Lojban (/LOZH-bahn/) is a constructed language. Originally called 'Loglan' by project founder Dr. James Cooke Brown, who started the language development in 1955, the goals for the language were first described in the article Loglan in Scientific American, June 1960. Made well-known by that article and by occasional references in science fiction and computer publications, Loglan/Lojban has been built over four decades by dozens of workers and hundreds of supporters, led since 1987 by The Logical Language Group.
There are many artificial languages, but Loglan/Lojban has been engineered to make it unique in several ways. The following are the main features of Lojban:
Lojban is designed to be used by people in communication with each other, and possibly in the future with computers.
Lojban is designed to be culturally neutral.
Lojban grammar is based on the principles of logic.
Lojban has an unambiguous grammar.
Lojban has phonetic spelling, and sounds can be divided into words in only one way.
Lojban is simple compared to natural languages; it is easy to learn.
Lojban's 1350 root words can be easily combined to form a vocabulary of millions of words.
Lojban is regular; the rules of the language don't have exceptions.
Lojban attempts to remove restrictions on creative and clear thought and communication.
Lojban has a variety of uses, ranging from creative to scientific, from theoretical to practical.
The following sections examine each of these points, while answering the questions most often asked about Lojban.
Lojban was originally designed to support research on a concept known as the Sapir–Whorf hypothesis. Simply expressed, this hypothesis states that the structure of a language constrains the thinking of people using that language. Lojban allows the full expressive capability of a natural language, but differs in structure from other languages in major ways. This allows it to be used as a test vehicle for scientists studying the relationships between language, thought, and culture. If you are reading this as part of the introductory booklet, further discussion of these issues can be found in the section Technical Descriptions.
Yes, several. Due to its unambiguous grammar and simple structure, it also can be easily parsed (broken down for analysis) by computers, making it possible for Lojban to be used in the future for computer–human interaction, and perhaps conversation. Lojban's structure is similar to existing artificial intelligence (AI) programming languages, and it may become be a most powerful adjunct to AI research, especially in the storing and processing of data about the world and people's conceptions of it. There are also linguists interested in Lojban's potential as an intermediate language in computer-aided translation of natural languages; and Lojban is of interest as a potential stepping-stone for students learning other languages. Because Lojban was designed to be culturally neutral, and has a powerful vocabulary easily learned by people of different language origins, some are interested in Lojban's potential as an international language. These are only the beginnings of the Lojban applications that will be developed in the future.
Lojban was designed as a human language, and not as a computer language. It is therefore intended for use in conversation, reading, writing, and thinking. However, since Lojban can be processed by a computer much more easily than can a natural language, it is only a matter of time before Lojban-based computer applications are developed. Learning and using Lojban doesn't require you to know anything about computers or to talk like one.
Lojban uses letters of the Roman alphabet to represent its 6 vowels and 17 consonants. The Lojban character set uses only standard typewriter/computer keyboard keys; capitalization is used rarely, and only to indicate unusual stress in the pronunciation of names. Punctuation is spoken as words. The written language corresponds exactly to the sounds of the spoken language; spelling is phonetic and unambiguous, and the flowing sounds of the language break down into words in only one possible way. These features make computer speech recognition and transcription more practical. Learning to pronounce and spell Lojban is trivial.
Lojban has a smooth, rhythmic sound, somewhat like Italian. However, its consonants create a fullness and power found in Slavic languages like Russian, and the large number of vowel pairs impart a hint of Chinese, Polynesian, and other Oriental languages, though without the tones that make many of those languages difficult for others to learn.
Because there are no idioms to shorten expressions, a Lojban text can be longer than the corresponding colloquial English text. The unambiguous linguistic structures that result are a major benefit that makes this worthwhile; and Lojban has constructions of its own that are rather more succinct than their equivalents in English (such as logic-specific formulations, and expressions of attitude.) Moreover, much of the disambiguating machinery of Lojban is optional; you use them only when you need to use them.
As an example of Lojban, Occam's Razor ("The simplest explanation is usually the best") may be translated as:
The apostrophe is pronounced like a short, breathy 'h', and is used to clearly separate the two adjacent vowels for a listener, without requiring a pause between them.roda poi velcki cu so'eroi ke ganai saprai gi xagrai
/row-dah poy VELSH-kee shoo so-heh-roy keh GAH-nye SAHP-rye ghee KHAH-grye/
All somethings which-are explanations mostly-are (if superlatively-simple then superlatively-good).
(If you are reading this text in the What is Lojban? booklet, a full pronunciation key is available in the Overview of Lojban Grammar.)
