Great article, though I have one quibble with it.
In Chinese cosmology, the hun and po are, although a pair in one sense, also part of a larger group of five souls that include the zhi (will), shen (spirit), and yi (intent). Being a group of five, they are correlated to the five elements and in Chinese medicine with the five important yin organs -
earth - Spleen/Pancreas - Yi (intent)
metal - Lungs - Po
water - Kidneys - Zhi (will)
wood - Liver - Hun
fire - Heart - Shen (spirit)
The point being that if you are going to go back into Chinese cosmology, it is somewhat problemmatic to translate hun as "intent", as there is another very similar term used for that idea. Yi is also the term used in all Chinese arts that talk about intent, such as I Liq Chuan, Xing Yi, Xin Yi, Yi Quan, etc. Hun and po are, to my knowledge, not used as technical terms in Chinese martial arts nearly as much as yi and shen.
To add some further info, one way that the hun and po are described is that the hun is the soul that leaves the body at night when you dream, and the po is the soul that is responsible for our ability to, in a sense, "be in our body" and really experience the physical world, especially through our sense of touch. This aspect of the po is connected to its association with the lungs, as the lungs are, in Chinese medicine, connected to the health of the skin, since the lungs are the one internal organ that is in contact with the outside world directly and can be considered to be an extension of the skin. The po is also the soul that can remain and become a ghost after death and cause trouble; this may be related to the presence of the character for "white" in the character for po, as the white may be a reference to the color of dried bones, which are the part of the body that remain the longest after death.