A Translation of "On the Explanation of Dreams (Somniale Ioseph)" from Berlin, Staatsbibliothek, Preußischer Kulturbesitz, MS Ham. 390 f.49v Published by the Global Medieval Sourcebook
This short text is one of many so-called “dreambooks” - personal guides to dream interpretation - that flourished across Europe and Byzantium in the late Middle Ages. This particular example is a mantic alphabet known as a Somniale Ioseph, named for Joseph, the Old Testament dream interpreter. Like a similar mantic alphabet contained in the same manuscript, it is designed to be used alongside another text. A dreamer opens a book, often a psalter or prayer book, at random and stops at the first letter that they see. Turning back to the Somniale Ioseph, then, the dreamer reads the entry corresponding to that letter.
This text differs from other kinds of alphabetical dreambooks, such as the tradition known as Somniale Danielis, which listed themes and images from dreams alongside interpretations. This text instead introduces a note of chance, drawing on the long history of bibliomancy (fortune-telling with books) in the Middle Ages.
Dream interpretation was a popular pastime in the Middle Ages and hundreds of manuscript copies of dreambooks, drawn from Arabic, Byzantine, Greek, and Hebrew sources, survive alongside those written in Latin and vernacular European languages.
Read the full text in parallel translation at the Global Medieval Sourcebook: http://sourcebook.stanford.edu/text/explanation-dreams-somniale-ioseph