Objectives
This dissertation aims to study the treatment methods of Shanghan and Wenbing as a means to investigate the Han-Wen Unification Theory. The difference between treatment methods of Shanghan and Wenbing is more noticeable in exterior patterns than interior patterns which is Exterior-Cold pattern in which Pungent-Warm property medicinals are applied, and Exterior-Heat pattern in which Pungent-Cool property medicinals are applied, of Shanghan and Wenbing, respectively. The goal was to find a connection between Shanghan and Wenbing at this point that might enable the possible unification of Han(寒) and Wen(溫).

Methods
Firstly, the origins of exterior relief method through pungent-warm properties was examined to investigate the reason to the lack of exterior relief through pungent-cool medicinals at the time of the publication of 『Shanghanlun』. Next, the concept of exterior relief through pungent-cool before the establishment and introduction of Wenbing was examined. Lastly, while integrating the two approaches, the difference between the two approaches were examined within one integrated system, in regards to the possibility of unifying Han(寒) and Wen(溫).

Results and conclusion
In historical or medical texts before 『Huangdineijing』, exterior relief was achieved by means of various ways to heat the insterstices or through warm and hot medicinals. Afterwards in 『Huangdineijing』, promoting sweating was indicated for early stages of externally contracted disease. In 『Shanghanlun』, formulas that treated likewise conditions were mostly pungent and warm, whose approach was repeated in texts regarding the Five Circuits and Six Qi from the Tang period. However, in formula texts of the same period, cool property medicinals were used, unlike the pungent-warm medicinals of 『Shanghanlun』. This shows that the principle of 『Shanghanlun』 wasn''t exclusive, and that there is potential for modification of the principle.
Zhang Zhongjing''s method to apply pungent-warm medicinals to relieve the exterior in exterior symptoms was influenced by 『Huangdineijing』, 『Nanjing』, 『Tangyejing』, etc. Explanations to Zhang''s approach being heavily influenced by the cold weather in the latter period of Later Han is partly understandable, but not comprehensive. It is more reasonable to assume that his experience in treating diseases that fall into the Taiyang category in addition to his theoretical background on the Six Channel system contributed to the focus on the Taiyang pattern within the contents of 『Shanghanlun』.
After the publication of 『Shanghanlun』, doctors of later generations also treated external diseases according to the principles laid out in 『Shanghanlun』, using pungent-warm medicinals. However, as cases in which this approach failed accumulated, they started to modify or create new formulas, leading to the development of Exterior Relief Method through Pungent-Cool. In current textbooks which contain contents post-Wenbing, pungent-warm method is indicated as the appropriate treatment method for Shanghan, while pungent-cool method is indicated for treatment of Wenbing. However, when we look at the developmental process of the pungent-cool method for exterior relief, we can see that it still existed before being used to treat Wenbing. In other words, rather than the two methods being two different treatments to two different types of disease patterns, it can be understood that the pungent-cool method was developed in the process of dealing with the pungent-warm method''s limitations to treat certain cases, the two methods being two approaches to the same Shanghan disease pattern.
The pungent-warm method stimulates sweating, which makes it a general treatment method for exterior pattern. However in the case of pungent-cool method, rather than promoting sweating, it scatters inner stagnated heat, making it applicable to cases where both exterior and interior symptoms are present. To summarize, pungent-cool method is designed to treat not only the exterior pattern but also the interior pattern, whereas the pungent-warm method is designed to treat the exterior.
If we look at Shanghan and Wenbing as fundamentally the same disease, the pathogenic qi becomes one; and if we look at the pathogenic conditions as the deficiency and excessiveness of Zheng Qi or the existence of interior heat, in the case of Shanghan where exterior heat and aversion to cold is experienced in the early stages, the pungent-warm method is applicable. If we categorize according to the deficiency and excessiveness of Zheng Qi, when it is excessive before the onset of disease, Mahuangtang pattern manifests; when it is deficient, Guizhi pattern manifests. If there is heat or any other potentially influential factors at the onset of disease, Wenbing manifests and as both exterior and interior symptoms are present, the pungent-cool method could be applied. Therefore in cases of Wenbing where interior heat manifests in the early stage, it could be understood that rather it being caused by an entirely different pathogen, that there is a higher chance that there had been latent heat or an environment for developing heat. These environments for potential heat is likely to include Zheng Qi deficiency.
In conclusion, Shanghan and Wenbing could be viewed as the same disease manifesting in different patterns according to individual differences in bodily condition. Rather that seeing the difference in early stage symptoms as being caused by altogether different types of pathogens, this study suggests that one type of pathogenic qi and the condition of Zheng Qi, and the existence of heat inside the body contributes to the split into Shanghan and Wenbing. With this in mind, if we could choose between the two methods of relieving the exterior accordingly, it could build the foundation for unifying Han(寒) and Wen(溫).