What this concept is saying
同根 (*tónggēn*, “sharing one root”) names the Chan insight that “Heaven and earth share one root with me; the myriad things are one body with me” (天地與我同根，萬物與我一體). The saying appears in the encounter between the official Lu Gen and Nanquan recorded in the *Recorded Sayings of Chan Master Dahui Pujue* (《大慧普覺禪師語錄》), where Lu cites it as a saying of Master Sengzhao.
At first hearing, it can sound like a grand theory: everything in the universe must have emerged from one primordial substance. But Chan is not chiefly proposing a cosmological origin story. “Root” is not necessarily an invisible material, a creator, a cosmic soul, or a thing lying behind appearances. It points to the fact that no phenomenon possesses a sealed, independent existence of its own. Self and world, mind and object, stillness and activity appear as distinguishable, yet they do not stand outside one another as self-sufficient realities.
This is why “one root,” “one source,” and “one body” illuminate different sides of the same teaching:
- 同根 (*tónggēn*, “one root”) says that no phenomenon is ultimately uprooted from the whole. - 一源 (*yīyuán*, “one source”) emphasizes that the ground cannot finally be divided into rival origins. - 一體 (*yītǐ*, “one body”) emphasizes the indivisibility of the living whole.
These are not three stages, nor three separate substances. They are three ways of loosening the same habitual picture: “I exist here by myself, while everything else exists over there by itself.”
The *Extensive Record of Chan Master Hongzhi* (《宏智禪師廣錄》) unfolds this insight along several inseparable dimensions.
First, its scope includes all phenomena. Hongzhi says, “From the beginning, the ten thousand dharmas share one root” (從來萬法同根), “the profusion of phenomena fundamentally shares one root” (森羅萬象本同根), and even “the two powers share one root” (二儀同根)—the “two powers” being heaven and earth, or the complementary poles through which the world is articulated. “All dharmas” here does not mean only noble, spiritual, or pleasant things. Body and landscape, affection and irritation, clarity and confusion, birth and decay all fall within its range. Nothing can be placed outside the field and then treated as wholly alien to it.
Second, its measure is said to equal empty space: “Ultimately, its measure equals space” (究竟虛空等量). This does not turn the shared root into an infinitely large object. Space is invoked because the point cannot be enclosed by a boundary, pictured as a shape, or possessed as “my realization.” Hongzhi therefore warns against forcibly “drawing a model and making a likeness” (剛地起模畫樣): the moment we imagine the one root as a vast spiritual object, we have divided ourselves from it and made it one item among others.
Third, it cannot be grasped by discriminating thought. “Do not, amid the various conditions, divide this from that” (莫向諸緣分彼此) does not mean becoming unable to distinguish a red light from a green one, medicine from poison, or kindness from abuse. Chan is not attacking functional discernment. It is exposing the deeper appropriation by which distinctions harden into supposedly independent essences: *my* side against *your* side, the pure world against the contaminated world, the observer safely outside what is observed.
Hongzhi compares the matter to cart tracks fitting the road as they leave the gate, and to peach and plum trees forming a path without speaking of it: “The cart tracks go out through the gate and naturally fit the measure; peaches and plums form a path without words” (車轍出門而合度，桃李成蹊而不言). The shared root is not manufactured by agreeing with a doctrine. It is already expressed in the unadvertised intimacy of conditions: rain entering roots, food becoming flesh, speech altering another person’s breathing, generations living within one gesture.
Fourth, essence and function are inseparable. Hongzhi describes its ground as “mysterious yet not dark, limpid as though present” (幽而不昏，湛而若存), and says, “Its essence reaches utter openness without a trace; its subtle functioning touches things and emerges beyond obstruction” (體至虛而無痕，用妙觸而出礙). The shared root is therefore not a dead sameness underneath a colorful world. Its openness is precisely capable of functioning as countless distinct appearances. Stillness does not cancel activity; activity does not depart from stillness.
A hand, a cloud, an argument, and a bowl of rice are not interchangeable. Their differences are real at the level of conditions, effects, and ethical responsibility. Yet difference does not require absolute separation. One root is not “everything is the same.” It is closer to saying: nothing can be itself alone.
