The Celestial Mechanism

The I Ching is a book about the Celestial Mechanism.

Although the words are very clear, yet they are also very vague. The shallow may take the I Ching to be a book of divination, but the profound consider it the secret of the Celestial Mechanism.
-- Lu Dongbin (9th c. Taoist master, introduction of The taoist I Ching)

The ancient maxim as above, so below attributed to Hermes Trismegistus (purported author of the Hermetic Corpus) refers to the idea that the principles of the macrocosmos universe are mirrored in the microcosmos man.

It is impossible to study man without studying the universe. Man is an image of the world. He was created by the same laws, which created the whole of the world. By knowing and understanding himself he will know and understand the whole world, all the laws that create and govern the world. And at the same time by studying the world and the laws that govern the world he will learn and understand the laws that govern him. -- Gurdjieff (20th c, Fourth Way teacher)

This idea is part of all esoteric traditions and plays an important part in the inner meaning of the I Ching and the 2nd century Taoist text Canton Qi (Triplex Unity)

The perfect man of old observed the ways of heaven, they grasped the actions of Heaven. Thence they borrowed the advance and retreat of the heavenly tokens and the movement of Yin and Yan; they constructed a model of the firing times for the elixir in order to inform people. In general Heaven and Earth are similar to a cauldron, while the sun and Moon represent the medicinal ingredients placed within. The Sun and Moon travel the breath between Heaven and Earth, coming and going, appearing and disappearing. These create firing times. -- Yuyan, 13th c. Taoist master (The Secret of Everlasting life ,Commentary on the CanTong Qi)

Because the Firing Times of controlling the human mind or lower self — the stripping away of mundane yin — and bringing out the Original Spirit or Higher self — creating pure yang — are symbolized in various movements of the heavenly bodies, it is also called the Celestial Mechanism.

But this celestial mechanism of practicing reversal in the midst of accord has a secret, which is communicated verbally and instructs the heart; one must seek the guidance of the true teacher, for it cannot be known through arbitrary guesswork. Although it is called reverse action, in fact it is action in accord with principle. It is called reversal because it goes contrary to the course of action of ordinary people. 

-- Liu Yiming (The Inner Teachings of Taoism)

These various cycles of heavenly bodies have different durations, but actually symbolize the same thing.

Whether the text talks about hours of the day, the days of the month, the months of the year or the four seasons, it is basically describing one and the same thing – the timing of the production of the Golden Elixir through the firing process.
 -- Richard Bertschinger, The Secret of Everlasting Life (a translation of the Canton Qi)

The Big dipper traveling around the North Star, the waxing and waning of the moon, also called the firing times of the lesser circuit of the sky, and the circulation of the sun, also called the firing times of the greater circuit of the sky, all symbolize the firing times. The times of the firing are represented by different trigrams and hexagrams.

The Big Dipper

Although my body is the body of an ape,
When young I mastered the paths of life and death.
I visited all the great teachers who taught me their Way
I took Heaven as my roof and the Earth as my furnace
And used both kinds of medicine to complete the sun and moon,
Taking from yin and yang, joining Fire and Water,
I relied entirely on the Dipper for success in my movements.
-- Journey to the West, Ch 70
The Head and the Handle (of The Dipper) are the necessities of the Way, they are the rope to manage all transformations. 

-- Wei Boyang (2nd c. Taoist master, Cantong Qi)

The Head (kui魁) refers to the four stars of the dipper, and Handle (bing 柄) to the last three stars of the Dipper. In ancient times man would navigate according to the position of the stars at night. The stars guided one to one`s destination. Internally this refers to the breaths of the firing process guiding one to one`s internal destination; the presence of the Original Spirit. A star is after all, a sun, and represents fire, which symbolizes the illumination of conscious awareness. The three stars of the dipper handle relate to the firing times to create the pureness of three yangs, the trigram Qian (Heaven) ☰, which is an abbreviation of the hexagram Qian (Heaven) ䷀ and are represented in the first six oxherding pictures. The four stars of the head relate to four immortals breaths and are represented in the last four oxherding pictures.

