What this concept is saying
一如 (*eka-tathatā*, “the one suchness” or “undivided suchness”) means that all phenomena, in their true nature, are equal and nondual. This does not mean that all things look alike, function alike, or have the same conventional value. It means that none possesses a sealed-off, independent essence by which it could stand absolutely against everything else.
A red light is not a green light; kindness is not cruelty; medicine is not poison. Their differences remain “clearly distinct” (歷歷不爽). Yet none exists solely from its own side: each appears through conditions, relations, perception, language, memory, and causes without limit. When the mind stops turning these useful distinctions into absolute divisions—self versus world, success versus failure, pure versus impure—the many things are seen without being imprisoned in “two sides.” That unobstructed reality is called 一如.
The pivotal line is:
“When the mind is not divided, the myriad phenomena are of one suchness.” 心若不異，萬法一如。
This wording appears in the *Jingde Record of the Transmission of the Lamp* (《景德傳燈錄》), quoting the *Inscription on Trust in Mind* (《信心銘》). The received text of the latter has the slight variant 心如不異，萬法一如. The *Xinxin Ming* is a Chan verse traditionally associated with the Third Patriarch Sengcan, not a Buddhist sūtra in the strict classificatory sense.
“Mind not divided” does not mean suppressing thought or becoming incapable of discernment. It means not adding self-made antagonism to what appears. Ordinarily, the mind does more than recognize difference. It immediately appropriates it:
- this benefits me, so it must remain; - that threatens me, so it must disappear; - this opinion confirms who I am; - that person’s disagreement diminishes who I am.
From differentiation comes grasping; from grasping come attraction, aversion, defensive identity, and suffering. 一如 concerns the point at which difference has not hardened into dualistic bondage.
The classical sources unfold this in several inseparable dimensions.
First, there is 萬法一如 (*wànfǎ yīrú*, “all phenomena are of one suchness”). This is not a human act of forcing multiplicity into a metaphysical One. The ten thousand things remain ten thousand things. Their equality becomes evident when the mind no longer selects and rejects them from the standpoint of an imagined independent self. Hence the *Xinxin Ming* says:
“If the eye does not sleep, all dreams naturally disappear.” 眼若不眠，諸夢自除。
The image is precise. Awakening does not need to negotiate with each dream-object and make them agree. Once waking occurs, the entire structure that made the dream seem independently real is understood at once. Likewise, nondual awareness does not flatten the world; it exposes the mistaken framework through which the world had been divided into an isolated observer and independently existing objects.
Second, 一如 is “deep and beyond comparison”:
“The substance of one suchness is profound; standing alone, it forgets conditioning thoughts. Regarding the myriad phenomena equally, it returns to what is naturally so.” 一如體玄，兀爾忘緣。萬法齊觀，歸復自然。
“Forget conditions” here should not be read as denying causality or becoming oblivious to circumstances. It points to the cessation of 攀緣—the mind’s compulsive reaching, fastening, and constructing itself through objects. One still sees circumstances clearly, but no longer needs to extract a permanent self from them.
Third, 一如 is 不二 (*advaya*, “nonduality”), but even “one” must not become an object of attachment. The *Xinxin Ming* says:
“Two exists because of one; do not hold even to one.” 二由一有，一亦莫守。
And again:
“When the two cannot be established, how could the one remain?” 兩既不成，一何有爾。
This prevents a major philosophical mistake. 一如 is not monism—the doctrine that a single cosmic substance is the only real thing. If “the One” is set against “the many,” duality has merely returned in subtler clothing. The word “one” is therapeutic: it heals division. Once division is released, one must not reify the medicine.
Fourth, there is the mutual inclusion of one and all:
“One is all; all is one.” 一即一切，一切即一。
This does not mean that a teacup is conventionally identical to a mountain. It means that no phenomenon can be isolated from the boundless network that lets it be what it is. A cup includes clay, heat, labor, transport, culture, thirst, perception, and the concepts by which it is recognized. Remove all conditions and no self-existing “cup” remains. In that sense, one phenomenon opens into all phenomena, while the whole is present through each particular configuration.
