The Si Period refers to the time between 9am to 11am and is also the period when the spleen channels are on duty. The spleen is the main key in aiding digestion because the breakfast taken in the Chen Period will begin undergoing the process of digestion in this period. Our stomach is like a cooking pot; when we eat, the food goes into our stomachs, just like how one would put food into the pot to cook. How does the food get digested then? Using the same analogy, one needs "fire" to "cook" the food in stomach, thus the "fire" here refers to the spleen in your body. Digestion relies on the spleen to slowly "cook" the food in the stomach.

What is the spleen channel then? The Chinese character of spleen "Pi" is spelled with two parts, and the character on the right "Bi" is just like a young maid in ancient times standing by the fire and tending to it by adding firewood and all. In the internal organs, the spleen is like that young maid busy tending the fire, but if she (it) falls sick, other internal organs will become very uncomfortable, and may get a so-called "Rich Man's disease" (due to eating too much junk food) such as diabetes, etc. If one's body appears to be losing weight and becoming skinny, or starts salivating uncontrollably, or feeling muscles tightly turgid and gaining weight, etc., are all considered lienopathia which is caused by the disorders of spleen channel in TCM philosophy.