This immortal fourfold breath, is hidden in the original cavity of the spirit, behind the spot between the eyes.
-- Chao Pi Chen (20th c. Taoist master)

The Moon — The Lesser Circuit of the Sky

The inner development of the elixir and the timing of it`s firing are no different at all from the ebbing and the flowing of the phases of the moon. The six lines of the Heaven hexagram act as an image of the waxing and waning of the moon`s body. But it`s all metaphor. -- Yu Yan (The Secret of Everlasting life , Commentary on the Cantong Qi)

All esoteric traditions see the moon as a symbol for liberation.

There is an expression in the system, to create moon in oneself. It is a symbolical expression, and symbols in the form of diagrams or symbolical expressions are used for very definite purposes.
-- Ouspensky (20th c. Fourth Way teacher

As said above, the trigrams Fire (Sun) ☲ and Water (Moon) ☵ are not part of the firing process. The six trigrams that make up the firing times have a natural ebb and flow from one yang to three yangs and then returning from one yin to three yins. Fire and Water take charge of these six trigrams and are the medicine; yin and yang; the inhalation and exhalation of the breath; they are not part of the cycle of the moon. The crescent moon is symbolizes by the trigram Thunder and hexagram # 24 Return .

The crescent moon refers to the moon of the third day of the lunar calendar month, appearing as a hook of light in the direction of earth (southwest). That light curves upward, that is why it is called the crescent moon. What this crescent moon symbolizes in humans is a point of yang light shinning through the middle of extreme quiet. Among the trigrams it is thunder ☳. The point of yang light is nothing but the light of the mind of Tao. -- Liu Yiming, Commentary on Understanding Reality)

The Cycle of the Moon -- Wei Boyang (Cantong Qi - Triplex Unity)

Thunder ☳ comes forth as an inkling,
and the Yang Breath makes it start:
“Initial nine, submerged dragon.”

On the third day Thunder ☳ moves,
on the eighth, Lake ☱ is in action.
“Nine in the second place, appearing dragon”

On the fifteenth, virtue is attained
And the body of Heaven ☰ is achieved.
“Nine in the third place, at nightfall he is watchful,”
fearing that he might lose the magic charm.

When Wind ☴ takes control,
it firmly holds it in his hands.
“nine in fourth place, wavering flight”:

Mountain ☶ rules over arrest and advance,
On the twenty-third day,
it presides over the waning quarter.
“Nine in the fifth place, flying dragon”:
sitting in the throne of Heaven, it increases it`s delight.

On the thirtieth day, Earth ☷ inherits the charge,
Carrying and nourishing her children,
She is like a mother to all things in the world.
“Nine at the top, thriving dragon,”

The use of the dragon-nines flying to and fro,

are the compass and square of the Dao.
The Yang numbers are now completed.

The Cycle of the Moon symbolizes the creation of the Golden Elixir by using six trigrams. Each trigram is a step of the Firing Times going from one yang ䷗ to the pureness of six yangs, when the hexagram Qian (heaven)  ䷀ is reached.

Wei Boyang uses the six trigrams to illustrate the `firing times' of the Elixir, but he also matches them with the six lines of the hexagram Qian. Why does he do this? Because the Elixir is the most precious treasure of the purest Yang, and Qian (Heaven) is the hexagram of the purest Yang. 
 -- Yu Yan (The Secret of Everlasting life ,Commentary on the Cantong Qi)

Logically this does not make sense, since from the fourth trigram on, yang begins to decrease and returns to yin with the sixth hexagram. However, as Yuyan said above it is all metaphor. The symbols of inner alchemy have the same purpose as the koans of Zen-Buddhism, which is to bypass the logical mind and inspire and awaken the Original Spirit.

Taoist Alchemy is nothing but metaphors. It uses a special language that aims at disrupting ordinary thinking by tearing apart the hardened knots, the solid barriers. Eventually this language will soften the mind in exactly the same way as the body has been relaxed previously by the various techniques of respiration.
 -- Danyangzi (2nd patriarch of the Complete Reality school of Taoism)

The Sun — The Greater Circuit of the Sky

While the cycle of the moon uses the trigrams, the cycle of the sun uses the hexagrams to symbolize the creation of the Golden Elixir.