This helps explain Nanquan’s famous response. When Lu Gen presented “Heaven and earth share one root with me; the myriad things are one body with me,” Nanquan did not offer a philosophical explanation. He pointed to a flower in the courtyard and said, “People of the time see this single flower as if in a dream” (時人見此一株華，如夢相似), as recorded in the *Recorded Sayings of Chan Master Dahui Pujue*.
The flower brings the vast claim down to an immediate meeting: this color, this seeing, this person, now. “Like a dream” should not be flattened into “the flower is unreal.” In a dream, things appear vividly, yet not in the independent way we suppose. Likewise, the seen flower is inseparable from light, eye, attention, memory, language, season, soil, and the entire situation of seeing. But Dahui also refuses to let us convert Nanquan’s gesture into a tidy theory. He warns that if one looks merely “on the level of principle” (若向理上看), one has not touched the living point. To repeat “everything is one” while remaining enclosed in self-protection is to possess the sentence and miss the flower.
Here we can locate 同根 within the path of liberation. Buddhist practice begins from suffering and the clinging that sustains it. Clinging depends upon taking “I,” “mine,” and “what confronts me” as solid, independently established poles. The insight of one root undermines that enclosure. But intellectual assent is only an opening. Ethical discipline reduces the conduct that continually rebuilds separation; meditative stability allows experience to be met without immediate grasping and rejection; wisdom sees that neither self nor phenomena stand by themselves. In Chan, this wisdom must become 大用現前 (*dàyòng xiànqián*, “the great functioning manifest before one”): responsiveness in ordinary circumstances, without leaving behind the trace of a spiritual identity.
Thus one root is not the terminus of a metaphysical argument. It is a gate through which the defended self may cease making a home out of separation.
A walkthrough in ordinary life
Imagine an evening commute after an exhausting day.
You are standing in a crowded train. Someone is watching a video without headphones. A message from your manager arrives: “Can you revise this tonight?” At nearly the same moment, your partner texts, “You haven’t really listened to me all week.” Your body tightens. The mind rapidly assembles a world: *noise attacking me, work exploiting me, another person demanding from me, and me trapped in the middle*.
Begin with the scope of “all phenomena share one root.” The teaching does not ask you to ignore the noise, deny your fatigue, or pretend that the manager’s request is reasonable. It asks you to notice what the defensive story omits.
Your fatigue is not a private object generated by an isolated self. It includes lost sleep, workplace expectations, food, hormones, previous conversations, financial pressures, and the train’s heat. The loud video includes a device, an attention economy, someone else’s habits, perhaps their loneliness or simple carelessness. Your manager’s message comes through an organization with deadlines and incentives. Your partner’s complaint arises within a relationship partly shaped by your own recent absence. Each event is distinct, but none is rootless.
This is the first correction: “one root” does not map only onto living beings, only onto human empathy, or only onto pleasant interconnection. The phone, the train, the employment system, bodily tension, resentment, and the wish for quiet are also among the “ten thousand dharmas.” If we include only what inspires tenderness, we have reduced the teaching to a mood.
Now consider “its measure equals space.” Your attention has contracted around a small center called *me under attack*. Without suppressing that feeling, let awareness include the soles of your feet, the whole carriage, sounds near and far, the people going home, and the open field in which irritation appears. This does not prove a metaphysical claim. It is a practical loosening of the boundary that makes one sensation feel like the total truth.
Next comes “do not divide this and that amid conditions.” The easiest mistake would be to interpret this as: *There is no difference between me and my manager, so I must say yes.* That is precisely wrong. One root does not erase conditions. You can distinguish exhaustion from capacity, consent from coercion, and an emergency from poor planning. What falls away, even briefly, is the need to turn a practical conflict into two absolute identities: innocent me and evil other.
From there, essence and function must remain together. If “one root” results only in a serene inner feeling, it has become inert. Its function might be a clear reply: “I can review the urgent section tonight, but the full revision will need to wait until tomorrow.” It might be putting the phone away and telling your partner, “You’re right that I’ve been absent. I’m depleted now, but I want to give this proper attention when I get home.” It might be politely asking the passenger to lower the volume—or deciding that this particular confrontation would be unhelpful.
