A correspondent writes to ask if Latin is a dead language or not. She goes on: 'Obviously there are no native Latin speakers born any more, but on the other hand there are a number of people who can speak it, or at least understand it...'
The distinction between life and death can be a bit fuzzy, when applied to language. The essential difference is that living languages change, dead ones don't. Just because I study a dead language and get to understand it, or even speak it aloud, does not make it come alive, in that sense. It would come alive only when speakers use it in interaction and adapt it to meet their current needs. Several dead languages (in the sense that their last native speaker died some time ago) have been resurrected in that way, as with Kaurna in Australia. Sometimes there is a tradition linking the present with the past, as with Cornish. But the crucial thing, to say that a language is alive, is to find it changing and growing - new vocabulary, in particular, to express present-day notions, and new variant forms (accents, dialects), to express different identities. Latin is alive in that sense. The 'most alive' languages have native speakers and transmit from parent to child between generations. Latin is plainly not alive in that sense.
Latin is an interesting case, therefore. Many people study it as a dead language, as a way in to an ancient literature and history. On the other hand, it still has live status as a language of real interaction in the Roman Catholic church. The Lexicon Recentis Latinitatis came out a few years ago - over 700 pages of modern vocabulary. I have ingenious translations of Winnie the Pooh, Peanuts, and other texts, so plainly many people are actively concerned with revitalization. How much use is actually being made of the language is unclear, but it certainly suggests there's life in the old language yet.
Anyone interested in the history of Latin as a language should read Nicholas Ostler excellent Ad Infinitum: A Biography of Latin.