Lojban (pronounced ) is a logical, constructed human language created by the Logical Language Group, which aims to be syntactically unambiguous. It succeeds the Loglan project.

The Logical Language Group (LLG) began developing Lojban in 1987. The LLG sought to realize Loglan's purposes and further improve the language by making it more usable and freely available (as indicated by its official full English title, Lojban: A Realization of Loglan). After a long initial period of debating and testing, the baseline was completed in 1997 and published as The Complete Lojban Language. In an interview in 2010 with The New York Times, Arika Okrent, the author of In the Land of Invented Languages, stated, "The constructed language with the most complete grammar is probably Lojban—a language created to reflect the principles of logic."

Lojban is proposed as a speakable language for communication between people of different language backgrounds, as a potential means of machine translation, and as a tool to explore the intersection between human language and software.

History Etymology The name "" means "logical language". It is a compound formed from and , which are short forms of (logic) and (language), respectively. In Lojban, a compound is called a and short forms like those (used especially to form compounds) are called .

Origins from Loglan Lojban's predecessor, Loglan, a language invented by James Cooke Brown in 1955 and later developed by The Loglan Institute, was originally conceived as a means to examine the influence of language on the speaker's thought (an assumption known as linguistic relativism).

As Brown started to claim his copyright on the language's components, bans were put on the language community's activities to stop changes to aspects of the language. In order to circumvent such control, a group of Loglan users decided to initiate a separate project, departing from the lexical basis of Loglan and reinventing the whole vocabulary, which led to the current lexicon of Lojban. To this effect, they established the Logical Language Group in 1987, based in Washington, D.C. They also won a trial over whether they could call their version of the language Loglan.Johansen, Arnt Richard. Why I like Lojban (accessed August 2007)

Divergence from Loglan The phonetic form of Lojban (root words) was created algorithmically by searching for sound patterns in words with similar meanings in world languages and by weighting those sound patterns by the number of speakers of those languages. The list of source languages used for the algorithm was limited to the six most widely spoken languages as of 1987, namely Mandarin, English, Hindi, Spanish, Russian, and Arabic. This resulted in root words being, in their phonetic form, a relatively equal mixture of English and Mandarin, with lesser influences from the other four.

Lojban also utilizes a set of evidential indicators adapted from the constructed language Láadan.Cowan, John. The Complete Lojban Language 13.11

Following the publication of The Complete Lojban Language, it was expected that the documented lexicon would be baselined, and the combination of lexicon and reference grammar would be frozen for a minimum of five years while language usage grew.Official Baseline Statement . lojban.org As scheduled, this period, which has officially been called the freeze, expired in 2002. The speakers of Lojban are now free to construct new words and idioms, and decide where the language is heading.

Contributors Below are some of the notable personalities who have contributed to the development of Lojban: Bob LeChevalier (also known as ): the founder and the president of the LLG. Robin Lee Powell (also known as ): the author of a novel-sized story, (Night Walkers). Jorge Llambías (also known as ): one of the most active Lojbanists, having done several translations. He is also a prominent figure on the mailing list, helping beginners with the language. John W. Cowan: the author of The Complete Lojban Language. Miles Forster (also known as ): a German Lojbanist who wrote the song ca pa djedi and made several large translations into Lojban. Robin Turner: a British philosopher and linguist living in Turkey, and coauthor of Lojban For Beginners. Nick Nicholas (also known as la nitcion): an Australian linguist, and coauthor of Lojban For Beginners.

Learning resources Apart from the actual practice of the language, some members of the community and LLG have been endeavoring to create various aids for the learners. The Complete Lojban Language (CLL, also known as The Red Book because of its color, and The Codex Woldemar, after its author), the definitive word on all aspects of Lojban, is one of them, finalized in 1997. Some of the projects in varying stages of completeness are: Different textbooks, presentations to help learn Lojban la muplis, an application listing Lojban sentences from the Tatoeba database with their translation to other languages

Parser: (also includes experimental grammar), (by Robin Lee Powell and Jorge Llambías), (by Richard Curnow) Database: (initial version by Jay Kominek)

Lojban's learning resources on the internet are available mainly to speakers of English, French, Spanish, Russian, Hebrew, and Esperanto, to varying degrees.Lojban materials in other languages (accessed September 2015)

Applications While the initial aim of the Loglan project was to investigate linguistic relativity, the active Lojban community recognizes additional applications for the language, including: Improved human–human communication, due to the logical and unambiguous structure and greater means of expression (use as a speakable language) Eliminating syntactic ambiguity in language Use as an educational tool Research in artificial intelligence and machine understanding Improved human–computer communication, storage ontologies, and computer translation of natural language text Research in linguistics Use as an academic language, such as in science or philosophy

Literary and cultural language Lojban is practiced by its speakers in text and voice chats.

