From the changing of the seasons to the passing of time, every principle that underpins the basic premise upon which Chinese medicine is founded on the Yin Yang theory – the absolute belief that every energy source in the universe that we know (and perhaps beyond) is either yin or yang.

As with most beliefs, the theory of yin and yang isn’t a simple one and there isn’t one absolute truth. Every interaction between energies is always a fusion of both yin and yang – there is no ‘energy genus’ into which we can conveniently label one thing yin or another yang.

The fundamental basis of the theory is acceptance that two things can be opposites, but also entirely complementary, balanced between and dependent upon each other for existence, power and meaning. Put simply, there can be no Yin without Yang, no Yang without Yin.

But to understand the theory properly is to accept that there are some broad concepts which, whilst not being rules, can nevertheless be considered as being consistent.

Because they are intrinsically opposites (until they come together), it’s reasonable to generally define objects or concepts that are warm, bright and moving to be Yang, whilst cold, dark and still ideas and items may generally be considered to be Yin.

In terms of how the theory of Yin and Yang applies to acupuncture, it’s necessary to understand that every situation, circumstance, process and organism has opposite sides – Yin and Yang. This also holds true for the human body, which we can separate conceptually as exterior or interior and hot or cold.

The belief structure that sits behind ancient Traditional Chinese Medicine is that a person’s health deteriorates when these ‘opposites’ are out of balance – or, put another way, when the Yin is out of step with the Yang.

For example, where Yin – cold, dark and still – is the dominant force in the body, damage is caused to the Yang qi. As the dominant ‘opposite’ this excess Yin would lead to a cold disease. And the reverse is also true, with dominant Yang damaging the Yin qi, leading to a hot condition.

Acupuncture treatments are at the centre of the Yin and Yang theory because they attempt to re-establish a balance between the body’s Yin and Yang. Once this is achieved, natural healing is believed to be inevitable.