Mikołaj Kruszewski

Mikołaj Habdank Kruszewski, (Russianized, Nikolay Vyacheslavovich Krushevsky, Никола́й Вячесла́вович Круше́вский) (December 18, 1851, Lutsk – November 12, 1887, Kazan[1]: 73 ) was a Polish linguist active in the Russian Empire, most significant as the co-inventor of the concept of the phoneme.

Their innovative and highly influential work was acclaimed by Roman Jakobson only about a hundred years after his time.

Kruszewski studied in the historical-philological faculty in Warsaw, teaching the Russian language to support himself.

Unfortunately his brilliant career was dramatically cut off by a grave neurological and mental illness; he had to retire the same year and died in 1887.

Alternations that belong to this category are governed by four rules: An example of the first type are those variations between particular sounds in Russian as a function of the palatalization of the preceding consonant.