Fifth, 一如 is experienced as 根境一如 (*gēn-jìng yīrú*, “sense faculty and object are of one suchness”) and the cessation of 能所 (*subject and object*):
“Faculty and object are of one suchness; subject and object are cut off.” 根境一如能所斷。
This line from the *Extensive Record of Chan Master Hongzhi* (《宏智禪師廣錄》) does not claim that eyes and visible forms become materially identical. It points to lived experience before conceptual appropriation. In seeing, “seer” and “seen” arise together. There is no independently findable observer standing behind experience, just as no experienced object appears apart from the conditions of experience. Their distinction remains conventionally serviceable, but their imagined absolute separation falls away.
Sixth, there is 心心一如 (*xīnxīn yīrú*, “mind after mind in one suchness”). Hongzhi describes the forgetting of self and other and the subsiding of oppositional right and wrong, while round and square, large and small, remain unmistakably clear. This is crucial: 一如 eliminates fixation, not intelligence. It does not confuse shapes, erase persons, or abolish moral responsibility. Because the defensive self is no longer the compulsory center, response can become more accurate and compassionate.
Seventh, 平等一如相 (*the aspect of equality and one suchness*) must be placed “upon the myriad forms themselves” (著在森羅萬像頭). Equality is not hidden in a spiritual realm behind appearances. It is disclosed in changing appearances themselves. Hongzhi describes its functioning as:
“Silent without congealing; illuminating without being swept along.” 默而不凝，照而不流。
Silence without congealing is not numb withdrawal. Illumination without being swept along is not restless reaction. Together they describe a mind intimate with experience but not captured by it.
This locates 一如 within the path of liberation. Ignorance does not consist merely in lacking information. It is the lived habit of treating conditioned constructions as independent realities, especially the construction called “I.” That habit produces grasping and rejection; grasping and rejection sustain suffering. Ethical discipline weakens the actions through which self-centered fixation reproduces itself. Meditative stability makes the mind less compelled by every attraction and aversion. Wisdom sees that self and phenomena are empty of independent essence. 一如 names how reality is disclosed when that wisdom is no longer merely conceptual: empty yet vivid, differentiated yet undivided, silent yet responsive.
A walkthrough in everyday life
Imagine an evening commute after a difficult day. You are standing in a crowded train, looking at your phone. A message from your manager appears: “We need to revisit your work tomorrow.” At almost the same moment, your partner sends: “You forgot again.”
Begin with what actually appears. There are colored shapes on a screen, bodily pressure in the chest, heat in the face, sounds in the carriage, remembered conversations, and meanings recognized through language. These are distinct conditions. 一如 does not ask you to pretend that the manager, the partner, the phone, and the tightening chest are one homogeneous substance.
Then notice the division being manufactured:
1. The message becomes “what is being done to me.” 2. A threatened “me” seems to appear behind the chest pressure. 3. The manager becomes an opposing object: “the person judging me.” 4. Your partner becomes another opposing object: “the person who never understands how much pressure I am under.” 5. Thought begins selecting evidence for both sides—innocent self, unreasonable others.
The classical teaching calls attention to precisely this root-object and subject-object structure. The screen is not inherently an attack. Nor is your distress imaginary: it has real conditioned force. But “attacker,” “victim,” and “unbearable threat” are being assembled through sensation, memory, expectation, language, and self-protection.
Pause without trying to erase any of it. Feel the tightening as tightening. See the sentence as a sentence. Recognize fear as fear and anger as anger. Here “mind not divided” does not mean, “I should not feel angry.” That would divide experience again, placing a supposedly spiritual self against an unacceptable emotion.
Instead, let each condition be distinct without making it an absolute camp. The anger depends on fear; the fear depends on uncertainty; the uncertainty depends on caring about livelihood, competence, and belonging. Your manager’s message likewise depends on circumstances you cannot yet see. Your partner’s complaint arises within a history of promises, fatigue, need, and disappointment. Each apparent unit opens into countless conditions: 一即一切，一切即一.
