Plato was aware that divination is something inferior that pertains to the non-rational soul. The main point is that they [clairvoyants] name their illnesses, especially chronic nervous disorders that are not yet fully developed. Also, rheumatism, toothaches, yield to magnetism. Remarkably, it seems to have an effect on the maladies of menstruation. The somnambulists especially know how to specify these disorders and it is easy to admit that they discover deficiencies. They describe these conditions, but in an entirely ordinary manner, not in the manner of one who understands anatomy. Then they indicate the remedy for their disease.
Plato