Iotacism (Greek:ἰωτακισμός,iotakismos) oritacism is the process ofvowel shift by which a number ofvowels anddiphthongs converged towards the pronunciation[i] inpost-classical Greek andModern Greek. The term "iotacism" refers to the letteriota, the original sign for[i], with which these vowels came to merge. The alternative termitacism refers to the new pronunciation of the name of the lettereta as[ˈita] after the change.
Ancient Greek had a broader range of vowels (seeAncient Greek phonology) than Modern Greek has. Eta (η) was alongopen-mid front unrounded vowel/ɛː/, andupsilon (υ) was aclose front rounded vowel/y/. Over the course of time, both vowels came to be pronounced like theclose front unrounded voweliota (ι)[i]. In addition, certaindiphthongs merged to the same pronunciation. Specifically,Epsilon-iota (ει) initially became/eː/ in Classical Greek before it later raised to (ι) while, later,omicron-iota (οι) and upsilon-iota (υι) merged with upsilon (υ). As a result of eta and upsilon being affected by iotacism, so were the respective diphthongs.
InModern Greek, the letters and digraphsι, η, υ, ει, οι, υι (rare) are all pronounced[i].
Iotacism caused some words with originally distinct pronunciations to be pronounced similarly, sometimes the cause of differences between manuscript readings in theNew Testament. For example, the upsilon ofὑμεῖς, ὑμῶνhymeis, hymōn "ye, your" (second personplural in respectivelynominative,genitive) and the eta ofἡμεῖς, ἡμῶνhēmeis, hēmōn "we, our" (first person plural in respectively nominative, genitive) could be easily confused if a lector were reading tocopyists in ascriptorium. (In fact, Modern Greek had to develop a new second-person plural, εσείς, while the first-person plural's eta was opened to epsilon, εμείς, as a result of apparent attempts to prevent it sounding like the old second-person plural.) As an example of a relatively minor (almost insignificant) source of variant readings, some ancientmanuscripts spelled words the way they sounded, such as the 4th-centuryCodex Sinaiticus, which sometimes substitutes a plain iota for the epsilon-iota digraph and sometimes does the reverse.[1]
English-speaking textual critics use the word "itacism" to refer to the phenomenon and extend it loosely for all inconsistencies of spelling involving vowels.[2]
The first demonstration of the phenomenon was made by the Dutch humanistErasmus of Rotterdam (1467-1536) in his treatise "Dialogus de recta Latini Graecique sermonis pronuntiatione" (Dialogue on the correct pronunciation of the Latin and Greek language, 1528) in which he asserted that in ancient Greek the sound of η should have been /e/, not /i/ (which is why his theory came to be called "etacism"). In support of this thesis a verse from the Athenian playwrightCratinus, one of the leading exponents ofancient Comedy, is quoted that speaks of a fool in this way: "ὁ δ'ἠλίθιος ὥσπερ πρόβατον βῆ λέγων βαδίζει" ("the fool walks making the sound "bee bee" like a sheep"); hardly could the verse "bee" be read /vi/, according to the itacistic pronunciation.[3]
Against the "Erasmian" theory came the German humanistJohannes Reuchlin (1455-1522), in whose honor theByzantine Greek pronunciation is also calledReuchlinian.