One of my interests is language, especially second-language acquisitation. I am also interested by the phenomenon of polyglots. Some polyglots are able to speak ten or more languages. I have corresponded with one, Dr Alexander Argüelles, who has taught himself some 41 languages all of which he can read, write and speak with varying levels of accuracy. He has also written some very good textbooks on the Korean language. Until fairly recently, there weren’t much good resources for the Korean language. He knows Korean well enough to where he was able to write, in Korean, a guide for conjugating French verbs.
The late Dr. Kató Lomb (1909-2003) was one Hungary’s most accomplished polyglots. Dr. Lomb spoke 16 languages fluently, most of which she acquired in her 30s and 40s. She was fluent in both Chinese and Japanese, in addition to a wide variety of European languages. She was a translator for the Hungarian government and also translated literature and technical articles from six languages as a professional translator. She published a book, now sadly out of print, called Így tanulok nyelveket or How I Learn Languages. For languages with relatively few speakers, such as Hungarian or Finnish, some knowledge of another language is necessary. Unlike speakers of other languages such as Croatian or Slovak, there aren’t any languages closely related to Finnish or Hungarian. While Hungarian and Finnish do belong to the same language family, the vocabulary differs to a huge extent. It isn’t like Swedish and Norwegian, both of whom are very close to each other. Europeans do learn other languages, but most do not learn them on the level of Dr. Lomb or Dr. Argüelles.
Those who are interested in learning languages may well appreciate this overview of the late Dr. Lomb’s method of learning.
Wikipedia also has a more expanded biography of Dr. Kató Lomb.