The boundary between self and world is rooted in the body. It is built from signals so familiar they go unnoticed until we attend to them.
Close your eyes and hold out your hand. How do you know where it is?
Proprioception provides you with that information. It is the body’s sensing of its own shape and position, enabling you to reach for a cup or bring your fingertips together without looking. Much of it operates below conscious awareness, but some surfaces into direct experience.
Waving your hand with eyes closed makes proprioception most evident. You feel your hand moving from left to right, but also see the movement inwardly.
Proprioception is driven by signals originating from muscles, tendons, and joints. The skin contributes as well, relaying a steady hum of information about the body’s outermost layer. We feel this as a faint tingling on the skin’s surface, so fine in texture that it can simply register as pressure.
From this baseline sensory noise, the brain constructs a felt image of the body’s outer boundary, a three-dimensional representation that persists in the background of our awareness.
Representations have subtle qualities, which is why they’re easy to overlook. We navigate daily life with our eyes open, flooding the brain with visual information that drowns out quieter signals. Closing the eyes helps bring these representations into focus.
Your hand is then represented in front of you as a hazy form, its contours barely distinguishable from the surrounding darkness. It is transparent to whatever is behind, yet visible to the mind’s eye. If awareness left a shadow, it would look like this.
Keeping your eyes closed, rest your hand down and imagine holding it out. Then do so physically. The two experiences share qualities: both are appearances without a visually perceived object, but they differ in how fleeting they are. Mental images fade as attention moves on. The hand representation, by contrast, remains present even without trying to maintain it.
Keeping your eyes closed, rest your hand down and imagine holding it out. Then do so physically. The two experiences share qualities: both are appearances without a visually perceived object, but they differ in how fleeting they are. Mental images fade as attention moves on. The hand representation, by contrast, remains present even without trying to maintain it—something that mental imagery cannot replicate.
Place an object in front of you and rest your hand next to it. With your eyes closed, turn your head to the left; your hand and the object now appear to the right. The brain represents the body and its environment within the same head-centric spatial map, organizing them into an approximate field of locations and directions. Representations appear larger or smaller depending on the brain’s estimation of how far the physical object is from the head.
Your hand appeared to the right, but since the sensation was unchanged, its directional shift came from the reorientation of the spatial map. It was the map that told you where your hand was, not the sensation alone.
The body is the point around which experience is spatially structured. It is also the only entity whose movements are registered as arising from within rather than occurring in the environment. We don’t merely encounter the body as an object in the world; it is what does the encountering.
Positioned at the center of the spatial map, the body representation is continuously refreshed by a stream of sensory input. When visual information is absent, objects in the environment are represented with less precision, their locations instead inferred from memory. The body representation is anchored more firmly than anything else in the map. This makes it the felt location of the self.
When the body representation becomes more prominent, the felt location of the self sharpens into a divide. We find ourselves here, and the world appears out there.
Look at an object and draw your attention to its distance. The experience presents itself as space between you and what you see. When you close your eyes, the gap remains: the object representation persists at that same distance. What you saw with eyes open was placed there by the spatial map. It is the sense of space, not vision itself, that makes the world appear as something outside us.
Throughout evolutionary history, a clear boundary distinction has been critical to survival. When facing a threat, an organism must have an acute sense of what is self and what is other, of where the body ends and danger begins. Without it, neither defense nor escape is possible.
The mechanism nature settled on is contraction: when the threat-response system is activated, muscles tense in defensive bracing. Increased proprioceptive signals generated by that contraction, interpreted through the brain’s threat state, heighten the representation of the body’s boundary. The self-other distinction crystallizes exactly when it is most needed.
Not all muscle tensing has this effect. Exercising increases proprioceptive signals without activating the threat-response system. What distinguishes defensive bracing from ordinary muscle tension is the brain’s threat state. This is self-contraction.
Self-contraction manifests in our lived experience. Under stress, the body tends to tighten in the jaw, shoulders, and core, the postural muscles most involved in defensive readiness. The body reacts to a perceived threat, whether physical or not: an uncomfortable social situation, the fear of being judged, or the pain that accompanies unwanted thoughts.
From early childhood, we learn to guard against disapproval and suppress spontaneous expression, layering tension as the price of belonging. This pattern has biological roots, but it is reinforced socially, modeled by parents, peers, and the culture at large. By adulthood, self-contraction has become so familiar it passes for normal.
