This codex contains four philosophical treatises by the English theologian and reformer John Wycliffe (also seen as John Wyclif,) (circa 1330−84). The works are The works are De tempore (also called De individuatio temporis) (On time); De ydeis [De ideis] (On divine ideas); De materia et forma (On matter and form); and De universalibus (On universals); as well as a work by an unidentified author entitled Replicacio de universalibus (Reply on the universals). According to the colophon, the manuscript was written by Jan Hus, an early proponent of ecclesiastical reform, and completed on Saint Jerome’s Day, September 30, 1398, the year Hus began his career as a professor at Prague University. The codex is the only extant large work of Hus in his own hand. It was annotated by Hus, partly in Czech, and some of the notes have a strong polemical character and are critical of the Germans. Bound in limp vellum with a reinforced spine, the manuscript is a fine example of a rapidly written and abbreviated university manuscript. Jan Hus (John Huss) was born circa 1370 in Husinec in southern Bohemia (in the present-day Czech Republic). As a preacher of the Bethlehem Chapel and rector of the philosophical faculty at the Prague University at the beginning of the 15th century, he propounded the need for a national church and the importance of the Bible as a unique authority for the belief and life of Christians. He was much influenced by Wycliffe. Hus received strong support for his ideas from Czech university students, but not from their German counterparts. Consequently, the German students left Prague and started a new university in Leipzig. Hus was convicted of heresy at the Council of Constance and burned at the stake in 1415. The manuscript was confiscated by the Swedish army in 1648, during its occupation of Prague at the conclusion of the Thirty Years’ War, and taken to Sweden.