The interplay between the Yin and the Yang aspects of everything that is governs all universal phenomena, whilst Qi gives it form by way of condensing to different degrees. 

The organism’s Vital Energy, or Qi, in quality of energy and information that cannot be perceived through the five senses, is considered Yang, whilst the matter that forms its structure is considered Yin. Consequentially, Qi itself is considered Yang, being ethereal, whilst its material equivalent, the blood, is considered Yin. Psychological and cognitive activity is considered Yang relatively to the metabolic activity and can in itself be further distinguished in ‘more Yin’ and ‘more Yang’ aspects, thus the neuro-motor activity is Yin relatively to the the neuro-sensorial activity. ‘Zhuo’, dense substances, are considered Yin relatively to ‘Qing’, fluid substances.