Like most languages with few speakers, Lojban lacks much of an associated body of literature and its creative extensions have not been fully realized. For example, the true potential of its attitudinal system is considered unlikely to be drawn out until and unless children are raised entirely in a multicultural Lojban-speaking environment.Cowan, John. The Complete Lojban Language 13.16 . Also such collective or encyclopedic sources of knowledge like the Lojban Wikipedia, which may help expand the language's lexical horizon, are not very well developed.

Presently accessible Lojbanic writings are principally concentrated on Lojban.org, though there exist independent Lojbanic blog/journal sites as well. The Lojban IRC (or its archive) has a gathering of Lojbanic expressions too, but its grammatical correctness is not always guaranteed. These available materials on the internet include both original works and translations of classic pieces in the field of natural languages, ranging from poetry, short story, novel, and academic writing. Examples of works that are already available include: Alice's Adventures in Wonderland The Wonderful Wizard of Oz The Little Prince The Metamorphosis In a Grove The Book of Esther

Lojban has also been used in other media. For example, the videogame Minecraft has been partially translated into Lojban.

Means of creativity Lojban is seen by some as an intellectual device for creative writing or as having many potential aspects yet to be discovered or explored.

Dan Parmenter:

John Cowan:

Bob LeChevalier:

Programming language Constructs in programming languages have been shown to be translated to Lojban.

As with some programming languages, Lojban grammar can be parsed using parsing expression grammars.

Speakable logic Lojban has been shown to be translated in some of its parts into predicate logic. There are also analogies between Lojban and combinatory logic.

Potential machine interlingua There have been proposalsGoertzel, Ben: Potential Computational Linguistics Resources for Lojban. Self-published, March 6, 2005.Hintz, Gerold: Semantic parsing using Lojban - On the middle ground between semantic ontology and language. Technische Universität Darmstadt, August, 2014.Speer, Rob; Havasi, Catherine: Meeting the Computer Halfway: Language Processing in the Artificial Language Lojban. Massachusetts Institute of Technology, 2004. to use Lojban as an intermediate language in interlingual machine translation and knowledge representation.

Linguistic properties Lojban: is designed to express complex logical constructs precisely. has no irregularities or ambiguities in spelling and grammar (although word derivation relies on arbitrary variant forms). This gives rise to high intelligibility for computer parsing. is designed to be as culturally neutral as possible. allows highly systematic learning and use, compared to most natural languages. possesses an intricate system of indicators that effectively communicate contextual attitude or emotions.

Grammar

Phonology and orthography

Lojban has 6 vowels and 18 consonants. Some of them have, apart from the preferred/standard sounds, permitted variants intended to cover dissimilitude in pronunciation by speakers of different linguistic backgrounds.

Stress normally falls on the penultimate syllable.

There are 16 diphthongs (and no triphthongs). A distinction between diphthongs and monophthongs can be written by inserting a comma in the Latin alphabet. Vowel hiatus is also prevented by inserting an apostrophe, which usually indicates , though there are other valid realizations. For those who have trouble pronouncing certain consonant clusters, there is the option of adding vowels between them (epenthesis), as long as they differ sufficiently from the phonological vowels and are pronounced as short as possible. The resulting additional syllables are not factored into the grammar, including for the purposes of stress determination.

Lojban is written almost entirely with lower-case letters; upper-case letters are used to mark stress in words that do not fit the normal rules of stress assignment, or when whitespace is omitted.

The letters in Lojban and their respective pronunciations are shown in the table below. The IPA symbols in parentheses indicate alternative pronunciations; preferred pronunciations have no parentheses.

+ Lojban consonant phonemes Labial Alveolar Postalveolar Velar Glottal Nasal Plosive voiceless . voiced Fricative voiceless f () c () or ' () voiced v () j () Approximant Rhotic

+ Lojban vowel phonemes Front Central Back Close Mid e () y o () Open a ()

Letters Auxiliary characters IPA () () () () () () () () . Latin a b c d e f g i j k l m n o p r s t u v x y z ' . ,

In principle, Lojban may be written in any orthographic system as long as it satisfies the required regularities and unambiguities. Some of the reasons for such elasticity would be as follows: Lojban is defined by the phonemes rather than graphemes; as long as they are correctly rendered so as to maintain the Lojbanic audio-visual isomorphism, a representational system can be said to be an appropriate orthography of the language; Lojban is meant to be as culturally neutral as possible, so it is never crucial or fundamental to claim that some particular orthography of some particular languages (e.g. the Latin alphabet) should be the dominant mode.

Some Lojbanists extend this principle of cultural neutrality and assert that Lojban should have its own alphabet.Kena. Vodka-Pomme: Considerations on writing: The case of lojban (accessed August 2007)

This article uses the common Latin alphabet mode.

Morphology