When the digestive process in the body is complete, certain signs arise to mark the onset of fever: hunger returns, dryness and lightness are felt in the limbs, and a gentle tenderness of fever is present. After eight days, the activity of the bodily humors becomes apparent, revealing the fever’s nature. Fever can emerge in many ways—sometimes from its own symptoms, sometimes by contact or contagion. When fever arises from such contact, a host of discomforts appear: headache, fainting, vomiting, burning sensations throughout the body, dryness of the throat and mouth, loss of taste, pain in the joints, sleeplessness, confusion, chills that make the skin bristle, frequent yawning, and excessive talking. These are the marks of fever driven by the disturbance of wind and bile. If the fever is caused by phlegm and wind, it brings a different set of troubles: the body loses its warmth, appetite fades, pain settles in the joints and head, spitting increases, breathing becomes labored, cough arises, the complexion grows pale, coldness and stiffness spread, darkness clouds the vision, dizziness and drowsiness set in. When phlegm and bile together give rise to fever, the body alternates between coldness and stiffness, and then sweating and burning. The person feels unstable, thirsty, and plagued by cough. The humors—phlegm and bile—move restlessly, causing confusion, drowsiness, a coating and bitterness in the mouth. The one who knows all the signs of fever can recognize its repeated burning. Such a person is seized by intense sleep, yet finds themselves wakeful during the day and sleepless at night. Sometimes sleep is constant, sometimes absent; sweating may pour forth, or not at all. The natural joys—singing, dancing, laughter—cease, and all such activities come to a halt. The eyes weep, becoming impure, red, sunken, and their lashes tremble. Pain flares at the sides of the eyeballs, in the head, joints, and bones, and dizziness persists. The ears may ring or ache, feel cold or remain unchanged. The tongue is burnt, rough, heavy, and the joints of the limbs grow weak and tremble. There may be spitting of blood and bile, rolling of the head, intense thirst, and the appearance of dark or red patches and circles on the body. Pain settles in the heart, the urge to pass waste becomes frequent, discharges may be scanty or excessive, the mouth feels oily, strength is lost, the voice turns hoarse, and speech becomes delirious. The humors ripen slowly, drowsiness persists, and a croaking sound echoes in the throat. When all three humors are disturbed together, the fever is said to destroy the very vitality of life. When wind is blocked in the throat and bile is greatly oppressed within, especially after indulgence in pleasure, the body seeks relief through external signs, and the eyes turn yellow—a mark of fever arising from the combined disturbance of the humors. If the humors are greatly increased and the digestive fire is lost, and all these signs are present, such fever—born of all three humors together—is incurable. Otherwise, though difficult, it may yet be cured. Sometimes, fever arises from the combination of humors, but bile remains separate; then burning is felt in the skin or abdomen, either before or after the main symptoms. Similarly, when wind and phlegm are involved, coldness predominates. Burning and similar symptoms are hard to overcome when both are present. At the beginning of coldness, bile lingers; with phlegm, oozing and dryness appear. When bile is pacified, fainting, intoxication, and thirst arise; but at the onset of burning, and in the other cases, drowsiness, lethargy, and vomiting follow in order. Fever, in its origin, is fourfold: it may arise from external injury, from contact, from curses, or from sorcery. Fever from injury is marked by burning and similar symptoms. Exertion often causes the wind to disturb the blood, leading to pain, sorrow, discoloration, and fever with pain. Fever can also arise from possession by spirits, from medicines, poison, anger, fear, grief, or desire. Sudden possession or mere contact, even the smell of certain medicines, can bring on fainting, headache, vomiting, and wasting. The scent of herbs may provoke these symptoms as well. Poison brings fainting, diarrhea, darkening of vision, burning, and dizziness. Anger causes trembling and headache. Fear and grief lead to delirium. Desire brings dizziness, loss of appetite, burning, shame, and disturbances of sleep, intellect, and memory. In cases of possession and similar causes, the symptoms of all three humors appear, and at first, those of wind and the others. Among fevers arising from anger or the excessive bile of rage, and those caused by curses or black magic, the two severe fevers of deranged humors are the most unbearable. When afflicted by spells and incantations of sorcery, the body is tormented; eruptions and confusion follow the initial bodily distress. For the one always seized by burning and fainting, the fever increases day by day. Thus, fever is seen in eight forms, but in summary, it is of two kinds: bodily or mental. It may be gentle or intense, internal or external in origin, natural or unnatural, curable or incurable, simple or complicated. In bodily fever, heat first arises in the body; in mental fever, it arises in the mind. When wind predominates, coldness is felt; when phlegm is present, coldness deepens. Burning occurs when bile is involved. When the humors are mixed, the disorder takes refuge internally. In fever, greater disorders arise, with agitation and retention of wastes. When the cause is external, the heat is also established outwardly. In the rainy, autumn, and spring seasons, fever arises from wind and other humors in their due order. The unnatural type of fever is different and difficult to cure, while the natural one most often arises from wind. During the rains, disturbed wind causes fever associated with bile and phlegm. In autumn, bile is produced, and phlegm follows. Due to the nature and release of these humors, there is no danger from eating various foods at that time. In spring, phlegm predominates, and then wind and bile may follow. When the disorder is mild, fever is curable and without complications. In all cases, when the disorder is recognized in advance, it is said to be incurable. The severity of fever’s complications includes weak digestion and excessive urination. There is no appetite, no proper digestion, no hunger, and the fever’s appearance is distinctive. Its intensity increases, bringing thirst, delirium, labored breathing, and dizziness. The urge to pass waste and its disturbance are signs that the fever is maturing. If there is no reversal, fasting for seven nights may bring resolution. Fever is said to be of five kinds, depending on the involvement of waste, the time of onset, the strength or weakness of the patient; but most often, fever is described as arising from the derangement of all three humors. There are continuous fevers, constant fevers, fevers that return every other day, every third day, or every fourth day. These are carried by the humors, urine, and feces, and are widespread due to the involvement of bodily wastes. They heat the entire body, increasing steadily from the beginning, strong and heavy, residing in the vital fluids without distinction. Such constant fever, without any respite, is extremely hard to endure. Fever or heat, or the disturbed humors, can quickly destroy the body. In all forms, whether the vital fluids and other substances are pure or impure, wind, bile, and phlegm cause fever in seven, six, or twelve days, each according to its own nature and course.