FIRMICUS MATERNUS. – A Latin writer of the 5th century AD under whose name there survive a treatise on astrology, of pagan tendencies, and a Christian apologetic work.
Of senatorial rank and Sicilian origin, after abandoning a legal career he became a writer, compiling between 334 and 337, at the suggestion of the Campanian proconsul Lollianus Mavortius, a vast treatise on astrology (*Mathesis*), in which he set forth all his knowledge of Greek and Asian astrology, drawing mainly from Manilius. It consists of eight books, the first serving as an introduction; in laying the foundations of the science here, Firmicus strives, despite recognizing the difficulty, to give astrology a more secure human meaning by linking it with morality. With the decline of astrological science, the practical interest that for many centuries, and especially in the Middle Ages, had led to the study of the treatise ceased, and it remains of interest only for the allusions it contains to the morality of the time and as a historical document.
In the other work, *De errore profanarum religionum*, the Christian content has given rise to a long-standing controversy due to the difficulty—now largely dismissed—of supposing that the author of the astrological treatise converted within the ten years separating the two works. In the *De errore*, published between 346 and 350, the usual arguments of apologetics are not enriched with original polemical motifs but instead are infused with a vehemence hitherto unparalleled. The author does not seek the eradication of paganism through teaching and conversion but through the intervention of secular forces, namely the emperors Constantius and Constans, to whom the work is addressed, invoking their divinely entrusted mission, which will be rewarded with heavenly blessing and the confiscation of pagan cult images. The book is divided into two parts: the first attacks the religions of nature and the mystery cults; in