The article mainly discusses hitherto perennially difficult passages from the later part of Galen’s treatise De praecognitione ad Epigenem. This ancient medical writing on prognosis deserves particular attention because it casts some light, inter alia, upon the Roman intellectual and political élite in the second century A.D. The author draws upon codex Thessalonicensis Vlatadon 14, which represents one of the internationally recognized cultural treasures of South-Eastern Europe, showing how it helps to restore the text in a significant number of areas. Interestingly, certain readings were previously known from writings of Renaissance scholars such as Janus Cornarius, Ioannes Caius Britannus, Ioannes Guinterius Andernacus and Josephus Justus Scaligerus, as well as from the deficiently investigated mediaeval Latin translation.