Where ancestral threats could be resolved through fight, flight, or freeze, modern stressors tend to be abstract and open-ended. Difficult life circumstances do not yield to a single decisive action, and the threat-response system has no clear signal to stand down. The bracing persists even when there is nothing concrete to protect against.
Self-contraction recurs frequently enough throughout the day that it comes to feel like the natural resting state of the body. It goes unnoticed because it is rarely absent for long. Sleep offers genuine respite, but the pattern often reasserts itself with waking.
When painful thoughts arise, the body contracts as though under attack. To the brain, this is evidence of lingering danger. We find ourselves ruminating—the brain circling a problem no action can resolve—only to reinforce the stress and contraction. The thoughts never come to rest.
The accumulated tension produces a characteristic felt quality: a knot in the chest and stomach, a pressure in the solar plexus. This feeling becomes inseparable from the sense of self.
Over time, the cumulative effect of self-contraction is a chronically heightened body representation. We become bounded, isolated selves. The clearer the self-world boundary, the more palpable the sense of something finite within it, exposed to all that lies outside. In defending against vulnerability, we deepen it.
The loop sustains itself independently of the stressors that originally set it in motion. Because of this, self-contraction holds sway even in objectively safe circumstances.
Self-contraction is not, however, an inevitable feature of human experience. The pattern naturally loses its grip when we recognize it has outlived its evolutionary purpose. What stands in the way is not the releasing itself but unlearning the deeply ingrained instinct that makes contraction feel necessary in the first place.
What happens when self-contraction is released?
As defensive bracing subsides and proprioceptive signaling returns to baseline, the body representation gradually recedes. The hand, which previously stood out against the surrounding space, softens toward it.
With the boundary of the body losing salience, the contrast between hereness and out-there-ness fades. The sense of space diminishes with it, the body relinquishing its dominance as the center from which the world is projected. As the gap closes, objects appear less and less distanced.
Imagine your hand representation dissolving until it resembles the empty space beside it. As the figure-ground contrast disappears, hand and surrounding space become indistinguishable in experience.
What would happen if your entire body representation were to dissolve in the same way? Where would you find yourself?
Sensations would still exist, but not be represented anywhere in space. Thoughts would still arise, but without a bodily location to serve as their referent. With no body representation to anchor a here, the sense of being a bounded individual would have nothing left to rest on.
The spatial map is what underlies the perceptual separation between subject and object. Within it, the body representation is the scaffolding of our selfhood—the felt foundation upon which higher-order conceptions of self are built, but which requires no conception itself. Without this scaffolding, experience has no center.
This dissolution does not entail complete selflessness or functional collapse. In practice, proprioceptive signaling never goes to zero. What remains is a minimal body representation reduced to a prominence comparable to that of other objects. The felt sense of being located here dissolves not because the body disappears from experience but because it no longer stands out from anything else.
The sense of space diminishes to a minimum. Objects appear with vivid colors and sharp detail, but without the gap that normally positions them as distant. Perception feels intimate, as though there is no difference between what sees and what is seen.
This does not impair accurate interaction with objects because the brain retains full access to depth cues. Binocular disparity, relative size, and perspective all operate independently of the sense of space. The gap expresses felt separation, not the brain’s estimation of depth.
Contemplative traditions across cultures have long described states where the sense of separation has dissolved. At the heart of these traditions lies the concept of non-duality, the recognition that the boundary between self and world is not a fundamental feature of reality but a constructed one. What remains is experience without the separation of subject and object. These traditions see in this the source of inner peace.
This framework offers a mechanistic account of subject-object dissolution: the felt sense of being a separate individual is a bodily variable, modulated by self-contraction and body representation prominence. What contemplative traditions have approached through inquiry and practice, this framework traces to a physiological source that empirical investigation can address.
While the relationship between muscle tension and proprioceptive signaling is well established, the specific claim that self-contraction correlates with body representation prominence awaits empirical verification. The experiential changes are accessible to first-person observation, though capturing them through third-person measures remains an open question. How minimal body representation prominence relates to non-dual states reported in contemplative literature has yet to be rigorously examined.
But the starting point requires no apparatus—only the willingness to close your eyes and hold out your hand.