The Secret Pharmacopeia of Pope John XXI

The Secret Pharmacopeia of Pope John XXI: Extracts from the Thesaurus Pauperum offers English translations from a remarkable volume, entitled Thesaurus Pauperum (‘The Pauper’s Treasury’). The author of this historically important and curious work was Pope John XXI (1215-1277). Portuguese by birth, and known as Pedro Julião or Petrus Hispanus (‘Peter the Spaniard’) before being chosen as pontiff, he had a well-deserved reputation as one of the most outstanding physicians, logicians, and scientists of his time. After John’s death, rumours quickly spread that he was a secret practitioner of necromancy and the black arts, and that his untimely death was, in fact, an act of God intended to prevent him from completing a certain heretical treatise which he was engaged in preparing.

Alas, the Thesaurus Pauperum was not that treatise; however, it is a fascinating collection of ‘home remedies’ and secret cures for a wide variety physical and emotional ailments, including baldness, insomnia, headache, pimples, gallstones, redness of the throat, nausea, coughs, toothache, sore eyes, earache, impotence, and many others (a few of which are virtually untranslatable into ‘polite English’). This Guide to the Underworld offers a modern translation of a small but representative selection of these remedies.

The Secret Pharmacopeia of Pope John XXI: Extracts from the Thesaurus Pauperum
Translated by Fr. Robert Nixon, OSB
ISBN 978-1-915933-01-0
A Guide to the Underworld
19 pages
Published March 2024