Johannes Scotus Eriugena
Macrobius's most influential book and one of the most widely cited books of the Middle Ages was a commentary on the book "Dream of Scipio" narrated by Cicero at the end of his "Republic". The nature of the dream, in which the elder Scipio appears to his (adopted) grandson and describes the life of the good after death and the constitution of the universe from a Stoic and Neo-Platonic point of view, gave occasion for Macrobius to discourse upon the nature of the cosmos, transmitting much classical philosophy to the later Middle Ages. In astronomy, this work is noted for giving the diameter of the Sun as twice the diameter of the Earth. Of a third work "On the Differences and Similarities of the Greek and Latin Verb", we only possess an abstract by a certain Johannes, doubtfully identified with Johannes Scotus Eriugena (9th century).