New Light on Early Paracelsianism

Jole Shackleford. A Philosophical Path for Paracelsian Medicine: The Ideas, Intellectual Context, and Influence of Petrus Severinus, 1540–1602. Copenhagen: Museum Tusculanum, 2004. 535 pp. $91.

Reviewed by Dane T. Daniel

The Danish royal physician and Paracelsian Petrus Severinus complained, “If we can make more potent drugs], extracted from metals and minerals, . . . I ask, what age except this one will oppose our efforts?” (p. 115). Severinus was so adamant because early modern attempts to prepare and prescribe drugs forged in the alchemical laboratory often faced vehement opposition from university-trained physicians weaned on the humoral theory and herbal materia medica of Galen. After all, Paracelsians—followers of Theoprastus Bomast on Hohenheim (1493/4–1541), the controversial alchemist and medical practitioner who styled himself as Paracelsus—dismissed the belief that disease was the result of humoral imbalances in favor of the notion that the human body was a microcosm of the natural world and that diseases were essences, or actual beings.

Severinus was correct that chemical medicine would find popularity in another era, but—as Jole Shackelford notes in the introduction to his Philosophical Path for Paracelsian Medicine—the concepts of Paracelsus and his followers have remained peripheral to the grand narratives of early modern intellectual history. Shackelford sheds much-needed light on this significant strand of 16th- and 17th-century science and medicine. Via text-oriented study, particularly of Severinus’s Idea medicinae philosophicae [Ideal of philosophical medicine] (1571), Shackelford provides a meticulous biographical account of Severinus and explains with refreshing clarity the sources and speculative theory behind his brand of chemical medicine.

After establishing Severinus’s importance as a populizer of Paracelsus, Shackelford traces how Severinus joined his friend Pratensis (a recognized Paracelsian) and Tycho Brahe in bringing Denmark up to continental cultural and intellectual standards. The appointment of Severinus as physician to the king prevented him from completing most of his research projects, but he had already left for posterity his Idea medicinae. Amalgamating Neoplatonism, the Hippocratic tradition, and Paracelsus’s theories, the Idea medicinae presented Severinus’s theory of semina—immaterial loci that accounted for all change in the subvisible world and could be observed through chemical analysis. Unlike Robert Boyle’s inertial, material corpuscles and their active principles, Severinus’s semina were “intrinsically formal and immaterial, and were logically and ontologically prior to matter” (p. 17).

Shackelford shows that Severinus’s ideas can be found in hundreds of contexts, including poetry, geology, and medicine. His discussion of the neglected topic of Paracelsian therapeutics, especially his evaluation of William Davidson’s application of Severinus’s semina theory to the treatment of fevers in mid-17th-century Paris, is welcome. A Philosophical Path for Paracelsian Medicine is graced with numerous useful pictures and illustrations, including a personal photo by Shackelford of a drug jar that had contained Species Tychonis Brahei, sold in Copenhagen at the beginning of the 20th century. Overall, this book is an entertaining and important contribution to the history of early modern chemistry, medicine, and ideas.