During the Renaissance, medical practitioners embraced both magic and astrology in their efforts to heal the sick and wounded. They believed that the planets affected human health in profound but mysterious ways, and physicians routinely cast the horoscopes of their patients as part of their healing regimens. Some went so far as to harness the power of the heavens with astrological magic, crafting talismans to draw down beneficial influences from particular planets. These practices were rooted in ancient beliefs that the human body was the microcosm or “little world” that mirrored the structure of the wider universe, or macrocosm. These same ideas also informed the teachings of the medical reformer Paracelsus (1493-541), who advocated for the inclusion of astrology, alchemy, and magic in the practice of medicine. Rejecting the standard medical education, he advised instead that the physician should wander the world, seeking the hidden secrets implanted in plants and minerals by God. Nature itself was the divine apothecary, offering everything required to heal the sick, and for Paracelsus the discovery of medical properties in natural things was an act of piety and veneration.