The martial tradition is most closely associated with the Southern tradition of Daoist practice with its initial use of physical culture to enhance mental / spiritual development. However all Daoist traditions have at their core the same underlying concepts and theories.

The starting point is the term “Dao” 道. At its most fundamental, refers to the creation of the universe and all things that came into existence following that moment. Because the Dao simultaneously encompasses everything in existence yet in itself is not physically manifest, Laozi 老子, the alleged author of the Daode Jing 道德經, wrote in his opening lines:

The Way that can be described is not the absolute Way;
the name that can be given is not the absolute name.
Nameless it is the source of heaven and earth;
named it is the mother of all things.

The complete text can be found here http://www.san.beck.org/Laotzu.html

The Daoist theory of creation is illustrated below.

The diagram represents from the top;

The empty circle = Wu Ji Pre Celestial existence. This is before differentiation takes place.

The circle with black and white sections = Taiji Post Celestial existence. This is the first stage of differentiation. The black represents Yin 陰 and the white represents Yang 昜 all things manifest can be classified into Yin or Yang. Yin is analogous with; earth, dark, female, soft etc. Yang is analogous with; heaven, light, male, hard etc. Yin and Yang within Taiji are not separate but merely different manifestations of one unified energy.

The next level illustrates further differentiation into five phases or elements = Wuxing 五行. It should be remembered that just as Yin and Yang are still part of a single whole the same is true of the five phases.

The next two circles illustrate the concept that all things can be considered to be either Pre or Post Celestial in nature. The first circle illustrates the perfect male and female principle. The second refers to "The Ten Thousand Things produced". All things that are physically manifest are considered to be Post celestial in nature. Things that are more manifest in an energetic way, the "perfect principals", are considered to be Pre Celestial. Therefore in terms of practice physical activities such as Dao Yin, TJQ form or XYQ form practice would be considered to be Post Celestial practice. Meditation should strive to be a Pre Celestial practice.

As mentioned above, the martial tradition is closely connected with the Southern Daoist tradition. Both Northern and Southern traditions use what is referred to as dual cultivation. This indicates that both physical (life) and mental (essence) should be cultivated. The main difference is one of emphasis. The Northern School was heavily influenced by Chan (Zen) Buddhism. As a result the Northern school places greater initial importance on the mental (essence) aspect of training, whereas the Southern school initially works more on the physical side (life) of cultivation. Ultimately all practice should culminate in mental cultivation as this enables the practitioner to return to a Pre Celestial state.

It is thought that the differences emerged because of the difference in ages and backgrounds of the founders of the different schools and how they established their respective traditions.

The Northern School is almost entirely monastic in nature and as with most monasteries, its members join at relatively early ages and are then, to a large degree, separate from society. The Southern School on the other hand is carried on in a more informal setting relying upon a master to disciple transmission. The members of this tradition usually start at a later stage in life and continue to function within society. Because members of the Northern School are younger, more energetic and usually without family responsibilities they are able to practice a more purely Pre Celestial (meditational) method. Members of the Southern School on the other hand benefit from a variety of physical practices, Post Celestial, to re-energise the body so that they can then move to the Pre Celestial method of cultivation.

These methods of physical cultivation can include any or all of the following:

Massage. This can be carried out on oneself or a partner. The aim is primarily to relax the body and mind. Some form of self message is usually carried out at the beginning and end of sitting meditation practice. It can also be used to carry out passive stretches to enhance flexibility.

Dao Yin. More details can be found here, but briefly Dao Yin is a gentle method of Yoga. It is designed to loosen and relax the body making it more able to carry out extended periods of sitting meditation.

Martial Arts. Although both Xingyiquan and Taijiquan utilise Daoist theory in their practice they cannot actually trace their origins directly back to Daoism. But given that nothing exists in a vacuum, it is likely that they were influenced by other methods that did have Daoist origins.

