Johannes' de Rupescissa `Liber de consideratione quintae essentiae omnium rerum' deutsch: Studien zur Alchemia medica des 15. bis 17. Jahrhunderts mit kritischer Edition des Textes

Various cases of treatment recorded by Yagel demonstrate his synthesis of medicine with astrology and Judaism. The contemporary view ofdemonology in relation to disease is shown to include rabbinic and Cabalistic ideas. The author shows how Yagel's study of nature reaffirmed his belief in the unity of God and discusses his attitude towards prodigies of nature, contemporary scientific discovery, and various forms of magic. The interchange between Christian and Jewish thinkers at the time and the universality ofall learning, a theme common to much of Yagel's writings, are cogently described. Yagel's familiarity with contemporary thinking and his use of rabbinic thought to harmonize unorthodox practice with religious doctrine illustrate the distinctive capacity of Jewish thought to adapt to current thinking while retaining continuity with its roots. In the final two chapters, Yagel's views on metempsychosis are discussed. His wide-ranging knowledge of Christian and Jewish theology along with current scientific and philosophical thought led him to the conclusion that as life is not futile it must represent some form of purgatory. His understanding of Cabala is described as a rational science adaptable to the language of academic discourse, but at the same time Yagel claimed that only the Cabalist can fully comprehend the mysteries of creation. The author brings us into the world of intellectual Judaism at a transitional period in European thought and demonstrates how Judaism could adapt to those ideas yet retain its identity and at the same time attempt to command respect within the larger intellectual community as a whole. This is an admirable introduction, both readable and erudite, to a very large and complex subject. The 'Book on considering the fifth essence of all things' was written around 1350 by the Franciscan monk Johannes de Rupescissa, Jean de Rocquetaillade, who was not a Catalan, as earlier supposed, but was born in the Auvergne. Because of his prophecies of the impending end of the world and coming ofthe Antichrist he spent much ofhis life on the run and injail. Perhaps it is there that he found the time for his other writings, namely on medical alchemy. This was a method of supplementing the use of Galenic medicine by preparing remedies by means of combining distillation and dissolution in strong inorganic acids and using alchemical methods for preparing metal and mineral quintessences as well as plant distillates. The quintessence was originally the essence of the four elements. These four …