Jan Baudouin de Courtenay

Jan Niecisław Ignacy Baudouin de Courtenay, also known as Ivan Alexandrovich Baudouin de Courtenay (13 March 1845 – 3 November 1929), was a Polish linguist and Slavist, best known for his theory of the phoneme and phonetic alternations. For most of his life Baudouin de Courtenay worked at Imperial Russian universities: Kazan (1874–1883), Dorpat (now Estonia) (1883–1893), Kraków (1893–1899) in Austria-Hungary, and St.

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