Paired Cultivation. (Sexual Yoga) This is an area of practice that clearly differentiates between Northern and Southern traditions. The Northern School because of its monastic tradition does not utilise sexual yoga. The Southern School on the other hand because of the factors outlined above, acknowledges the value of paired cultivation to help practitioners revitalise their bodies in order to benefit from Pre Celestial practice at a later stage.

The origins of the River Diagram are lost in pre-history. Fu Xi, Daoism’s most ancient ancestor, is believed to have written this design having observed the structure and actions of the heaven, earth and living creatures. The dots are in two sets, pre and post celestial. The River Diagram is associated with the five phases.

The Lo writing is considered to be from a slightly less distant point in history. The design of the Lo writing is quite straight forward. As you can see, it consists of nine sets of dots around the outside, one set in each of the four cardinal directions, a set in each of the intermediate directions and one set (5) in the centre.

You should note the layout of the River diagram. The number of dots on the outer are the product of adding five to the inner number. The inner numbers are considered to be Yang / Pre celestial manifestations and the larger outer numbers are the Yin / Post Celestial manifestations of the five phases. The five phases (Wuxing) in the River Diagram placed in a creative order as follows: Water (1,6 ) generates Wood (3,8) generates Fire (2,7) generates Earth (5,10) generates Metal (4,9).

In Daoist cultivation the five phases are also allocated various mental and physical facets, again each one being allocated a higher, usually referred to as being “original”, or lower position. The psychological facets are: Water = Original Vitality / Turbid Vitality, Fire = Original Spirit / Ordinary Awareness, Wood = Original Essence / Human Temperament, Metal = Original Sense / Feelings - Emotions, Earth = Original Energy - True Will / Wandering Thought.

You may have spotted that the Lo Writing is a development of the River Diagram. It illustrates a destructive cycle. Yin Water (Turbid Vitality) overcomes Yang Fire (Original Spirit), Yin Fire (Ordinary Awareness) overcomes Yang Metal (Original Sense), Yin Metal (Emotions) overcome Yang Wood (Original Essence), Yin Wood (Human Temperament) overcomes Yang Earth (Original Energy) and Yin Earth (Wandering Thought) overcomes Yang Water (Original Vitality).

For those who are not Sodoku fans and failed to spot the numerical significance of the above layouts.

The above cycle is expounding Daoist theory how humans lose their innate nature through exposure to temporal form. The ultimate aim of Daoist practice is to reverse this loss of innate nature and because the loss is owed to the effects of temporal forms, practice should, at least partly, be of the Post Celestial (temporal) type.

It is the failure to understand this aspect that causes much misunderstanding, particularly in the martial arts community. People with a passing familiarity with the concepts outlined here are aware of the phrase “Wu Wei” (non doing), this is frequently thought to mean doing nothing and by extension the idea that expending effort is to be frowned upon.

The true meaning is nearer to being; what you do should be in accordance with the circumstances of the time. Combine this misunderstanding with the even more basic inability to recognise that martial practice falls within the category of Post Celestial practice which by definition is physical in nature, leads to many practitioners actively avoiding any type of exertion during practice, thinking that they are somehow getting closer to the Daoist ideal!

A further evolution of Daoist cosmology can be seen in the diagram below. This shows how single lines representing Yin (broken) and Yang (solid) lines develop. Firstly by pairing up. The upper representing Heaven / Yang and the lower Earth / Yin. The next row develops by adding a third line which represents humanity, thus representing the Triad. The images are referred to as Trigrams.

The Trigrams can then be paired up, again representing Yin and Yang aspects. This pairing is referred to as a Hexagram. The Trigrams can be mixed into a total of 64 Hexagrams. The sixty four hexagrams are at the core of the classic text the YiJing (I Ching).

The Trigrams can be presented in various ways. The two main ways are, again, described as being either Pre Celestial (left) or Post Celestial (right). Both versions are shown below.

You can see how the above theory is applied to the practice of Tajiquan here.