The Liber Uricrisiarum

The Liber Uricrisiarum (written and revised c. 1375-82) is the earliest known work of academic medicine written in Middle English. The text survives, in various forms, in thirty-three separate manuscripts and two slightly different early print editions. This wide circulation attests to the text’s cultural importance in medieval and early modern England: even a now-canonical literary work like Geoffrey Chaucer’s Troilus and Criseyde survives in less than half as many manuscripts as Daniel’s Liber Uricrisiarum.

Daniel calls his text the Liber Uricrisiarum (the “Book about Judgments of Urine”). It is a uroscopic treatise, divided into three books: the first defines urine and instructs readers how to examine it; the second describes the twenty colors of urine; and the third outlines the various contents to be found and examined in urine. The chapter structure in each book varies between witnesses. One group of witnesses, which we call the “alpha” version, contains fewer, longer chapters, while the other, which we call the “beta” version, contains many more, shorter ones, as well as some substantial additions and many smaller revisions.

The text is primarily diagnostic in nature. In the prologue, Daniel explains that he has chosen not to describe medicines for the diseases he discusses because such a task would require a whole separate text, which he planned to write: “I promise to make a work by itself on that topic.” This other text might have been the Aaron Danielis, an herbal that is extant in two separate manuscripts. The Liber Uricrisiarum sets out to teach uroscopic diagnosis in painstaking detail for the “many and diverse men that desire to be expert in judging urines,” a subject that Daniel himself says he has never read or heard presented in English.

Despite Daniel’s decision to omit remedies for the many maladies named in the Liber Uricrisiarum, he was not shy about digressing from diagnostic rules to explain the conceptual frameworks behind those rules. His treatise includes substantial passages on such matters as the physiology of digestion and excretion, humoral theory, definitions and etymologies (occasionally also the pronunciation) of medical terms, the classification and progress of fevers and other broad disease categories, several case histories, human anatomy, pregnancy and embryology, the medieval theory of the mind and its relation to brain structure, non-uroscopic symptoms of disease (e.g. pulse, sputum, types of pain, skin color and swellings in tumors, etc.), physical astronomy, predictive astronomy (what we call astrology), and the complexities of determining leap years, the dates of Easter, and other calendric matters. The Liber Uricrisiarum is truly a medical encyclopedia, in which readers will find the full range of non-surgical medieval medical knowledge, introduced as necessary for purposes of diagnosing, understanding, and explaining human sickness.

All in all, the Liber Uricrisiarum is an eclectic compilation, blending information from Latin, Greek, and Arabic sources with Daniel’s own empirical and experiential knowledge. It is not an English translation from a single source, but a compilation of numerous sources and Daniel’s own original material.

Daniel attributes information to his sources and cites them carefully, but he also disagrees with some of their findings. At these moments of open disagreement with his predecessors, we find Daniel’s greatest originality; he tries to offer answers where he finds his authorities lacking, and uses his experience as his guide. Attributing much of his work to what he has learned from his predecessors, Daniel says, “I do not say that I write new things, but rather that I do it in a new way.” Not all of the information contained in this treatise is new, but it is all explained in a new way: that is, in English. Uroscopy already features prominently in medieval medical education and practice, but Daniel made it available in English, establishing himself as the father of the English uroscopic tradition and the Liber Uricrisiarum as the first major English source of this important field of knowledge.

Page header image: London, British Library, Harley MS 5311.