This knowledge is highly theoretical and operational, and is called "Yi-ology". As far as its theory is concerned, it takes "qi" and "gas field" as the highest category, and basically does not talk about "ghosts" and "gods", thinking that all "ghosts" and "gods" are just the accumulation and dispersion of qi. It is believed that the so-called evil and blessing in the world are caused by the change of yin and yang and the relationship between the five elements. The relationship between this change of yin and yang and the generation of grams by the five elements exists in the natural environment in the form of qi. Kong Xuan's geomantic omen is not to study the laws of the changes of Yin and Yang and the relationship between birth and grams in the natural environment, so that people can understand these laws and use them to avoid misfortune.
There are many schools of Feng Shui, among which Kong Xuan Feng Shui is considered to be the most accurate. Metaphysics is the knowledge of choosing the best living environment in a certain period of time. Its theoretical basis is the gossip of Hutuluo's book. To make good use of metaphysics, we must grasp three important links: mountain, dragon and qi, which are closely related, interlocking and indispensable.
One of the most important principles of Kong Xuan's Feng Shui's destruction of Yang Zhai is "giving consideration to form and spirit", which is a main line of scientific inference of good and bad luck, and also runs through the whole operation of art. "Metaphysics" refers to the creation of mountains with star coil gas, and "giving consideration to form and spirit" means that qi and mountain creation should be coordinated and indispensable.