Paracelsus

Philippus Aureolus Theophrastus Bombastus von Hohenheim, who published under the name Paracelsus ("greater than Celsus," a reference to the first-century Roman encyclopedist Aulus Cornelius Celsus) was a Renaissance physician, botanist, alchemist, astrologer, and occultist. He pioneered the use of chemicals and minerals in medicine, and was among the first to credibly suggest that illness was the result of the body being attacked by outside agents, rather than an imbalance of the four Hippocratic humours. However, he is today remembered more for his contributions to alchemy and his magical theories, which stood in contrast to those of Cornelius Agrippa and Nicolas Flamel.