These psychological factors, if in excess, can cause disease and ill-health.
To the Westerners, joy is a cheerful, positive concept that we find difficult to see as damaging. The positive side of Joy seen in these terms is beneficial.
However, Traditional Chinese society was excessively hierarchical and deeply conservative. Therefore, Joy could be seen in terms of overexuberance and inappropriate behavior, and it is damaging. There is a saying in Chinese : "Sorrow grows out of excessive joy."
We can perhaps imagine "Joy" as a rowdy group of excited teenagers yelling noisily in the street and upsetting elderly passers-by, rather than the happy sense of contentment and light-heartedness associated with the word in the West.
This "inappropriateness" is the negative aspect of Joy and too much of it will damage the Heart and also the Lungs which are located close by in the Upper fiao.
Too much Joy damaging Heart Qi. It can lead to an inability to concentrate, while the sort of hysterical laughter associated with some forms of mental disorder is also associated by the Chinese with damaged Heart Qi.
This association can be easily understood in the West; its symptoms are "panic attacks," with their palpitations, mental restlessness, and cold sweats. In Chinese medicine, fright is said to send the Heart Qi "wandering about, adhering to nothing." Therefore, the heartbeat will speed up, and thus add more burden to the heart.
The result is stagnation of Spleen Qi, which in Chinese medicine theory manifests as depression, anxiety, poor appetite, weakened limbs, abdominal bloating, and, in women, menstrual irregularities.
Pensiveness is said to originate in the Heart, so an excess can damage Heart Qi. A common syndrome associated with excess worry is described as "depressed Heat in the Heart and Spleen", which can involve insomnia, palpitations, and constipation.
Sadness affecting the lungs is very common and may be observed as bronchitis and asthmatic problems, for example. They frequently seem to follow bereavement, while chesty coughs are common in those who are unhappy.
Symptoms include those associated with "shock" in the West - pallor, breathing problems, and a sense of suffocation in the chest, as well as loss of appetite, constipation, and urinary problems.
In the West, the liver is traditionally associated with strong emotions notably love and bravery. Westerners have absorbed some of the Chinese imagery for this in the term gung-ho, with its association of excess activity and military aggression. It is said to derive from the Chinese word for "Liver Fire".