The cause of weakness acts either on the body of the organ, or on the pneuma, the supporting force that controls the organ, or on this force itself. The reason associated with the organ itself is sometimes the poor quality of the nature entrenched in the organ, especially a cold one. However, the hot nature sometimes has, by weakening the organ, the same effect as the cold one, for it causes numbness, spoiling the nature of the pneuma. This happens to those who stay in the bathhouse for a long time, or rather, to those who faint from it; and a dry nature, producing compaction, prevents forces from passing to the organs, while a wet nature causes weakness, making the organ sluggish, and clogs it.
Sometimes the cause of weakness is some disease from a combination of diseases. The most specific thing in this case, although a person does not outwardly seem sick, suffering or unhealthy, is the rarefaction of tissue in the fibers of a given organ, because all natural and voluntary actions are performed with the help of fibers and because they are tightly connected. Digestion also requires the food to be firmly grasped properly, and this is accomplished by fibers.
The cause associated with pneuma is either the poor quality of nature, or the dispersion of pneuma, which occurred either due to emptying affecting the pneuma itself, or as a consequence of the eruption of something else.
The cause related to strength is the frequency of actions and repetition of actions that weaken the strength. However, this is sometimes accompanied by dissipation of pneuma, since one cause often accompanies another.
If we enumerate the causes of weakness in a different way and cite among them individual causes that are the causes of immediate causes, then we will find among them the causes of poor quality of nature, which include spoiled air, water and food, as well as causes that initially repel the pneuma, such as, for example, stench, spoiled water and the spread of poisonous forces in the air or in the body.
The causes of weakness include phenomena associated with bowel movements, for example, bleeding and diarrhea, especially the eruption of liquid juices, the flow of water during dropsy, if it immediately rushes out in large quantities, as well as the prompt opening of many abscesses, if a lot of pus flows from them at once; the same thing happens if they open themselves.
These same causes include profuse sweating, excessive exercise, as well as pain, because they dissipate pneuma, even if the nature has already undergone a change. These pains include those that act more strongly, such as pain in the mouth of the stomach, pulling or burning, or pain in a part of an organ, as well as any pain near the heart.
The fevers are relieved by the dissolution and emptying of blood and pneuma. Changes in nature and excessive pore width also contribute to weakness from resorption of juices; This also includes frequent fasting. Sometimes weakness of the body is a consequence of the weakness of one organ or part of another organ: such is the weakness of the body due to damage to the mouth of the stomach, reaching the point that all the person’s strength is dissipated.
When a person's heart and brain respond strongly to minor injuries, such a person quickly begins to get irritated and tormented by the slightest trifle.
Often the cause of weakness is the experience of many diseases, and sometimes one organ is created weaker than the other paired organ or weaker than the same organ in another person, such as the lungs or the brain. A weak organ rather accepts matter that an organ created by a strong one drives away from itself.
If the brain were not given a particularly elevated position, it would suffer unbearably from all this and it would have no strength left under such suffering.