Now 根境一如 becomes practical. When you look at the message, examine whether you can find a separate “seer” outside the seeing. There is visual form, recognition, bodily response, and thought. The sense of “I am under attack” arises within that field; it is not an independent owner standing beyond it. Likewise, the message as experienced is inseparable from language, attention, context, and memory. Subject and object have not become the same object; their supposed absolute separation has become unfindable.
From this, action may become simpler. You might reply to your partner: “You’re right—I forgot. I’m on the train and feeling defensive, but I don’t want to turn that into an excuse. I’ll handle it when I arrive.” You might wait until morning before answering the manager, when you can ask what specifically needs revision.
This is not passivity. Distinctions remain clear: a forgotten responsibility should be addressed; vague workplace criticism may need clarification; abuse, if present, should be named and resisted. What has weakened is the demand that every encounter confirm or destroy a fixed self.
The most common mapping error here is to identify 一如 with the calm feeling after the pause. Calm is conditioned and may or may not come. One suchness is not a mood. Even agitation, seen without appropriation or exclusion, does not stand outside suchness.
Consider another moment: scrolling through social media late at night. An algorithm presents a successful peer, an alarming headline, an attractive product, and a post that provokes moral outrage. Technically, ranking systems select content according to inferred patterns and platform goals. They can amplify your habits, but the algorithm is not an exact analogue of Buddhist karma, and current cognitive science does not prove the Buddhist account of mind.
Still, the comparison can illuminate something. The feed continually trains selection: want this, reject that, become this kind of person, despise that kind. Your own discriminative habits and the platform’s optimization processes condition one another. The “inner” desire and “outer” feed are not independent domains. In this limited sense, “inside and outside are of one suchness” (內外一如) becomes experientially relevant.
Practice here does not require declaring all posts equally trustworthy or wholesome. It means seeing the entire event without immediately being recruited by it: image, bodily pull, comparison, memory, commercial design, and the thought “my life is inadequate.” The contents remain different; their empty, conditioned nature is equal. You can then close the app—not because the phone is impure and silence is pure, but because wisdom still distinguishes what conduces to freedom from what strengthens compulsion.
Why contemporary people need it
Contemporary life profits from turning distinctions into identities. Preferences become profiles; disagreement becomes tribal membership; productivity becomes personal worth; attention becomes a commodity. We are repeatedly invited to experience every difference as a verdict about who we are.
一如 interrupts this mechanism at its root. It does not merely offer stress reduction. It questions the apparently solid subject who must constantly be secured through achievement, recognition, possession, or victory.
This has several liberating consequences.
In intimate relationships, it allows difference without immediate estrangement. Your partner’s pain need not be either wholly correct or an accusation that annihilates your goodness. You can hear it as a conditioned reality without making either person into a fixed essence.
In parenting, it helps distinguish a child’s conduct from the child’s identity. A harmful action requires correction, but “you did something harmful” need not harden into “you are a bad child”—or “I am a failed parent.” Clear boundaries and non-reification can coexist.
At work, it separates responsibility from self-condemnation. A mistake has causes and consequences and may require repair. But it does not reveal an eternal, defective self. Nor does success establish an eternal, superior one.
In public life, 一如 provides a basis for compassion without sentimental sameness. If self and other are not absolutely separate, another’s suffering cannot be dismissed as wholly external. Yet compassion must remain discerning: one may protect a victim, restrain an aggressor, and oppose injustice without treating any person as possessing an immutable evil essence.
In meditation, it prevents practice from becoming a private campaign to manufacture a purified inner state. Hongzhi’s “silent without congealing; illuminating without being swept along” holds together stillness and responsiveness. Liberation is not hiding from the myriad forms. The “aspect of equality and one suchness” must appear precisely amid them.
Most importantly, 一如 loosens fear of change and loss. The sources speak of phenomena as coming from nowhere fixed and going nowhere fixed: 来無所從，去無所向. This does not deny ordinary arising and passing. It means that no independently existing thing travels intact from a metaphysical origin to a metaphysical destination. What we call arrival and departure are relational designations within continuous conditional transformation.
