Plants, magic, medicine

Since antiquity plants were thought to have a spirit, called psyke by the Greeks, that made them sensitive to pain and joy. Some plants were considered magical and able to perform feats, such as hypericum (St John's wort) and mandrake, which was thought to be able to kill a man who attempted to uproot it. Such beliefs were the direct consequence of the distorted interpretation of the effects these plants had on man. Though today we are not surprised to know that poisonous, hallucinogenic, sedative and anaesthetic plants exist, in antiquity these properties could not be interpreted with today's scientific precision. Popular legends arose from exaggeration of these effects due to the desire of "herbalists" of the period to demonstrate the efficaciousness of their medicines.

That did not prevent, however, the understanding that plants have pharmacological actions. Thus hypericum, a species used to treat madness and hysteria, whose manifestations were attributed to diabolical possession, was an excellent sedative and antidepressant. Equally, the potion used by Circe to transform Odysseus's companions into swine was probably composed of herbs able to alter consciousness and thus render men "similar to beasts". Similarly, the rituals linked to the gathering of medicinal herbs were suggestive of, though in a somewhat fanciful fashion, the balsamic time and the methods of collection to be used. For example, the rising of the Pleiades constellation (in May) or working the ground naked gave sufficiently precise instructions on the best period to do it.