Paracelsus, born Theophrastus Bombastus von Hohenheim in Einsiedeln, Switzerland, was the son of a physician from whom he received his early training in medicine and alchemy. His assumed name stems from his claim to have surpassed the Roman physician Celsus. He traveled with his father to Villach in Austria where he worked as an apprentice in the mines and acquired much of his practical knowledge of mineralogy and metallurgy. He left the mines in 1507, attended various German universities, and may have obtained an MD from Ferrara. After practicing medicine in Sweden, Strasbourg, Basel, Nuremburg, and a host of other places, in 1540 Paracelsus settled in Salzburg where he died in the following year.

Paracelsus was the first to reject totally the authority of antiquity, suggesting its replacement by nature and experiment. To show his seriousness he burned the great medieval compilation of medical knowledge, the Canon of Avicenna, before his students. In Basel he was lucky enough to cure the infected limb of an influential publisher Frebenius, for which orthodox physicians had recommended amputation. This led to his appointment as professor of medicine and city physician at Basel.

His contempt for traditional learning and the reason the medical authorities found him so distasteful is best conveyed by his much quoted riposte to them: “Let me tell you this: every little hair on my neck knows more than you and all your scribes, and my shoe-buckles are more learned than your Galen and Avicenna, and my beard has more experience than all your high colleges.” The alternative proposed by Paracelsus contained a number of not particularly coherent strands. There was much in his work that belonged to, or at least overlapped with, the occult tradition but there was an eagerness to embrace new sources of knowledge. He would willingly learn his chemistry from the craftsmen in the mines and claimed to gain knowledge from gypsies, magicians, and elderly country folk.

His greatest influence on 16th-century science arose from his chemical philosophy in which he posed the ‘tria prima’: salt, sulfur, and mercury. These terms were meant to emphasize the principles of solidity, combustibility, and liquidity inherent in any substance. It was by following through the implications of such schemes that later chemists such as Robert Boyle were led to the corpuscular view of matter.

In medicine Paracelsus took the revolutionary step of introducing chemically prepared drugs rather than persisting exclusively with the herbal medicines or ‘simples’ of antiquity. While he was perhaps not the first to use such new remedies as mercury, sulfur, potassium, and antimony his dramatic use of them, often with supposedly verified cures, brought them sharply before the attention of the public. It is from this work that medicine begins to take on its modern aspect as being concerned with the discovery of specialized drugs providing complete and harmless cures.