A specific sensation shows up at certain stages, and it has a precise texture.
"This coolness, which feels like the vapor from dry ice, can originate from the bottom of the feet."1
Dry ice vapour is an exact comparison and worth holding: not cold water, not a breeze, not chill. A dense, visible-seeming, low-lying vapour that pours rather than blows — cool, but with body to it.
It arrives in the middle of the transformations from jing to chi,2 and it is felt "within and along the surface of the body," appearing intermittently around the time the saliva turns sweet.5
Which places it alongside the other markers of that phase rather than as an isolated event. See The Garden Is the Crown Chakra.
The direction is the diagnostic part, and it carries a claim about quality.
"It can proceed upwards starting from below, or descend starting at the head… the stage of emptiness reached when it ascends from below is usually more long lasting and more profound than stages of cessation experienced after one feels the chi in the head."1
Two directions, two grades of result:
Ascending from the feet → emptiness that is more lasting and more profound.
Descending from the head → cessation that is shallower and shorter.
Which is a rare thing in this material: a self-check with a stated ranking attached. You can notice which way the coolness went and draw a conclusion about the state that follows it.
And it fits the general rule about where cultivation energy is supposed to start: energies "always start from below, rising upwards and then streaming downwards," explicitly not in the head.3
So the ascending version is the one that follows the proper route. The head-first version is real and is second-best, which is worth knowing before you get one and conclude you have arrived somewhere.
The feet are named repeatedly as the hard part, and this marker is where that pays off.
They are "extremely hard to open," and the full circulations can only begin once the foot channels do.4
Which explains the ranking. A coolness that starts at the soles is evidence the hardest channels have opened — the ones furthest from where attention naturally goes, and the ones most people never work. A coolness that starts in the head is evidence of head activity only, which is cheaper to produce and tells you less.
Which is also the practical argument for whole-body method and for deliberately covering the feet. See The Turtle Straining From Its Shell.
So the direction of the coolness is, indirectly, a readout on how thorough your coverage has been — and that is the most useful thing on this page.
An analogy is offered for the mechanism, and it is unusually concrete.
Ancient buildings were cooled by letting running streams of water evaporate inside them — and that process is put forward as something that "may serve to explain some of this feeling of coolness."1
Evaporation cools. Something passing from one state to another, and the transition itself producing the drop in temperature.
Which maps onto what is claimed to be happening: the transformations of jing to chi.2 A denser substance converting to a subtler one, with the conversion producing the sensation.
May serve to explain is the hedge and it is the author's own. Nothing stronger is claimed for the mechanism.
But it does explain a puzzle about the sensation — why coolness accompanies a process otherwise described as universally warm. Heat is the constant of every stage in this sequence. If the coolness is an artefact of conversion rather than an absence of heat, both can be true at once. See The Golden Honey.
The same phenomenon carries two names, and they emphasise different aspects.
Confucian — ching an. Lightness and peace, described as a Springtime feeling.5
Tibetan — pliancy. The physical suppleness that grows over time in all successful cultivators.5
Which are not the same emphasis. Lightness and peace is a mood; pliancy is a property of tissue. And the coolness sits between them as the sensation that accompanies both.
The connection to pliancy runs through the warming material: heating the channels so the bodhicitta can melt means "becoming more pliant, flexible and softer."6 See The Abhisheka Is a Somatic Event.
And the Labors do not mention it.5 Which is worth recording: this is a marker with two traditional names and no place in the decoded sequence — one of the few pieces of the phenomenology that arrives without a Greek counterpart.
Note where it starts. Feet or head. That is the single most useful observation available about this sensation, and it takes no effort.
Expect it intermittently rather than continuously — it appears and goes, around the same period as the sweetness in the saliva.
Don't chase the ascending version. You cannot choose which direction it comes from; it follows the state of the channels, and the channels follow years of coverage. Working the feet is how you influence it, and that happens long beforehand.
Don't grade yourself harshly on getting the head version. It is a real stage marker, just a shallower one. See Gong Fu Is the Signpost, Not the Road.
And treat the quiet that follows it as the actual event. The coolness is the accompaniment; the cessation or emptiness it comes with is what the practice is for.
There is a second downward-moving sensation in this material, and confusing the two would be easy.
The baptismal descent: chi rises up the du-mai to the crown and then streams downwards "like water poured from a vase," felt mostly down the front, laying "a coating an eighth to a quarter inch thick," and no longer noticed after a few days.8
The coolness: vapour-like, dry-ice textured, intermittent, and able to travel in either direction.
Three differences that separate them cleanly:
Texture. Poured liquid with thickness, versus vapour.
