One of the earliest attempts to explain the origin of mental diseases perhaps was that of Plato. "There are two kinds of madness, one arising from human diseases, the other from an inspired deviation from established custom." Hippocrates[56] had some very clearly defined views on this subject: "As long as the brain is at rest a man enjoys his reason; but the depravement of the brain arises from phlegm and bile, either of which you may recognise in this manner: Those who are mad from phlegm are quiet, and do not cry out or make a noise, but those from bile are vociferous, malignant, and will not be quiet, but are always doing something improper. If the madness be constant, these are the causes thereof; but if terrors and fears assail, they are connected with derangement of the brain, and derangement is owing to its being heated. And it is heated by bile when it is determined to the brain along the blood-vessels running from the trunk, and fear is present until it return again to the veins and trunk, when it ceases. He is grieved and troubled when the brain is unreasonably cooled and contracted beyond its wont. It suffers this from phlegm, and from the same affection the patient becomes oblivious." An interesting theory which he evolved was that the appearance of varicose veins or hemorrhoids tended to relieve the patient's mental suffering. Celsus subscribed to the black bile doctrine. Galen's teaching was that fatuity was due to moisture, while dryness produced sagacity. In cases where the whole body contained melancholy blood he recommended venesection. Thick and black wine was to be avoided, "as from it the melancholy humour is made."[57] This he described as a condition of the blood "thickened, and more like black bile, which exhaling to the brain, causes melancholy symptoms to affect the mind." The Roman custom of appealing to the household gods, sons of the Goddess of Madness, was quite significant. Horace, in speaking of Orestes, says: "Was he not driven into frenzy by those wicked Furies, before he pierced his mother's throat with the reeking point of his sword? Nay, from the time that Orestes passed for being unsound of mind he did nothing in any way to be condemned; he never dared wound with his sword either his friend Pylades or his sister Electra; he merely abused both, calling one a Fury, the other some other name suggested by his active or bright bile." In the story of Argive, Horace says that "his relations cured him with much labour and care, by expelling the disease and the bile by doses of pure hellebore."