'Grammar' is a word with painful memories for many of us. But though Lojban grammar seems strange at first sight, it is actually quite simple. It is based on a system called predicate logic, which states that in any sentence you have a relationship (selbri in Lojban) between one or more arguments (sumti). An argument can be a thing, event, quality or just about anything. To give an example, the English sentence
has a relation adore, between two arguments, Chris and Pat. In Lojban this would beChris adores Pat
or, if you prefer,la kris. prami la pat.
(The full stops mean that you have to pause slightly to separate the words — anythingelseinLojbancanberuntogetherwithoutbeingmisunderstood).la kris. la pat. prami
You might be thinking "Well in that case a relationship is a verb and an argument is a noun, so why bother with special terminology like selbri and whatnot?" However, in Lojban Chris's feelings about Pat might be described like this:
la pat. melbi
Pat is beautiful.
In English you have a verb ('doing word'), is, and an adjective ('describing word'), beautiful. In Turkish, you would say Pat güzel, which is a noun and an adjective, with no verb required. In Chinese you would use meili, a 'stative verb' — but enough! In Lojban you don't need all these language-specific notions.
Now, if there are no nouns, verbs, subjects or objects in Lojban, how do we know that la kris. la pat. prami means that Chris adores Pat and not the other way? Different languages handle this problem differently. In English it is done with word order, and when that isn't enough, with prepositions (words like at, from, to, with and so on). In other languages, like Latin or Turkish, it's done by changing the form of the words, e.g. Pat'i Chris sever in Turkish means "Chris loves Pat", not "Pat loves Chris."
In Lojban, the order in which arguments appear is built in to the meaning of the word. For example, the word dunda means give, but its full meaning is:
x1 gives x2 to x3
So mi pu dunda le cukta le ninmu means "I gave the book to the woman", not "I gave the woman to the book").
The important point is that Lojban has a lot of what we would call 'grammar', but nearly all of this is contained in the cmavo (structure words), and you can use as many or as few of them as you want.
In Lojban, it is equally easy to speak of something as being an action as it is to speak of it as being a state of existence. The distinction between the two can be ignored, or can be explicitly expressed in a variety of ways:
by associating concepts in tanru metaphors (combinations of selbri into single expressions giving novel meanings), involving words like gasnu ('do'), zasti ('exist'), zukte ('act with purpose');
with a variety of 'operators' (cmavo) dealing with abstractions such as events, states, properties, amounts, ideas, experience, and truth;
or with four pre-defined varieties of causality (others can be developed through tanru metaphor).
A major benefit of using a predicate grammar is that Lojban doesn't have inflections and declensions on nouns, verbs, and adjectives. Most natural languages have evolved such variations to reduce ambiguity as to how words are related in a sentence. Language change has made these inflections and declensions highly irregular and thus difficult to learn. Lojban uses the simple but flexible predicate relationship to erase both the irregularity and the declensions.
Tense and location markers (inflections), adverbs, and prepositions are combined into one part of speech. New preposition-like forms can be built at will from predicates; these allow the user to expand upon a sentence by attaching and relating arguments not normally included in the meaning of a word.
Numbers and quantifiers are conceptually expanded from natural languages. Many, enough, too much, a few, and at least are among concepts that are expressed as numbers in Lojban. Thus "it costs $3.95" and "it costs too much" are grammatically identical, and one can talk of being "enough-th in line" for tickets to a sellout movie. Core concepts of logic, mathematics, and science are built into the root vocabulary. They enhance discussion of those topics, and are surprisingly useful in ordinary speech, too.
Predicate logic can express a wide variety of human thought; Lojban also has non-logical constructs that do not affect or obscure the logical structure, allowing communications that are not amenable to logical analysis. For example, Lojban has a full set of emotional indicators, which are similar to such interjections in English as Oh!, Aha!, and Wheee!, but each has a specific meaning. Similarly, Lojban has indicators of the speaker's relationship to what is said (whether it is hearsay, direct observation, logical deduction, etc.) similar to those found in some Native American languages.
Lojban supports metalinguistic discussion about the sentences being spoken while remaining unambiguous. Lojban also supports a variety of 'tense' logic that allows one to be extremely specific about time and space (and space–time) relationships. A substantial portion of Lojban's grammar is designed to support unambiguous statement of mathematical expressions and relations in a manner compatible both with international usage and the rest of Lojban's grammar.
Lojban 'parts of speech' are convertible from one to another by using short structure words (called cmavo). One can make numbers serve as nouns or verbs, or invent new numbers and prepositions. Lojban removes many of the constraints on human thought, while preserving tight control on structural syntax.
