From the history of historical linguistics: Baudouin de Courtenay and linguistic changes

The article deals with the ideas of Jan (Ivan) Baudouin de Courtenay about the historical development of language. His critical notes on the phonetic laws are well known, but remain mostly declarative. Baudouin scrupulously studied in his practice of research regular and irregular phonetic changes, distinguishing clearly ones from anothers, trying to fi nd causes for latest ones. The ideas of some contemporary researchers about the regular/irregular language changes are also considered.