new basis.	Understand that which cannot be negated as Satya (truth).
Ultimate Interpretation	Do not posit an unchanging Atman or Brahman.	Recognize a non-dual reality where Atman = Brahman.

The difference is not that one lacks a negation, while the other is thorough. It's about what we call "substance," and how we think negation reveals something – it's a different philosophical interpretation.

Here, if only my comparison model is applied first, confusion will occur.

I leave my own understanding of emptiness on the side of Satya. On the other hand, in Madhyamaka, even emptiness itself does not become substantialized. Therefore, it may appear that "Mahayana Buddhism negates everything up to Satya."

However, the same character "ku" (meaning sky) is used with a different meaning.

Term	Meaning
Chūkan no kū	The absence of inherent and independent existence in all phenomena.
Watashi no kū	A human-side experiential term referring to the Ishvara side that transcends perception.

When Chūkan says, "Even emptiness is also emptiness," he is not negating what I am referring to with the word "emptiness" using the same definition.

Conversely, it cannot be said that "what Buddhism denies is actually Maya, and what remains is Sunyata." In this case, we would be placing Advaita's conclusion first and then fitting Buddhism into that framework.

The only similarity is that the object being negated resembles the finite, mutable, and dependent aspect (mithya) in Vedanta. The point where they diverge is whether to acknowledge Satya after negation.

Chapter 8: Why is my sky on the side of Ishvara, and not Nilguna?

What I am referring to with the word "void" is not Nirguna Brahman itself, but rather the Ishvara aspect of Saguna Brahman.

Nilguna transcends attributes and limitations. On the other hand, Ishvara is spoken of in relation to the cause, order, and function of the world.

In my usage, "ku" (space) refers not to a void after the disappearance of everything in the world, but rather to the aspect that establishes, orders, and functions within the manifested world. Therefore, in the comparative model, I place it on the side of Ishvara, rather than Nirguna Brahman itself.

However, being "saguna" does not mean that it can be directly grasped by human senses.

Nirguna Brahman, not as Saguna Brahman, the Ishvara. ↑ Cannot be grasped by sensation itself. It is referred to using the human experience word "emptiness."

In the past, things related to the sky, such as silence, brightness, dark clouds, and fundamental energy, as well as the arising and disappearing of thoughts, were also sensory phenomena. Since they appear, change, and can be observed, they are not themselves Ishvara or Brahman.

Even when leaving the word "sky," it is because we start from sensory experience, but also point to aspects that cannot be reduced to it.

My Terminology	Meaning	Correspondence with Vedanta
無 (Mu)	The finite, changeable, and dependent side that appears.	Overlaps with Maya.
空 (Ku)	An experiential term referring to the Ishvara side beyond sensation.	A provisional designation indicating the Sattva side.

This table does not replace the strict doctrinal system of classical Advaita Vedanta. It is a comparative model to explain my own experiences and understanding of the world.

Part 5: The Heart Sutra and Meditation Experiences from Several Years Ago

Chapter 9: The Heart Sutra - Basic Principles of "Form is Emptiness, Emptiness is Form"

The famous passage in the Heart Sutra is:

[...text...]

Form is emptiness. Emptiness is form.

"Color" is not merely a hue. It's a word that originates from concrete things and material forms. In the Heart Sutra, the five aggregates (skandhas) of color, feeling, perception, formation, and consciousness are discussed, and the relationship between color and emptiness extends to the remaining four aggregates.

Color is emptiness, and emptiness is color.

Things that have form exist. However, they do not possess a fixed essence that exists independently of all other conditions and stands on its own.

The color disappears once, and then changes to a different state called "ku" (emptiness). However, the way in which it exists as a color is from the beginning an emptiness.

Emptiness is form.

Then, is there another world or a core entity behind colors?

In the basic reading of Prajñāpāramitā and Madhyamaka teachings, it is not thought that way. Emptiness (śūnyatā) is neither a substance that remains after colors have disappeared, nor a substrate hidden behind phenomena. What we call emptiness is the state where color arises depending on causes and conditions, without possessing a fixed self-nature.

Color is not a fixed entity separate from the sky. The sky is also not a fixed entity separate from color.

This is the basic principle from the Buddhist perspective: "Form is emptiness, and emptiness is form."

Chapter 10: A Meditation Experience from Several Years Ago

Several years ago, I was trying to understand "color is emptiness and emptiness is color" through a certain meditation experience.

At that time, the central understanding was as follows:

From the fundamental energy, which we call "the void," thoughts and concepts take shape and appear.

The thoughts and concepts that have appeared return to the fundamental energy again.

From a place where miscellaneous thoughts and concepts feel like black, hazy, flat clouds, they appear as if balloons are inflating, and then recede. The area beneath them was perceived as the sky, and the thoughts and concepts that emerged from there were captured as colors.

And, colors appeared in the sky, and the colors returned to the sky, which I associated with the concept of "emptiness is form, form is emptiness."

At that time, I felt that the term "fundamental energy" resonated with me more than the word "emptiness." This interpretation explained the generation and disappearance of thoughts observed during meditation.

Currently, I consider this moment's silence, clarity, the things like black clouds, and the fundamental energy, as well as the generation and disappearance of thoughts, to all be sensory phenomena.

They appear as experiences, are observed, and change. I do not think that they themselves were Ishvara or Brahman. Ishvara and Brahman transcend them.

