There is a paper on the web by Matthieu Cassin, discussing the context of the three books of the Contra Eunomium of Gregory of Nyssa. In the middle of it (p.112) he discussed the divisions in the text, as it has been transmitted. It’s fascinating stuff.
Besides the division of Book III, the different manuscripts present a list of titles for the different chapters (κεφάλαια). A large number of manuscripts indicate the chapters of Book I in the margins, proposing converging positions for them.(16) Furthermore, it is acknowledged that the chapters of Book I are by Gregory himself,(17) and I have shown that their position goes back at least to the sixth century. If this is accurate, it would be a very valuable testimony to the way Gregory understood his own text. However, the chapters of the other books are obviously not by the same hand.
(16) Matthieu Cassin, L’écriture de la polémique à la fin du IVe siècle: Grégoire de Nysse, Contre Eunome III (Thèse de doctorat, Université Paris IV – Sorbonne, 2009), vol. I, 135–7.
(17) See J. A. Röder, Gregor von Nyssa, Contra Eunomium I, 1–146, eingeleitet, übersetzt und kommentiert (Patrologia 2; Frankfurt am Main: Peter Lang, 1993), 73–4.
This is interesting, and I wish I could see the references! For if so, this is evidence of 4th century authorial chapter titles. The thesis does not seem to be online; while no-one on earth could access the Röder volume unless they live near a research library.
I will write to Dr Cassin and see if I can get a peek at his pages 135-7!
-  Matthieu Cassin«Text and context : the importance of scholarly reading. Gregory of Nyssa, Contra Eunomium», dans S. Douglas, M. Ludlow (éd.), Reading the Church Fathers, Londres, 2011, p. 109-131 et 161-165. ↩