Michael Psellos or Psellus (Greek: Μιχαὴλ Ψελλός, translit. Michaḗl Psellós, Byzantine Greek: [mixaˈil pseˈlːos]) was a Byzantine Greek monk, savant, writer, philosopher, imperial courtier, historian and music theorist. He was born in 1017 or 1018, and is believed to have died in 1078, although it has also been maintained that he remained alive until 1096. He served as a high ranking advisor to several Byzantine emperors and was instrumental in the re-positioning of power of those emperors. Source: Wikipedia (en)