Lojban is almost certainly one of the dorkiest things in existence. It's
nevertheless pretty interesting.
The obsession with constructing a perfect language is an old
one.
There's a wonderful book about attempts to discover or
invent a perfect language—it's written by Umberto Eco
and called La ricerca
della lingua perfetta nella cultura europea, which was
translated into English as The Search for the Perfect
Language.
Languages like Hildegaard von Bingen's Lingua Ignota or
Jon Wilkins' Real Chracter are different approaches to
building a language which is somehow perfect or sublime.
Other constructed languages have attempted to be optimal in
some particular respect—for example, Esperanto and Volapük,
for example, being culturally
neutral languages
At least, nominally culturally neutral.
designed for international communication.
The Loglan language—a predecessor of Lojban—grew out of a
similar urge, but instead of being philosophically perfect
or internationally optimal, it was designed to be perfectly
grammatically logical and unambiguous.
What this means is sometimes misunderstood: the fact that
Loglan (or Lojban) is "logical" does not, for example, mean
that wordplay is impossible in the language, or that every
statement is perfectly precise. It does, however, mean that
a given statement can be perfectly precise. The grammar
of the language is unambiguous, which means there are no ambiguous
sentences like the English sentence, "John saw the man with the
binoculars", and indeed, the book that describes Loglan takes
great pleasure in giving a Loglan translation of every possible
interpretation of the English phrase, "the pretty little girls'
school." The structure of a given phrase is rigorously defined.
However, this doesn't mean (for example) that you can only say things
which are true, or unambiguous: you can still easily produce
nonsense phrases, or be semantically ambiguous, in much
the same way that you can form nonsense syllogisms or unclear
mathematical equations.
Over time, Loglan's designer—writer and sociologist James Cooke
Brown—attempted to enforce copyright over the language, which
led to part of the Loglan enthusiast community creating their own alternate
version of the language, unencumbered by copyright
claims. This language is, of course, Lojban.
The creators of this new language built up the
vocabulary by an algorithm which ingested and spat out roots from the
six most widely-spoken languages at the time, which resulted in
words which are very faintly similar to existing vocabulary but
only in the barest, most subtly evocative sense. The new language
also added new grammatical features on top of Loglan borrowed from
other sources.
In contrast to most natural languages, which develop around word
classes like nouns or verbs or adjectives, Lojban is primarily
concerned with predicates, which it calls brivla.
Lojban reference material tends to quickly start using
exclusively Lojban words for grammatical concepts, which )
find is one of the most tedious and unfortunate parts of
the material. You very quickly come across sentences
like, "The rafsi of these gismu combine to form this
bridi," which is precise and convenient for avid learners,
but opaque and difficult for casual readers.
A predicate is a function which takes arguments
and produces either truth or falsehood: by convention,
we assume that an expression involving a predicate is expressed
in such a way that it results in truth.
We can express predicates in the same way we express most
mathematical functions: for example, we might
construct a predicate \(\textit{is-a-cat}\) which takes
an entity and tells us whether or not it is a cat. The
following formula (using the \(\land\) operator to represent
and and the \(\neg\) operator to represent
not) expresses that Garfield is a cat while
Jon is not a cat:
$$
\textit{is-a-cat}(\textit{garfield})
\land \neg \textit{is-a-cat}(\textit{jon})
$$
We could also build up predicates that operate over multiple
arguments:
for example, we could use \(\textit{sees}(x, y)\) to express that
\(x\) is looking at \(y\).
$$
\textit{sees}(\textit{garfield}, \textit{jon})
$$
We can also combine ideas that share variables in order to
express more complicated concepts: for example, if we know that
Garfield is seeing a cat, but we don't have
a name for that particular cat, we can express that using
our mathematical notation as well by introducing a dummy
variable:
$$
\textit{sees}(\textit{garfield}, x) \land
\textit{is-a-cat}(x)
$$
The Lojban language builds off of predicate logic like this, but provides a
system for speaking these kind of formulae aloud. Instead of
\(\textit{is-a-cat}(\textit{that-thing})\), we use
the word
The words that appear in this colorthat is, #993366 here will have tooltips, so
you can easily recall the meaning of each word.
tathat to stand in for \(\textit{that-thing}\),
and we express the predicate \(\textit{is-a-cat}\) by
the word mlatuis-a-cat.
So, we can express our sentence:
tathat mlatu.is-a-cat
"That is a cat."
We can also use proper nouns like "Garfield" or "Jon",
but Lojban insists that, for clarity, we explicitly indicate
which words are proper nouns: they must be preceeded
by the word lathe-one-named, must be spelled using Lojban's phonetic
conventions, and must end in a consonant. This ensures that
proper nouns are easily distinguishable from other classes of
words.