It is not necessary to delete past interpretations. They are records of what was experienced at the time and how one tried to understand it using available knowledge. However, they should not be treated as proof of current existence.

Part VI: The Current "Ku" (Emptiness) Model

Chapter 11: Reinterpreting the Heart Sutra from a Contemporary "Emptiness" Model

From here on, this is not a standard interpretation of the Heart Sutra, but rather my own reading based on comparative models.

The Heart Sutra is a text that originates from material forms. My own expanded interpretation extends it to encompass all finite phenomena, such as the body, objects, thoughts, emotions, individuals, and society.

色即是空 - Finite things do not exist separately from the realm of Sattiya.

Things that appear as colors are finite, change, and depend on other things. In this sense, they are phenomena (mittaya), and exist on the side of "emptiness" that I am referring to.

However, Mittiya is not a complete non-existence. It appears, relates, and functions. Its existence does not stand on its own; it cannot exist separately from the Sattiya side.

If we read "Shikikanazukō" in this context, it would be like this:

The finite things that appear as colors cannot exist separately from the Sattiya side, which we call "sky."

Colors do not exist solely as colors.

The color is not negated and disappears. Rather, the view that color is an independent reality is denied, and it is understood that its existence is not separate from what we call "emptiness."

Emptiness is form – emptiness is not an empty void that is unrelated to form.

The Ishvara that I refer to by the word "ku" is spoken of in relation to the cause, order, and function of the world.

Therefore, the sky is not an empty void that excludes all phenomena. It is not a nothingness unrelated to the finite world, but rather refers to the aspect related to the existence and function of the world.

However, we do not equate Ishvara with specific phenomena experienced in the world, such as silence, light, brightness, dark clouds, or energy.

The sky is not an emptiness unrelated to color.

The Ishvara referred to by the word "sky" is spoken of in relation to the cause, order, and function of the world.

However, no sensory color itself is Ishvara.

Here, "the sky changes color" does not mean that the substance of the sky is changing and becoming an object. It also doesn't mean equating each individual thing directly with a deity.

Finite forms do not exist by themselves; they are inseparable from the "emptiness" that surrounds them. And this emptiness is not spoken of as a void unrelated to the finite world. However, it does not mean that Ishvara is perceived as a sensory phenomenon. I interpret this relationship as "Emptiness is Form."

Chapter 12: What Separates My Interpretation from Buddhist Teachings

Finally, I will summarize the differences between the two in a table.

Phrase/Point	Basic interpretation of Prajnā and Madhyamaka teachings	Interpretation by my current model
Shikki zoku ze kū (Form is emptiness)	Form does not have a fixed, independent essence.	Finite form is rupa, which exists separately from the realm of truth.
Kū zoku ze shikki (Emptiness is form)	Emptiness is not a separate entity apart from form.	Emptiness does not refer to nothingness, but rather points to the aspect of Ishvara in relation to the cause, order, and function of the world.
Handling of emptiness	Do not treat even emptiness as a fixed entity.	Use it as an experiential term referring to the aspect of Ishvara that transcends sensation.
Immutable existence	Do not posit Atman or Brahman.	Acknowledge the truth that cannot be completely negated.

My interpretation does not correct the official interpretation of the Heart Sutra. It is a comparative interpretation that re-reads the words of the Heart Sutra based on Vedanta knowledge and my own experiences.

We do not equate Buddhist emptiness (sunyata) with Brahman. We also do not equate the concept of emptiness in Esoteric Buddhism, Dainichi Nyorai (Great Sun Buddha), and Ishvara as being the same entity.

I am looking at different structures from the same words. It is necessary to avoid hiding those differences in this comparison.

In conclusion: Finite nothingness, and emptiness that transcends sensation.

In Mahayana Buddhism, "emptiness" does not mean that "nothing exists." It means that while existence is present, there is no fixed and independent essence within it.

Esoteric Buddhism does not limit emptiness to a mere negation, but deals with the function of emptiness and manifestation in practice.

Vedanta also denies the false identification with things like the body, mind, and personality. However, it does not mean that nothing remains after such denial. Even when denying the finite and changing world of phenomena (maya), one cannot deny the existence or consciousness that makes negation itself possible. This is understood as Satya.

Based on this flow, let's return to my own distinction in the beginning.

Everything that appears in a finite form changes. However, it does not mean that it doesn't exist. It currently manifests, relates, and functions, but is itself not an immutable reality. I call this finite and changing aspect "emptiness," and associate it with the term "mittaya."

On the other hand, "the sky" is not a specific state of sensation such as tranquility or brightness. Things that were previously thought of as "the sky" or fundamental energy are now seen from the present perspective as sensory phenomena that manifest as experiences.

Ishvara and Brahman transcend those senses. Nevertheless, starting from sensory experiences, I use the word "ku" to refer to the aspect of Ishvara that goes beyond those senses.

"Emptiness," starting from sensory experience, is a term used to refer to the aspect of Ishvara as Saguna Brahman, which transcends that experience.

"Non-existence" refers to the finite, changing, and dependent side that manifests.

Buddhism and Vedanta have partially similar procedures in negation. However, they differ in what is seen after the negation.

My distinction between "ku" (emptiness) and my own self is not intended to erase the difference. It is, rather, a way for me to express, in my own words, the relationship between finite and changing manifestations, and that which transcends those sensations.