Syllogistic in the anon Heiberg
The anon Heiberg is a short text in five parts or Chapters: Logic, Arithmetic, Music, Geometry, Astronomy. The parts are of unequal size, the first being by far the longest.1 The edition prepared by Heiberg and published posthumously in 1929 is based on seven MSS, the earliest of which is dated to 1040. Heiberg describes a further fifteen MSS. I do not know if any more have since been discovered.
Although Heiberg’s was the first critical edition of the text, the work was not previously unknown: Chapter 1 had been published in 1600 and ascribed to Gregory;2 Chapters 2–5 had been published in 1533, and again in 1556, under the name of Michael Psellos.3 The ascription to Psellos can hardly be correct, for chronological reasons. Heiberg rejects the ascription to Gregory, apparently because the work is left anonymous in the oldest MSS. But perhaps the author was the monk Gregory Aneponymus.4 As for the date, the astronomical Chapter of the work gives 6516 as ‘the present year’ (5. 8 (p. 108. 14 H), 9 (p. 109. 9–10 H)), and the Byzantine year 6516 ran from 1 September 1007 to 31 August 1008 in the Julian calendar. The same Chapter also establishes some correlations between the Byzantine and the Egyptian calendars, and these indicate a period between 1 September and 14 December 1007.5 Hence if the five Chapters of the work form a unitary composition, the date is fixed.
Each chapter of the work has its own title (each title is an iambic trimeter); but no MS offers a title for the work as a whole. Is the piece a conjunction of five independent essays? Several MSS contain only a selection of the Chapters, which clearly had some independent circulation. Again, some
1 In Heiberg’s edn., Logic occupies some 50 pp., Arithmetic 15, Music 7, Geometry 30, Astronomy 18. References to the anonymus will be given by chapter-, section-, page- and linenumbers in Heiberg’s edn.
2 The ascription is found in two late MSS: Heiberg (1929: XV). Full bibliographical references in the Bibliography.
3 I take this information from Heiberg (1929: XIX).
4 So Benakis (1988: 5).
5 I lift all this from Taisbak (1981).