I just realized that although I chose a Lojban name for this blog, I haven't written much about it.
Lojban (and its predecessor/competitor Loglan) was conceived as a language that would fit more or less within the realm of human language universals, but that at the same time would be syntactically unambiguous, and its semantics would be "based on" predicate calculus. If some version of the Sapir-Whorf Hypothesis is true, then maybe learning a language based on predicate calculus would cause you to be a more logical thinker.
The Lojban experiment has been a success in the sense that a complete, usable language was developed, and there are a community of speakers doing translations, original writing, and holding conversations in it. I participated in the Lojban community in the mid 90s, and I found learning it to be an interesting mental exercise for several reasons:
- It required some distinctions that are not habitually made in English; for example there are 14 logical connectives to choose from, plus some non-logical connectives. At first you find yourself drawing truth tables to figure these things out, but eventually they come more naturally as you use them enough.
- Other things were easier than English. As in Japanese, in Lojban you can often elide important words, with the hole being implicitly filled in with "whatever is obvious to both speakers".
- There was an incredibly fun and productive word construction process, where you'd take these three-letter word bricks and glue them together to make compounds. German's got nothing on Lojban.
- The language is excessively rich in hundreds of little words that approximately fill the role of prepositions. Some of these were thought up rather cavalierly for theoretical reasons or out of a sense of completeness, to fill out a pattern of similar words, so while their meaning was clear, it was not always clear when they would be useful. Coming up with plausible usages and trying to nonchalantly work them into forum conversations was great fun.
- There was also a composable vocabulary of short words made exclusively of vowels and glottal stops, called "attitudinals", representing emotions. You could often get your point across by just expressing how you felt about it, and let the content be implied.
- While Lojban borrowed some concepts from propositional logic to great benefit, in the end I don't think it would be fair to say Lojban was "based on" logic. To me that would mean that language structures would be defined in terms of a simpler and pre-existing formal logic already known and understood by logicians. As it was, we had endless arguments about how to correctly translate example sentences from Quine, like, say, "I want a sloop" in the case where there is not a particular sloop you have your eye on. I think problems of this sort went pretty deep, and probably the language should have been designed from the ground up around a particular theory of meaning, right or wrong, rather than making up a grammar and arguing about what it meant later.
- The community was fascinated with navel-gazing issues of this sort, which was highly addictive but not very fruitful in my opinion. It was educational and thought provoking for me, but I did not have the formal logic/philosophy of language background to contribute as productively as I wished I could have.