The evolution of Action Nouns in -išn between Middle Persian and New Persian

Middle Persian Action Nouns in ‑išn have become ‑eš in Standard Contemporary Persian. In Early New Persian (8th–12th centuries), there are some occurrences of ‑išn. The present paper focuses on the evolution of these words, especially ravišn “method” in the name of the vizier Rāst-Ravišn in the Siyāsat-nāma “The Book of Government” by Nizām al-Mulk, which was reinterpreted as Rāst-Raušan. The causes of this misunderstanding are numerous and illustrate well Joseph’s theory of multiple causes in language change (2013). They are examined here from a phonological, syntactical, and lexicological perspective. In this regard, this paper further investigates the occurrences of other nouns ending in ‑išn, ‑išt, and ‑iš in Early New Persian and Early Judaeo-Persian (8th–12th centuries). Some vocalisations in ‑išǝn, the replacement by ‑išt, and the dropping of the final consonant are different evolutions, offering a clue as to the presence of a true problem with the pronunciation of the suffix ‑išn. Concerning the specific word ravišn in the vizier’s name, the Noun – Adjective order that entirely replaces the ancient Adjective – Noun order, along with the likely increase in copulative compounds, also have to be taken into account