Chapter Five: Yang Sprouting Within Supreme Yin — The Mystery of Tigers Mating and Lychee Grass Emerging

I. Within Supreme Yin, How Can Yang Sprout$32

The zi month in which Major Snow falls is the time of yin qi's greatest power, yet also the inception of yang qi's imminent sprouting. This seemingly contradictory proposition — "yang sprouts within supreme yin" — is the most profound mystery of the entire Major Snow solar term, indeed of the entire Chinese cosmological vision. This chapter will elucidate this mystery through the second and third pentads of Major Snow's three phenological signs: "tigers begin to mate" and "lychee grass pushes forth."

Why can yang sprout within supreme yin$33 We must begin with the fundamental principle of the Book of Changes. The core conviction of the Zhou Yi is that yin and yang transform into each other: when things reach their extreme, they reverse. When yang reaches its extreme, yin is born; when yin reaches its extreme, yang is born. The winter solstice is the annual extreme of yin qi, and it is precisely at this extreme that yang qi begins its renewal. Major Snow, immediately adjacent to the solstice, already stands at the critical threshold where yin is about to peak and yang is about to stir. Though yin qi continues to deepen toward its extreme, the thread of yang about to sprout is already quietly gestating in the depths of supreme yin.

How did the ancients discover this$34 They possessed no thermometers, no instruments for measuring sunlight, yet through the most meticulous and attentive observation of all things, they detected the earliest harbingers of yang qi stirring within supreme yin. These harbingers are "tigers begin to mate" and "lychee grass pushes forth." This is the supreme manifestation of the ancients' spirit of "investigating things to extend knowledge" (ge wu zhi zhi): from the mating of tigers and the sprouting of grass — these minute vital phenomena — they read the great tidings of yang qi's renewal between Heaven and Earth.

II. "Tigers Begin to Mate": The Most Yang Beast Stirs at the Touch of Faint Yang

The second pentad of Major Snow is "tigers begin to mate" — tigers commence their mating season.

Why tigers$35 Why in the coldest season of Major Snow$36 This is no idle phenological notation but contains extremely deep philosophical significance.

The tiger, in the ancients' conception, was the beast of supreme yang vigor, ferocity, and kingship among animals. The Wenyan commentary on the Qian hexagram states: "Clouds follow the dragon; winds follow the tiger." The tiger corresponds to wind, and wind is a manifestation of yang qi in motion. The Shuowen Jiezi glosses hu (tiger): "The tiger is the lord of mountain beasts." The tiger is the monarch of the forests, the incarnation of strength and masculine vigor.

Why, then, does this most yang, most vigorous of beasts begin to mate precisely in the most yin, most frigid season of Major Snow$37 The answer is: "stirred by faint yang." Mating is an act of life's propagation and vitality's initiation — essentially a mobilization of yang qi and life force. The tiger, as the most yang-sensitive of all yang-vigorous beasts, is able to perceive the earliest stirring of that faint thread of yang qi within supreme yin before all other creatures. While the vast majority of life still sleeps in winter storage, the tiger has already sensed the first tidings of yang's renewal and begins to mate.

This is the deep significance of "tigers begin to mate": it is the earliest and most powerful harbinger of "yang qi already sprouting within supreme yin." The tiger mates not because the weather has warmed (it is still growing colder, heading toward the solstice's extreme cold) but because it has sensed that invisible, intangible, yet genuinely present thread of renascent yang. This corresponds precisely to the Return hexagram's image of "a single yang returning" in the zi month — beneath five yin lines, a single yang stirs; amid the vast snowfall, the tiger has already sensed yang and begun to mate.

III. "Lychee Grass Pushes Forth": A Plant Sprouts in Response to Yang Qi

The third pentad of Major Snow is "lychee grass pushes forth" (li ting chu) — the lychee grass (also called ma lin, or iris) sprouts new shoots in response to the stirring of yang qi.

"Lychee grass" is a herbaceous plant resembling rushes but smaller, whose roots can be used to make brushes. During Major Snow's third pentad, this grass puts forth new sprouts amid ice and snow.

This is another miracle of "yang sprouting within supreme yin." Amid the desolation of withered trees and dead grass, in the frozen and sealed earth of deep winter, the vast majority of plants have ceased growth and withdrawn into their roots. Yet lychee grass sprouts at just this time — like the tiger, it has sensed that thread of renascent yang within supreme yin and is the first to germinate.

If "tigers begin to mate" reveals "yang sprouting within supreme yin" from the animal kingdom, then "lychee grass pushes forth" confirms the same truth from the plant kingdom. One animal, one plant; one vigorous, one gentle; one responding through mating, one through germination — together they compose the complete picture of Major Snow's final two pentads: "yang qi about to sprout within supreme yin."

IV. Tiger, Lychee Grass, and the Return Hexagram: A Tripartite Resonance

Now let us connect "tigers begin to mate" and "lychee grass pushes forth" with the Return hexagram of the zi month.

The Return hexagram (Fu, ䷗) has the trigram Zhen (Thunder, a single yang below) beneath the trigram Kun (Earth, pure yin above): five yin lines, with a single yang line newly born at the bottom. This single yang line is the yang qi that has just begun to stir within supreme yin. "Tigers begin to mate" and "lychee grass pushes forth" are the living, concrete manifestations of this single yang line in the natural world — the tiger senses this yang and mates; the lychee grass senses it and sprouts. The hexagram image is an abstract symbol; the phenological signs are concrete phenomena; yet both point to the same truth of Heaven and Earth: at the extreme of yin, a single yang returns.

This correspondence between hexagram image and phenology is the most exquisite feature of the Chinese cosmological vision. The ancients did not conjure the Return hexagram from thin air; they distilled and abstracted the principle of "a single yang returning" from real natural phenomena like the tiger's mating and the lychee grass's sprouting. In turn, the Return hexagram provided a unified, profound interpretive framework for these scattered observations. Celestial phenomena, phenological signs, and hexagram principles mutually corroborate one another in seamless unity — this is the most concrete, most vivid embodiment of the "unity of Heaven and humanity" cosmology.

The final two pentads of Major Snow tell us: do not be deceived by the surface cold and deathly stillness. Beneath the white-mantled snowfields, amid the seemingly soundless Heaven and Earth, life's power has never ceased. The tiger is mating, the lychee grass is sprouting, yang qi is stirring, and the heart of Heaven and Earth is awakening. Major Snow is the season of hope at its most profound and most unwavering.