The Heart and Spine Under Leo

Leo takes the heart, the upper back and the spine. This is the one assignment in the melothesia that agrees with the separate scheme of planetary rulership, since Leo is ruled by the Sun and the Sun rules the heart in the planetary scheme as well; the double agreement made the heart-Sun-Leo correspondence unusually stable across the tradition. The classical basis is the analogy of the Sun as the centre and source of the cosmos to the heart as the centre and source of the body, an analogy that predates astrology and appears in Greek medical and philosophical writing. Medieval texts read the region for complaints of the heart and of the spine and for conditions of vital heat. The atlas records the correspondence for its history; it carries no medical weight.

The heart's philosophical status in Greek thought predates and reinforced its astrological one: Aristotle held the heart, not the brain, to be the seat of the soul and of intelligence, a cardiocentric physiology at odds with Plato's brain-centred view in the Timaeus, and later Stoic writers generally followed Aristotle's line. The melothesia scheme sits comfortably with the Aristotelian view and less comfortably with the Platonic one, which is one reason the head-brain-Aries pairing that opens the sequence and the heart-Leo pairing at its centre have never been treated by the tradition as being in tension with one another, even though a strict cardiocentric physiology would give the heart, not the head, pride of place.

Sources AstronomicaMarcus Manilius with Ancient MedicineVivian Nutton