"All characters begin with the common tongue and their alignment language. Some classes grant further languages, and characters with high intelligence receive additional languages. Additional languages can be chosen at the Labyrinth Lord’s discretion. In general, any races or monsters capable of language have their own language." -- Labyrinth Lord p.14
This post isn't about alignment languages. In every campaign I've ever run I just ignore those.* No, it's about those additional languages gained from having an above-average INT score.
In general, I tend to ignore the issue of languages in the game altogether -- not out of any theory or moral principle, it just tends to end up that way. I suppose one reason for this is that I rarely use any of the standard monstrous races. Another reason is that I simply can't be bothered with it -- it's generally much more fun (for me) if players can just talk to the stuff they encounter. A matter of taste, of course.
But anyway, I've recently instigated a small house rule which is (I think) simple, elegant and effective, and which I wanted to share.
This is it:
"In place of an extra language, a character with high INT can choose an area of special knowledge or academic training."
This can be whatever the player wants (with the LL's approval, of course). Things like: alchemy, medicine, herbalism, history, fine arts, ancient technology, astronomy, philosophy, etc.
There is no specific rules mechanic tied to these areas of specialist knowledge, they are simply used in situations of improvisational ruling to determine what a character might know. In this sense they work similarly to "secondary skills" (in AD&D / AEC), but have a more intellectual / academic bent.
* Does anyone ever use alignment languages? I've contemplated coming up with an in-game explanation for them, but have never got around to running a campaign with such ideas in place.