No single response is mechanically dictated by the doctrine. “One root” is not an algorithm for producing identical behavior. Conditions differ. The test is whether wisdom and responsiveness operate together: less fixation on defending a separate self, more precision about what the whole situation requires.
Now look at the phone as Nanquan asks us to look at the flower. Before the manager’s message becomes “my ruined evening,” there are colored marks on glass, visual recognition, bodily contraction, remembered history, and an anticipated future. The message is effective—it may alter your evening—but the solid world it seems instantly to contain is assembled through conditions “like a dream.” “Dreamlike” does not mean consequence-free. A dream can terrify the dreamer; a message can contribute to burnout. It means that what appears does not exist in the fixed, self-contained form projected upon it.
Algorithms offer a limited contemporary analogy. A recommendation feed is not simply “out there”; what appears depends on prior clicks, model design, commercial objectives, other users, and your present attention. Yet Buddhist insight should not be equated with a computational account. An algorithmic explanation concerns engineered causal processes and can be empirically investigated. 同根 addresses the lived and liberating insight that subject and object cannot be secured as independent essences. Computer science neither proves nor disproves that realization.
By the time you leave the train, nothing magical may have happened. You are still tired. The work remains. Your relationship still needs care. But the suffering has changed texture: instead of one besieged entity surrounded by alien forces, there is a field of conditions in which a response is possible. That shift—from enclosure to unobstructed participation—is where the teaching begins to become practice.
Why contemporary people need it
Contemporary life repeatedly trains us to experience ourselves as separate units competing for attention, status, security, and control. Digital systems construct individualized feeds; workplaces measure individual output; consumer culture converts identity into preferences; public discourse rewards the quickest division into camps. Even self-care can become the maintenance program of an embattled private self.
同根 does not deny individuality. It challenges isolation as the final truth of individuality.
This matters first because isolation magnifies suffering. When every discomfort is interpreted as something happening to a self that must independently master it, fatigue becomes personal failure, disagreement becomes existential threat, and dependence becomes shame. Seeing shared rootedness restores the hidden conditions. It does not eliminate responsibility; it makes responsibility more intelligent. You are responsible for your conduct, but you are not the sole author of every condition from which that conduct emerges.
Second, it deepens compassion without requiring sentimentality. If the myriad things are “one body,” another’s suffering is not merely remote information. When one hand removes a thorn from the other, it does not congratulate itself for altruism. Yet the analogy must be handled carefully: compassion does not authorize you to absorb another person’s choices, remain in abuse, or abolish boundaries. A healthy boundary can itself be the functioning of the whole—preventing harm from circulating further.
Third, it offers an ecological correction. Air, water, soil, microbes, food systems, and climate are not scenery surrounding an autonomous human subject. They participate in what a human body is from moment to moment. “One body” can therefore disclose why environmental harm is not merely damage to an external resource. Still, the Chan teaching should not be reduced to environmental ethics. Its range is wider: it interrogates the very structure by which a supposedly independent subject confronts a supposedly external world.
Fourth, it changes the meaning of freedom. Ordinary freedom is often imagined as exemption from dependence: no one constrains me, I owe nothing, I can choose without interference. But such freedom is impossible for a conditioned being. Chan freedom is closer to unobstructed functioning within conditions. Because there is no sealed self to defend at every instant, one can respond more fully. Hongzhi calls this “the great functioning manifest before one” and speaks of “great functioning in each and every thing, leaving no trace” (頭頭大用了無痕). Freedom is not departure from the world; it is intimacy with the situation without bondage to appropriation.
Finally, 同根 protects spiritual practice from becoming a private refuge. Meditation can be used to build a quiet interior fortress: *the world is chaotic, but I will preserve my state*. The teaching breaks that arrangement. If stillness and activity are not two, insight must survive email, childcare, illness, conflict, cooking, and repair. After practice, one returns to sit on the bed while “autumn sky joins the water at moonlit dusk”—an image in Hongzhi’s record of natural ease. Nothing needs to be advertised. The fruit is visible in how one meets what comes.
