How the same recherché and presumably newly-coined title, Prorrhetic, came to be given to the two very different works we have before us here and below is unknown. Completely divergent in purpose, structure, and content, the most the Prorrhetics can be said to share is, as the name suggests, an interest in medical prediction.
Once assigned, however, the names persisted. In Erotian’s census of Hippocratic writings we find among the semiotic: “Prorrhetic I and II—that it is not by Hippocrates, I shall demonstrate elsewhere.”1 Suggesting that the “it” in Erotian’s parenthetical remark refers only to book 2 is the fact that over twenty glosses from book 1 appear in the Glossary, but none from book 2.2 Six of these glosses to Prorrhetic I cite Bacchius of Tanagra,3 evidence that the work was already in the Hippocratic Collection by the third century B.C.
Although Galen regards Prorrhetic I as a mixture of both genuine and spurious Hippocratic material drawn from many sources,4 he valued the work enough to devote
Caelius Aurelianus’ Latin translation of Soranus’ Acute Diseases cites Prorrhetic I 16 by name: “For in his book entitled Prorrhetic (Praedictivo libro) he says that phrenitics drink little, are agitated by every sound, and are affected by tremor.”7
Prorrhetic I belongs to the genre of Hippocratic prognosis literature also represented by the Aphorisms and Coan Prenotions. It consists of a collection of 170 independent short prognostic or expectant chapters arranged by subject in the sections:
1–38: Phrenitis, mania, mental derangement 39–98: Bad or fatal signs 99–124: Spasms and convulsions 125–152: Haemorrhages 153–170: Swellings beside the ears.
Interest is empirical and descriptive, with virtually no theoretic content. The conditions included are weighted towards the neurological (e.g. loss of speech, deafness, delirium, coma, strabismus, headache, paralyses), although