From a martial perspective, to Song the opponent is to negate their power at its source — not by overpowering it, but by dissolving the structure that allows it to exist. Every Jìn (勁), no matter how refined, depends on a foundation of tension, direction, and segmentation. The Song practitioner disarms all three simultaneously by offering no opposition to meet, no surface to strike, and no fixed center to press against. There are, however, many ways to bring about this undoing — some through emptiness, others through control — yet all rely on the same internal state of release. 

In this encounter, Song is the art of undoing. It is not an act of defiance, but of deep compliance — a surrender so complete that it overturns the logic of force itself. When you do not resist, their strength finds no object; when you do not push, their energy cannot complete its path. The opponent’s Lì (力) turns inward, uncoiling back through their own chain of tension, and they collapse through the undoing of their own intent.

As noted by Sifu Mark Rasmus, the art of undoing an opponent relies not on opposing force but on extending internal release into the other’s structure, creating a field in which their tension naturally unravels. 

Yet this dissolution can appear in two distinct modes — the Empty Song (虛鬆) and the Commanding Song (實鬆) — each embodying a different face of the same principle.

Undoing, Not Attacking

Every act of strength relies on internal compression — a pattern of muscular binding that generates mechanical leverage. The Song body contains none of this. It receives, yields, and softly absorbs.
When the opponent’s energy meets such an open structure, there is no “impact”; their power simply returns home. Their arm stiffens, their spine tightens, and the very mechanism they relied upon to project force begins to fail. You do not strike them — you let their own effort untie them.

This is the work of the Empty Song (虛鬆). The practitioner offers pure softness — a tranquil void in which the opponent’s effort unravels. The emptiness becomes a mirror, revealing their internal tension and returning it to them. Their collapse feels voluntary, as if they had exhaled their strength away.

The Commanding Song (實鬆) takes the same principle and expresses it with direction. By sensing and entering the opponent’s Jìn Lù (勁路), the practitioner follows the energy to its root. Without breaking alignment or adding force, they subtly lead the line of tension until it overextends and collapses under its own pressure.
Here, you do not yield completely — you guide the uncoiling. The result feels inevitable: their own power line becomes the path of their undoing.

Uncoiling the Body

To Song the opponent is to enter their fascia and joints with seamless continuity. Through contact, your structure harmonizes with theirs; the unwinding begins from within them, not upon them.
The hips lose their compression, the shoulders empty, the spine releases. What was once coiled and ready becomes soft and formless. In that instant, their internal alignment ceases to function — the body’s stored potential collapses into neutrality.

In the Empty Song, this uncoiling occurs by resonance. Your own relaxed tissue and coherent structure invite their fascia to harmonize and unwind. The opponent feels as if their body were melting, their joints quietly sighing open.
In the Commanding Song, the same outcome is achieved through precision — a subtle engagement of the Jìn Lù that presses just enough to awaken their internal contraction, then leads it through a spiral until it can no longer hold. Their system releases because the only possible continuation of the line is surrender.

True Song acts like an internal exhale that passes through two bodies as one. It is the uncoiling of force, not its redirection.

Collapse Through Peace

The result is a fall without violence. The opponent experiences a wave of stillness — an inward quiet that renders resistance impossible. Their structure softens, their nervous system releases, and what remains is calm.
This collapse is not defeat but resolution. They may smile, laugh, or feel a curious tranquility as they fall, as if their body had been waiting to rest all along.

The Empty Song brings about this peace through complete yielding: the opponent falls into your silence.
The Commanding Song brings it through guidance: you carry their tension to its natural conclusion — rest.
In both cases, the collapse is peaceful because the practitioner never imposes conflict. The body of the opponent simply returns to stillness, following its own path home.

“To Song an opponent is to return them to stillness through their own motion — to transform struggle into release.”

This is the highest form of martial negation: to win without opposition, to prevail through the restoration of peace.
In Taijiquan, true victory is not measured by dominance, but by how completely conflict ceases to exist.