The Philosophy of Natural Magic, by Henry Cornelius Agrippa, L. W. de Laurence ed. , at sacred-texts.com
The phantasy, or imaginative power, hath a ruling power over the passions of the soul when they follow the sensual apprehension. For this doth, of its own power, according to the diversity of the passions, first of all, change the proper body with a sensible transmutation, by changing the accidents in the body, and by moving the spirit upward or downward, inward or outward, and by producing divers qualities in the members. So in joy, the spirits are driven outward; in fear, drawn back; in bashfulness, are moved to the brain. So in joy, the heart is dilated outward, by little and little; in sadness, is constrained, by little and little, inward. After the same manner in anger or fear, but suddenly. Again anger, or desire of revenge, produceth heat, redness, a bitter taste and a looseness. Fear induceth cold, trembling of the heart, speechlessness and paleness. Sadness causeth sweat and a bluish whiteness. Pity, which is a kind of sadness, doth often ill affect the body of him that takes pity, though it seems to be the body of another man so affected. Also, it is manifest that amongst some lovers there is such a strong tie of love that what the one suffers the other suffers. Anxiety induceth dryness and blackness. And how great heats love stirs up in the liver and pulse, physicians know, divining by that kind of judgment the name of the one that is so beloved in an heroic passion. So Naustratus knew that Antiochus was taken with the love of Stratonica. It is also manifest that such like passions, when they are most vehement, may cause death. And this is manifest to all men, that with too much joy, sadness,
love, hatred, men many times die, and are sometimes freed from a disease. And so we read that Sophocles, and Dionysius, the Sicilian tyrant, did both suddenly die at the news of a tragical victory. So a certain woman, also, seeing her son returning from the Canensian battle, died suddenly. Now, what sadness can do is known to all. We know that dogs oftentimes die with sadness because of the death of their masters. Sometimes, also, by reason of these like passions, long diseases follow, and are sometimes cured. So, also, some men looking from a high place, by reason of great fear, tremble, are dim-sighted and weakened, and sometimes lose their senses. So fears and falling-sickness sometimes follow sobbing. Sometimes wonderful effects are produced, as in the son of Crœsus, whom his mother brought forth dumb, yet a vehement fear and ardent affection made him speak, which naturally he could never do. So with a sudden fall, oftentimes life, sense, or motion, on a sudden, leave the members, and presently again, are sometimes returned. And how much vehement anger, joined with great audacity, can do, Alexander the Great shows, who, being circumvented with a battle in India, was seen to send forth from himself lightning and fire; the father of Theodoricus is said to have sent forth out of his body sparks of fire, so that sparkling flames did leap out with a noise. And such like things sometimes appear in beasts, as in the horse of Tiberius, which was said to send forth a flame out of his mouth.