Ancient immortals used the term Gold Elixir as a metaphor of the essence of true consciousness...... Growing from one yang to gradually reach the pure wholeness of six yangs, growing from vague to clear, the Gold Elixir develops naturally. -- Liu Yiming 
(Inner Teachings of Taoism)

The Cycle of the Sun -- Wei Boyang (Canton Qi - Triplex Unity)

At the new moon`s light lies Return ䷗;
The Yang breath begins to spread through,
Going out and coming in without error.

At Overseeing ䷒, the furnace issues strips of light,
Opening the way for proper radiance.
Radiance and shine gradually advance.

Looking upward, it forms Tranquility ䷊.
The firm and the yielding both come to hold sway.
As Yin and Yang conjoin,
The small departs, the great approaches.

Gradually comes the turn of Great Strength ䷡.
Boldly standing at the gate to dawn.

At Parting ䷪ the time has come for Yin to move into retreat,
For Yang has risen and has come to the force.

Heaven ䷀ is strong, flourishing, and bright,
And lays itself over the four neighbourhoods.

Here, pure yang has been reached and the Golden Elixir is created. The verse then continues with six hexagrams (Meeting ䷫, Withdrawal ䷠, Obstruction ䷋,  Observation ䷓, Stripping Away ䷖ and Earth ䷁) showing the ascend of yin and descend of yang.

The honorable person is like the waxing of yang. The dishonorable person is like the waxing of yin. -- Sui Qing Tzu (19th c. Taoist master, Commentary on Cultivating Stillness)

These hexagrams represent mundane yin energy arising, pure yang energy being injured and consequently the loss of the Golden Elixir. When one observes this in oneself, one tries to interrupt this process and return to pure yang again. The end verse of this section is as follows:

There is a dark (hidden) secret, remote and slight, that separate they are yet joined together. -- Wei Boyang (Canton Qi - Triplex Unity)

Taoist master Shangyang comments on this:

In just these two lines is the most perfect and complete summary of what is meant here. Separate they are yet joined together meaning that the two objects Yin and Yang are 10,000 miles apart in their activity - but if they gain the old Yellow Woman to act as match-maker, although far from each other, they come very close together. And then the two materials respond in due measure, bearing as a seed ‘the primacy of yin and yang. -- Master Shangyang (The Secret of Everlasting life, Commentary on the CanTong Qi)

Now these twelve hexagrams are seen from a different perspective. The two groups of six hexagram (six hexagrams of advancing Yang and six of advancing Yin), if they gain the Yellow Woman, actually represent the inhalation and exhalation of the six yang breaths of the firing process.

The Sun and Moon travel the breath between Heaven and Earth, coming and going, appearing and disappearing. These create firing times. -- Yuyan (The Secret of Everlasting life, Commentary on the CanTong Qi)

The yang of Heaven and the Yin of Earth are like the opening and closing of a door….. Opening and closing, breathing out  and breathing in, are the door of the mysterious female, the root of Heaven and Earth. Here breathing out and breathing in do not refer to exhalation and inhalation through the nose, but rather to the opening and closing of the true breath, the inner pulse of life, the movement of energy and stillness of the spirit.  -- Li Dao Chun, the Book of Balance and Harmony p48

The first verse about the return of Yang said: The Yang breath begins to spread through. After one has reached the pureness of six yangs, meaning a pure state of conscious awareness, one does not want to return to yin intentionally. In fact, the hexagrams following #1 Heaven, Hexagram #44 Meeting, #33 withdrawal , #12 Obstruction, #20 Observation, #23 Stripping Away and #2 Earth, are all about how to ward off yin energy.

The gold elixir, once attained, is again lost, and it is one's own fault.
-- Liu Yiming (The Taoist I Ching, hexagram #44, commentary on the top line.

The Firing Process and the Celestial Mechanism are intentionally not completely explained.