Persistence. The descent settles as a coating and then fades permanently; the coolness comes and goes.
And direction. The descent only goes down, by definition. The coolness does both, and the direction is what it tells you.
Also distinct from snow imagery, which denotes emptiness or mental purity by being white — and is explicitly not this: "while there are many cultivation stages where the chi feels like a cool vapor, which can arise from the feet or the head, this is not what is being referenced here."7
The coolness is tied to one specific transformation, and it is named the same way each time it appears.
It arrives "due to the opening of chi channels and the transformations of jing to chi,"2 and again at the sweet-saliva stage "due to the transformations of jing to chi."5
Jing to chi is the first of the conversions in the Taoist scheme — the dense generative substance converting to the subtler energy — and it is the stage the early channel work is largely about.
Which does two things for placing this marker.
It dates the phenomenon. Coolness belongs to the early and middle stretch, alongside the sweet saliva and the initial channel openings, not to the late crown work.
And it explains why the sensation is a conversion artefact rather than a temperature. Something is changing state. On the evaporation analogy, the change of state is what produces the cool — which would make the coolness a direct report on the conversion rate rather than on anything being cold.
The full descriptive scheme is pointed elsewhere for detail: the jing-to-chi progression is "fully explained within Tao and Longevity, Working Toward Enlightenment and To Realize Enlightenment by Nan Huai-chin."
Evidence. [PRACTITIONER SOURCE]. 🚩 SINGLE SOURCE 🚩 SECONDARY WITHOUT PRIMARY — the Confucian and Tibetan terms are named without texts. [SPECULATIVE] on the evaporation mechanism, which is offered as a maybe.
Tension — cool, in a hot process. Warmth is stated to accompany every transformation, and this is a coolness accompanying transformation. The evaporation analogy reconciles them and is explicitly not asserted as the explanation.
Tension — a graded marker among ungraded phenomena. Almost every other phenomenon here is to be ignored; this one comes with a quality ranking attached and an implied instruction to notice.
Open question — why is it absent from the Labors? A marker with two traditional names, present in the phenomenology, and no place in the decoded sequence.
Open question — can it be produced from the feet deliberately? Given that the ascending version is better, and the feet are named as the hard region, the obvious question is whether foot-focused work brings it on. Nothing addresses it.
Two ways this sits in the material, and they pull differently.
As a marker worth reading. Direction indicates depth, feet indicate coverage, and the sensation is described precisely enough to be matched against.
And as one more phenomenon. The standing instruction on everything felt at these stages is to note it and let it go without attaching significance — and a practitioner attending to which way their coolness travelled is doing the opposite of that.
Both are defensible and the material does not choose. The reconciliation available: use it once, in passing, as a readout — and don't wait for it. Which is roughly how every other physical marker in the sequence is handled.
Felt Sense and Somatic Awareness — psychology.
A felt sense is a whole, vague, bodily-located quality that carries information the person cannot yet articulate — and the work consists of staying with it until a word or image arrives that fits, at which point something in the body shifts.
Two properties bear on how to use this marker.
The bodily quality is primary; the description is generated to match it. Which is why people describe the same felt quality with wildly different images, and why the fit is recognisable to the person even when the image is idiosyncratic.
And the useful information is in the location and the movement, not in the descriptor. Where it sits, whether it moves, which direction — these are the features that carry content, and they are the features people skip past on the way to naming the sensation.
Which is precisely why dry ice vapour is the wrong thing to match against and starts at the soles is the right thing. The texture is one person's descriptor for a quality their own vocabulary supplied. Yours may be mist, or menthol, or nothing you have a word for — and none of that variation means you are having a different experience.
The direction is the part that transfers. It is not a description; it is a fact about where the quality began and where it went, and it would be reported identically by anyone regardless of what they called the sensation.
Practical form: when matching a somatic marker against someone else's account, discard the adjectives and keep the geography — origin, path, extent and timing survive translation between bodies, and the texture words never do.
What the source leaves undetermined is whether the direction causes the depth or merely reports it.
The claim is that ascending coolness accompanies a more profound and lasting emptiness than descending coolness does. Which admits two readings.
Reporting: the feet being open is what produces the deeper state, and the coolness's direction is a side effect of the same fact. Under this the marker is diagnostic and nothing more — you cannot improve the state by influencing the sensation.
Causing: something about the upward movement itself — travelling the full length, arriving after passing through everything — is what produces the depth. Under this, the route matters and not just the openness.
The difference decides whether there is anything to do. If it merely reports, the only intervention is years of foot and whole-body work. If the route contributes, then the ascending version is worth cultivating conditions for — and nothing anywhere says how, or whether that is even coherent.