Sextus Empiricus (c. 160-210 AD), was a physician and philosopher, and has been variously reported to have lived in Alexandria, Rome, or Athens. His philosophical work is the most complete surviving account of ancient Greek and Roman skepticism.
In his medical work, tradition maintains that he belonged to the "empiric school", as reflected by his name. However, at least twice in his writings, Sextus seems to place himself closer to the "methodic school", as his philosophical views imply.
Sextus Empiricus's three known works are the Outlines of Pyrrhonism and two distinct works preserved under the same title, Against the Mathematicians (Adversus Mathematicos), one of which is probably incomplete.
The first six books of Against the Mathematicians are commonly known as Against the Professors, but each book also has a traditional title (Against the Grammarians (book I), Against the Rhetoricians (book II), Against the Geometricians (book III), Against the Arithmeticians (book IV), Against the Astrologers (book V), Against the Musicians (book VI). It is widely believed, with perhaps the exception of Sextus scholar Richard Bett, that this is Sextus's latest and most mature work.
Books VII-XI of Against the Mathematicians form an incomplete whole; scholars believe that at least one, but possibly as many as five books, are missing from the beginning of the work that was originally entitled Skeptical Treatises (Skeptika Hupomnēmata). The extant books have the traditional titles Against the Logicians (books VII-VIII), Against the Physicists (books IX-X), and Against the Ethicists (book XI). Against the Mathematicians VII-XI is sometimes distinguished from Against the Mathematicians I-VI by giving it the title Against the Dogmatists (in which case Against the Logicians are called books I-II, Against the Physicists are called books III-IV, and Against the Ethicists is called book V, despite the fact that it is commonly believed that the beginning of the work is missing and it is not known how many books might have preceded the extant books).
Note that none of these titles except Against the Mathematicians and Outlines of Pyrrhonism, are found in the manuscripts.