An archaic surgical procedure, the skull trepanning, was introduced in ancient Greece to treat brain derangement, and endured until the 18th century with the same use. Hippocrates recognized epilepsy as a common entity and categorized it as a brain disorder, removing any divine origin. He proposed that the excess of black bile and mucus is due to the infiltration of air inside the blood circulation (veins). For him it was a hereditary disease that could be cured. Thus, he suggested a non-invasive treatment based on herbal potions, and a surgical treatment by using the most advanced operation of the era, the open brain drilling, known as trepanning, or trephination, setting the beginning of neurosurgery.