Wei Boyang (the author of the Cantong Qi) never dared to reveal completely the dark (secret) workings of the natural world. -- Zhu Yanyu (The Secret of Everlasting life, Commentary on the Canton Qi)
It is not that the immortals and real people haven't spoken of the firing process, but what they say is not organized. If you do not meet an illumined teacher, who will indicate the order for you, you will not be able to know it. -- Liu Yiming (Commentary on Understanding Reality)

In the Taoist I Ching, Liu Yiming mentions about fourteen times that the firing process cannot be known on one`s own; one needs to find a genuine teacher.

The cycle of the sun takes twelve months; each hexagram is matched with a month. However, Taoist scriptures repeatedly speak of ten months of work, not twelve months.

Restoring the elixir takes place momentarily; refining the self requires ten months. -- Liu Yiming (The Inner Teaching of Taoism)
When it is said that the method of the gold elixir is complete in ten months, this is just a metaphor of pregnancy – it means that after the spiritual, embryo is solidified, it is necessary to ward of danger and gently nurture it until it is fully developed, without any lack; it does not mean there is a fixed period of ten months. -- Liu Yiming (The Inner Teaching of Taoism)

The Chinese use the lunar calender, where one month is four weeks, so a pregnancy is considerd to be ten months. The number ten is what is important here. All the symbolic cycles of the Firing Process come down to ten breaths.

In general, a year and a month are simply one and the same, a month and a day are simply one and the same, and a day and an hour are simply one and the same. The spectacle of a year appears within a whole month, the spectacle of a month appears within a whole day, the spectacle of a day appears within a whole hour. Any single hour contains within itself the ‘catch’ whereby the single yang returns. -- Yuyan (The Secret of Everlasting life, Commentary on the Canton Qi)

One needs to continue: The spectacle of an hour appears within a whole breath. Any single breath contains within itself the ‘catch’ whereby the single yang returns.

The firing process with its advanced and withdrawal, extraction and addition, increasing and decreasing, concentrates a year into a month, a month into a day, a day into an hour and an hour into one breath. -- Li Dao Chun (13th c. Taoist master, The Book of Balance and Harmony)

The Firing Process refers to six breaths of action and four breaths of non-action in which one bathes.

The secret of the elixir of life consists in using action in order to attain non-action. -- The Secret of the Golden Flower, Chapter 1
One who mounts the truth of Heaven and Earth rides the changes of the six breaths, and then roams amongst the boundless.
-- Zhuangzi (4th c. BCE Taoist master)
This immortal fourfold breath, is hidden in the original cavity of the spirit, behind the spot between the eyes.
-- Chao Pi Chen (20th c. Taoist master)

The Big Dipper God Tonrosho

Trigrams Li (Fire) representing the sun and Kan (Water) representing the moon, symbolize the medicine

Bodhisattva Guan Yin, holding the sun and the moon (Click to enlarge)

The Big Dipper head (on the right)
and handle (on the left)

The sheperd boy with the Big Dipper (ninth picture of the ten oxherding pictures

Hexagram #1 Heaven

(Click to enlarge)

A drawing of William Blake

A Magic Gourd Charm. Instead of a dragon, the image of a bat is used to symbolize the yang lines. At the place of the sixth dragon the Chinese character for 'Jade' (玉) is used.
(Click to enlarge)

As for the field of a square inch on the face, what can it be other than the heavenly heart? In the middle of the square inch dwells the splendour. In the purple hall of the City of Jade dwells the God of Utmost Emptiness and Life. -- The Secret of the Golden Flower

Sun Wukong, The Monkey King
with the full moon.

Hexagram #24 return and hexagram
#1 Heaven

The twelve sovereign hexagrams
(Click to enlarge)

Venus of Willendorf, estimated to have been carved .24,000–22,000 BCE. She is a symbol of the Earth Mother or Mother Goddess that can be found in all esoteric traditions. In Taoism she is called the Yellow Woman
or the Mysterious Female.

The twelve sovereign hexagrams arranged as inhalation and exhalation of six breaths, representing the balance of yin and tang during the firing process..
(Click to enlarge)

Six yin hexagrans of Greater Circuit of the Sky

The laughing Buddha, pregnant with the spiritual embryo

Six large and 4 small Jizo Bodhisattvas (Meaka-Fudoson, Nankokuji Temple, Tokyo)
(Click to enlarge)

A Tibetan master with a square third eye