Concerning the Nature of Good, Against the Manichæans. [De Natura Boni Contra Manichæos.]  c. a.d. 405. In One Book. Written after the year 404.  It is put in the Retractations immediately after the De Actis cum Felice Manichæo , which was written about the end of the year 404.  It is one of the most argumentative of the Anti-Manichæan treatises, and so one of the most abstruse and difficult.  The lines of argument here pursued have already been employed in part in the earlier treatises.  The most interesting portions of the contents of the treatise, and the most damaging to the Manichæans, are the long extracts from Mani’s Thesaurus , and his Fundamental Epistle .—A.H.N.