When this is seen deeply, impermanence remains poignant, but it need not be interpreted as an assault upon a permanent owner. Life is not made safe by freezing it. It becomes inhabitable because neither the one who clings nor the object clung to possesses the solidity we had attributed to it.
Common misunderstandings and clarifications
“One suchness means everything is literally the same.”
No. Hongzhi explicitly preserves the clarity of round and square, large and small. Conventional differences and causal consequences remain. Fire burns; medicine may heal; lies and truthful speech condition minds differently. Equality of true nature is not equivalence of function.
“It means good and evil are indistinguishable.”
No. 一如 dissolves reified opposition, not ethical discernment. Nonduality means that wholesome and unwholesome acts lack independent essence and arise through conditions. It does not mean that they produce identical suffering or freedom. Indeed, seeing conditionality more clearly makes careful conduct more urgent: actions shape the field shared by self and other.
“It means I should never choose.”
The classical criticism of 揀擇 (*jiǎnzé*, compulsive picking and rejecting) is not a ban on practical choice. A physician chooses one treatment over another; a parent removes a child from danger; a practitioner cultivates wholesome states and abandons harmful ones. The bondage lies in self-centered fixation—believing that liberation depends on possessing one side and annihilating the other. Functional discernment can remain without hatred, craving, or identity-making.
“It is a cosmic substance called the One.”
No. The warning “do not hold even to one” directly blocks that interpretation. 一如 is not a super-object behind ordinary objects. If it were an absolute One opposed to the many, it would reproduce the duality it is meant to expose.
“It means consciousness creates the universe.”
The statement “when mind is not divided, all phenomena are of one suchness” does not by itself establish metaphysical idealism. Its immediate force is soteriological: discriminating fixation structures bondage, and when that fixation ceases, phenomena are disclosed nondually. One should not inflate a practice instruction into a theory that nothing exists beyond an individual mind.
“It is a blank state without thought.”
No. Hongzhi’s formulation is both silent and illuminating. Numbness, dissociation, and cognitive dullness may reduce felt conflict, but they are not wisdom. 一如 is vivid enough for differences to be “clearly distinct.” It is freedom from captivity to thought, not necessarily the absence of thought.
“Subject and object disappear, so ordinary reality becomes unusable.”
Their absolute separation ceases to be believed; their conventional distinction remains available. You still know which person is driving, which account is yours, and which promise you made. What disappears is the imagined independent subject standing outside the conditioned field of experience.
“If all is empty and of one suchness, suffering is unreal.”
Emptiness does not mean nonexistence. Suffering is empty because it arises through conditions, not because it is negligible. Precisely because it is conditioned, it can be understood, prevented, and transformed. Calling another person’s pain “all one” in order to avoid helping them is attachment to a slogan, not realization of 一如.
“AI or neuroscience has proven nonduality.”
No. Artificial-intelligence systems can show that apparently unified outputs arise from distributed conditions; neuroscience can investigate how perception and the sense of self correlate with bodily and neural processes. Such findings may offer useful analogies to conditioned construction. But scientific models operate through publicly testable measurements and remain incomplete and contested, while 一如 concerns the liberating penetration of experience and reality within Buddhist practice. Analogy is not identity, and neither domain should be used to grant cheap authority to the other.
Finally, 一如 must not become one more beautiful view to defend. The *Xinxin Ming* repeatedly dismantles both sides and then dismantles attachment to “one.” Its purpose is not to give the intellect a perfect description of reality. It is to reveal where the mind divides, appropriates, and suffers—and to let that movement cease.
Then the many things do not vanish. The train remains crowded, the message still requires an answer, the child still needs care, and grief still hurts. Yet none of these stands outside suchness, and no isolated self has to conquer the world before it can be free. This is why 一如 belongs at the heart of the path: it is not escape from the myriad forms, but freedom in their very midst.