Why does anger has something to do with spleen in both Chinese and English?

Question

The English word spleen has two meanings in Cambridge Advanced Learner's Dictionary,

1. an organ near the stomach which produces and cleans the body's blood.
2. a feeling of anger and disagreement.

Interestingly, Chinese character 脾, apart from the meaning of an organ, can also mean a feeling of anger in the word 脾气. Is this a coincidence?

I checked 《漢語大詞典》 for 脾气, and found that when interpreted as anger, all the examples are from modern Chinese literatures:

曹禺 《雷雨》第二幕： “哦， 太太怪可憐的， 為什麼老爺回來， 頭一次見太太就發這麼大的脾氣？” 趙樹理 《張來興》：“以前聽說這位老師傅有脾氣， 只是聽說。”
沙汀 《航線》： “那個買辦， 早被頑固的訴苦弄出脾氣來了。”

but when interpreted as disposition, there is examples from earlier literatures, like 《红楼梦》 from Qing dynasty.

人的習性。 亦借指事物的特性。 ▶ 《紅樓夢》第八四回： “都像 寶丫頭 那樣心胸兒、脾氣兒， 真是百裏挑一的。”

No corresponding meaning for spleen in English. Does this count as evidence that the meaning anger of 脾气 may be borrowed English?

In American Heritage Dictionary, there is a meaning labeled as Obsolete that reads: This organ conceived as the seat of emotions or passions. And in 《漢語大詞典》, there is a meaning of 脾气 with examples from literatures dating back to before Christ:

脾臟之氣. 《素問‧生氣通天論》： “是故味過於酸， 肝氣以津， 脾氣乃絕。”

This seems to has something to do with traditional Chinese medicine. Why does spleen is deemed to have something to do with emotion in both English and Chinese?

Answer 1

The term 發脾氣 fapiqi which literally means ‘emit the air of the spleen’ is often translated as ‘lose temper’. Its deeper cultural meaning will be explained in the section on metaphorical expressions. At this point, we would just note its reference to an internal feeling which is externalized, an emotional and physiological action which moves to the external world and manifests itself in various ways such as shouting at people or throwing objects.
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The metaphorical expression of 發脾氣 fa pi qi, ‘emit breath of the spleen’ requires further explication. The use of the spleen qi as the source domain is physically grounded in the theories of Chinese medicine. There are seven basic emotions, namely anger, joy, pensiveness, worry, grief, fear, and fright. Each is associated with one of the five phases: wood, fire, soil, metal and water, a specific organ and corresponding visceral vitality (Kendall, 2002). One emotion may give rise to or exert an influence on another emotion through the circular, acting and counteracting forces of the five phases. The emotion of anger resides in the liver. When a person is angry, the qi of the liver rises. As the liver is associated with wood, it exerts its influence over the spleen which belongs to soil. Abdominal distension and diarrhea may result as symptomatic manifestations of this adverse effect on the qi of the spleen. Therefore the metaphorical expression of 發脾氣 fa pi qi, ‘emit the qi of the spleen’ has a similar conceptual basis as sheng qi but is more specific about the visceral vitality that is affected.

• The language of anger in Chinese and English narratives

This does indeed seem analogous to the English expression to vent one's spleen. The connection is likely coincidental though, since the spleen is associated with various different emotions in different languages, and originally melancoholy in English, not anger.