He was not only one of the foremost scholars of his day in the physical sciences, as well as in Aristotelian and Platonic philosophies, but also a renowned computist and teacher of the Neoplatonic philosopher Iamblichus.
Prior to becoming one of the great lights of the Church, Anatolius enjoyed considerable prestige at Alexandria while working as a senator.
This work seems to have been copied by the author of the curious writing entitled Theologoumena arithmetica, a Neoplatonic treatise heavily influenced by Pythagoreanism, uncertainly attributed to Iamblichus ─ though not written in his style, it is a discussion of each of the first ten natural numerals that mixes accounts of formal arithmetical properties with mystical philosophical analysis.
[8] His famous 19-year Paschal cycle has survived in seven different complete medieval manuscripts of the Latin text De ratione paschali.
[11][12][13] Therefore, Anatolius can be considered to be the founder of the new Alexandrian computus paschalis which half a century after began with the active construction of the second version of the Metonic 19-year lunar cycle, which itself or a close variant of which ultimately would prevail throughout Christendom for a long time (until the year 1582, when the Julian calendar was replaced with the Gregorian calendar).
[26] Considering that only around AD 400 Annianus obtained his classical Alexandrian version of the Metonic 19-year lunar cycle by adapting Theophilus’ 19-year lunar cycle by moving its saltus 1 year forward by replacing its date 6 April by 5 April,[27] the Catholic Encyclopedia concludes that the compilation in question dates from the fifth century.
Of course, this does not exclude that the (in principle tentative) version constructed in the first quarter of the fourth century could be, by chance, equal to Annianus’ ultimately definitive one.
In any case, this possible equality cannot be assured in the way Neugebauer tried to prove it, because the particular Metonic 19-year lunar cycle of the not-dated manuscript concerning AD 311-369 he staged,[28] could have been obtained afterwards by simply extrapolating from the fifth century 7980-year framework.