This is its place in liberation: not merely to replace “many” with “one,” but to release the grasping that turns both “many” and “one” into positions. When separation is not absolutized, greed loses some of its logic, hatred loses its wholly alien enemy, and delusion loses its imaginary observer standing outside life. The root is realized as functioning, and functioning becomes compassion, restraint, clarity, and ordinary responsiveness.
Common misreadings and clarifications
1. “One root means everything is literally the same.”
No. A child and an adult, care and cruelty, medicine and poison remain distinguishable. Causes have different effects, and actions carry different ethical weight. 同根 denies absolute separateness, not conditioned difference. Unity without difference becomes a featureless monism; difference without unity becomes fragmentation. Chan refuses both extremes.
2. “The root is a cosmic substance or universal Self.”
That interpretation imports more than the expression itself warrants. Chan language such as “one root,” “one source,” and “one body” points beyond fragmentation, but it should not automatically be turned into an eternal entity behind phenomena. Hongzhi’s language—“utter openness without a trace”—actively frustrates the attempt to grasp the root as a thing. If it becomes something you can picture, possess, or stand apart from, “that is not such a form” (不是恁麼形像).
3. “Because all is one, personal boundaries and moral judgments are delusions.”
This is spiritually dangerous. Functional distinctions are indispensable. Recognizing non-separation may require firmer boundaries, truthful speech, or intervention against harm. “Do not divide this from that” targets reified opposition; it does not prohibit discernment. Compassion without wisdom becomes enabling, while wisdom without compassion becomes abstraction.
4. “One body means I should feel everyone else’s emotions.”
Not necessarily. Emotional contagion is not realization. You may be deeply interconnected and still misunderstand another person. Their experience is not yours to appropriate. Shared rootedness supports careful listening precisely because it does not reduce the other to a projection of oneself.
5. “Dreamlike means unreal, so nothing matters.”
Nanquan’s flower is present enough to be pointed to. Dreamlike appearance is vivid and consequential, but it lacks the fixed independence we project upon it. Emptiness of independent essence is not absence of appearance or causality. Indeed, because events arise through conditions, conduct matters: changing a condition can change what follows.
6. “Understanding the philosophy is the realization.”
Dahui’s severity is directed especially at this mistake. He refuses to let “Heaven and earth share one root with me” settle into an elegant view held by an unchanged self. If the phrase becomes an opinion you defend, it has produced a new wall. Nanquan points to one flower: Can this seeing occur before the habitual machinery of possession and opposition closes around it? Can the insight function when someone disappoints you?
7. “One root is an extraordinary mystical state.”
It may be accompanied by profound experience, but Chan repeatedly returns it to ordinary functioning. Eating, answering, resting, refusing, caring, and seeing a flower are not inferior expressions of the teaching. What matters is whether activity proceeds with less obstruction and leaves less self-congratulatory trace. A dramatic experience can still be appropriated as “my attainment”; an unremarkable act of honest care may express the root more completely.
8. “Interdependence in science proves 同根.”
Scientific accounts can provide illuminating comparisons: organisms depend on ecosystems; cognition depends on bodily and environmental processes; networked systems produce effects no isolated component explains. But these findings remain specific, revisable inquiries with unresolved questions. They do not constitute proof of a Chan realization, and Chan language should not be presented as ancient neuroscience. At most, contemporary knowledge can make the fantasy of total independence harder to sustain.
The final difficulty is subtle. “All things are one” can become another conceptual shelter. Chan presses further: before you establish either oneness or separation, what is this flower, this sound, this person asking? The point is not to recite a universal answer. It is to meet the particular so completely that neither the particular nor the whole is excluded.
Then “one root” ceases to be a beautiful sentence about the universe. It becomes the way the hand releases what it was clutching, the way a boundary is spoken without hatred, the way another person is no longer merely an object in one’s private story. Heaven and earth have not newly been joined. What relaxes is the habit of standing apart.