Earlier forms of a language

Sometimes we think of second languages only in terms of other people's languages. In literary criticism, it is also possible to think of an archaic or earlier form of a language as a second language for a writer living in a later century. For example, 1905 Nobel laureate Henryk Sienkiewicz's Trylogia (The Trilogy) - consisting of Ogniem i mieczem (With Fire and Sword, 1884), Potop (The Deluge, 1886), and Pan Wołodyjowski (Fire in the Steppe, 1888) - is noted for its use of medieval Polish in a text written in modern Polish. The study of such a literary technique could be a subcategory of multilingual criticism, perhaps known as dialectal criticism or something of that sort. In this case, the field of multilingual criticism would be very much enlarged, because we could conceivably include the use of dialect by, say, American writers such as Mark Twain and William Faulkner. As you can see, I am trying very hard to bring language back to the foreground of literary criticism, instead of the various aspects that stole center stage during the brief but exhilarating reign of 20th-century literary theory.