Dating
In his extant writings, Pappus gives no indication of the date of the authors whose treatises he makes use of, or of the time (but see below) at which he himself wrote. If we had no other information, we should only know that he was later than Ptolemy (died c. 168 AD), whom he quotes, and earlier than Proclus (born c. 411 AD), who quotes him.
The Suda (a 10th century Byzantine Greek encyclopedia of known inaccuracy) states that Pappus was of the same age as Theon of Alexandria, who flourished in the reign of Emperor Theodosius I (372–395 AD). A different date is given by a marginal note to a late 10th century manuscript (a copy of a chronological table by the same Theon), which states, next to an entry on Emperor Diocletian (reigned 284–305 AD), that "at that time wrote Pappus".
However, a real date comes from the dating of a solar eclipse mentioned by Pappus himself, when in his commentary on the Almagest he calculates "the place and time of conjunction which gave rise to the eclipse in Tybi in 1068 after Nabonassar". This works out as October 18, 320 AD, and so we can finally say that Pappus flourished c. 320 AD.
Read more about this topic: Pappus Of Alexandria
Famous quotes containing the word dating:
“We go on dating from Cold Fridays and Great Snows; but a little colder Friday, or greater snow would put a period to man’s existence on the globe.”
—Henry David Thoreau (1817–1862)