Aelius Donatus

Aelius Donatus (English pronunciation: /doʊˈneɪtəs/; fl. mid-fourth century AD) was a Roman grammarian and teacher of rhetoric. St. Jerome states in Contra Rufinum 1.16 that Donatus was his tutor.

He was the author of a number of professional works, of which several are extant:

Donatus was a proponent of an early system of punctuation, consisting of dots placed in three successively higher positions to indicate successively longer pauses, roughly equivalent to the modern comma, colon, and full stop. This system remained current through the seventh century, when a more refined system due to Isidore of Seville gained prominence.

Donatus invented the system whereby a play is made up of three separate parts: protasis, epitasis, and catastasis.

Aelius Donatus should not be confused with Tiberius Claudius Donatus, also the author of a commentary (Interpretationes) on the Aeneid, who lived about 50 years later.

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