It is likely for this reason that nobody has attempted to translate
the works of Abbott and Costello into Lojban.
lathe-one-named garfildGarfield mlatu.is-a-cat
"Garfield is a cat."
The arguments given to predicates are ordered, so for a
predicate of more than one argument, we can list the
arguments in the correct order. Using the Lojban predicate
viskasees, which is analogous to our
predicate \(\textit{sees}(x, y)\):
lathe-one-named garfildGarfield viskasees lathe-one-named djan.Jon
"Garfield sees Jon."
What if we want to express something like,
"Garfield sees the cat," though? Well, we could say
something like
lathe-one-named garfildGarfield viskasees ta.that tathat mlatu.is-a-cat
"Garfield sees that thing. That thing is a cat."
But even though it's logically similar to what we want to
express, it's awkward linguistically. To that end, Lojban
lets us turn a predicate into a "thing" using the article
lothat-which, which means something like,
"The thing such that [a predicate] is true." Therefore,
the phrase lothat-which mlatuis-a-cat means, "the thing such that it is
a cat," or more idiomatically, "the cat."
lathe-one-named garfildGarfield viskasees lothe-one-which mlatu.is-a-cat
"Garfield sees the cat."
If we don't need or want to specify an argument to some
predicate, we can supply it with the word zo'e[unspecified], which
stands in for something that's not relevant to the
current discourse. Thus, we can translate
the more vague statement, "Garfield sees something," as
lathe-one-named garfildGarfield viskasees zo'e.something unspecified
"Garfield sees something unspecified."
If the word zo'e[unspecified] comes at the end of a sentence, we
can safely omit it; otherwise, predicates with a large number of
arguments would always end in a tedious string of
zo'e[unspecified] zo'e[unspecified again] zo'e[this one is unspecified too].
In fact, I've already been doing this without mentioning it:
the predicate mlatuis-a-cat takes not one but two
arguments—x mlatux1 is a cat of species x2 y
means that x is a cat of species y—and
viskasees takes three
arguments—x viskax1 sees x2 under x3 y z means
that x sees y in the condition z. Some
predicates take as many as five arguments:
for example, klamacomes/goes, according to the standard Lojban
reference documents, means:
x1 comes or goes to destination x2 from origin x3 via route x4 using means or vehicle x5
That means we can express the sentence, "Jon is coming," as:
lathe-one-named djanJon klamacomes zo'e[to somewhere unspecified] zo'e[from somewhere unspecified] zo'e[by an unspecified route] zo'e[using an unspecified vehicle].
"John is coming."
or, more concisely, as
lathe-one-named djanJon klamacomes.
"John is coming."
We can also rearrange the order of arguments to a predicate:
the word se[swap x1 and x2] is used to swap the first two arguments to
a predicate, so that
lathe-one-named garfildGarfield viskasees lathe-one-named djanJon.
"Garfield sees John."
is identical in meaning…although perhaps not in emphasis! to
lathe-one-named djanJon se viskais seen by lathe-one-named garfildGarfield.
"John is seen by Garfield."
We can use those argument-swapping words with lothat-which, as well:
lothat-which viskasees means "the one seeing" or "the see-er",
while lothat-which se[swap x1 and x2] viskasees means
"the one being seen." This is a convenient way of building up
a very large amount of vocabulary: from the five argument positions
of the word klamacomes/goes, we can derive five "nouns":
lothat-which klamagoes "the go-er",
lothat-which seswap x1 and x2 klamagoes "the destination",
lothat-which teswap x1 and x3 klamagoes "the origin",
lothat-which veswap x1 and x4 klamagoes "the route", and
lothat-which xeswap x1 and x5 klamagoes "the means of transportation".
Now we have the grammar necessary to tell relatively basic
and banal children's stories:
lathe-one-named djanJon viskasees lathe-one-named garfildGarfield. lothat-which mlatuis-a-cat ciskaeats lathe-one-named lazaniaslasagna.
"Jon sees Garfield. The cat eats the lasagna."
Lojban of course is more than just what I've introduced
above: tenses,
In fact, I've been acting as though these sentences are
in the present tense, but by default Lojban sentences
do not specify time at all: they could contextually
be interpreted as past, present, or future.
pronouns, compound clauses, and so forth. Lojban also
has a relatively large set of "discursives", which are
words used to structure conversations in a rich and
descriptive way, and several other interesting features.
But I've shown the three major components of the Lojban
language: proper nouns, structure words like
lothat-which and se[swap x1 and x2],
and predicates, which are the principal
distinguishing feature of Lojban.