Lojban is actually much simpler than natural languages. It is only slightly more complex in its grammar than the current generation of computer languages (such as C++ and Perl). Lojban seems complex only because the varieties of human thought are complex, and Lojban is designed to minimize constraints on those thoughts. Lojban text can appear longer and more complex due to its lack of idiom, its complete explicitness of logical structure, and most importantly, its unfamiliarity. On the other hand, conversational speech uses less than half of the possible grammatical structures, leaving the rest for writing and for other circumstances when one is likely to take time to carefully formulate exact logical phrasings.
Lojban's pronunciation, spelling, word formation, and grammar rules are fixed, and the language is free of exceptions to these rules. Such exceptions are the bane of learning to speak a natural language correctly. Without the burden of ambiguity, Lojban users can be precise and specific more easily than in other languages.
Because Lojban's grammar is simple, it is easier to learn than other languages. Using flashcard-like techniques, a working vocabulary including the complete set of 1350 root words can take 8–12 weeks of study at 1 hour per day. It is by no means uncommon for people who embark on learning Lojban to be able to write grammatical Lojban within a few days, and to hold at least a limited conversation within a few weeks. Natural languages, especially English, take several years to learn to a comparable level of skill.
The available Lojban teaching materials are so structured that you can learn the language without classroom instruction or a close community of speakers. Communication practice with others is needed to achieve fluency, but you can start using the language as you achieve proficiency.
Lojban has an unambiguous grammar (proven by computer analysis of a formal grammar), pronunciation, and morphology (word forms). In practice this means that the person who reads or hears a Lojban sentence is never in doubt as to what words it contains or what roles they play in the sentence. This is true even if the words are unfamiliar, so long as the spelling and grammar rules are known. Lojban has no words that sound alike but have different meanings (like herd and heard), that have multiple unrelated meanings (set), or that differ only in punctuation but not in sound (like the abominable its and it's). There is never any doubt about where words begin and end (if you hear cargo ship, do you hear two words or three?) Most important, the function of each word is inescapably clear; there is nothing like the English sentence Time flies like an arrow, in which any of the first three words could be the verb.
Lojban is not entirely unambiguous, of course; human beings occasionally desire to be ambiguous in their expressions. In Lojban, this ambiguity is limited to semantics, tanru metaphor, and intentional omission of information (ellipsis).
Semantic ambiguity results because words in natural languages represent families of concepts rather than individual meanings. These meanings often have only weak semantic relationships to each other (the English word run is a good example.) In addition, each individual's personal experiences provide emotional connotations to words. By providing a fresh, culturally-neutral start, Lojban attempts to minimize the transference of these associations as people learn the language. Most Lojban words do not much resemble corresponding words in other languages; the differences aid in making this fresh start possible.
Lojban's powerful tanru (combinations of selbri into novel concepts) and word-building features make it easy to make fine distinctions between concepts. This discourages the tendency for individual words to acquire families of meanings. Lojban's tanru metaphors are themselves ambiguous; they specify a relationship between concepts, but not what the relationship is. That relationship can be made explicit using unambiguous logical constructs if necessary, or can be left vague, as the speaker typically desires. Similarly, portions of the logical structure of a Lojban expression can be omitted, greatly simplifying the expression while causing some ambiguity. Unlike in the natural languages, though, this ambiguity is readily identified by a reader or listener. Thus all ambiguity in Lojban is constrained and recognizable, and can be clarified as necessary by further interaction.
This precision in no way confines the meaning of a Lojban sentence. It is possible to be fanciful or ridiculous, to tell lies, or to be misunderstood. You can be very specific, or you can be intentionally vague. Your hearer may not understand what you meant, but will always understand what you said.
Most humor arises from situation and character and is as funny in Lojban as in any language. Humor based on word play, of course, is language-dependent. Lojban has no homonyms, and hence no simple puns; puns derived from similar sounds are still possible, and have in fact been attempted (for example in the Lojban translation of Alice in Wonderland). Since Lojban will almost always be a second language, bilingual puns and word play abound, often based on the relative ambiguity of the other languages involved. Humor based on internal grammatical ambiguity is of course impossible in Lojban, but humor based on nonsensical statements, or on logical structures that would be difficult to clearly express in another language, becomes easier.
As speakers become fluent, and conventional phrases come into use, Lojban will develop its own forms of spoonerisms and subtle puns. Unique forms of Lojban word-play have already turned up; they exploit the way small variations in Lojban grammar create unexpected variations in meaning, and the capability to simply express rather mind-boggling relationships. Like all word-play, these lose zest when translated into other languages.
Related to humor is the aphorism: the pithy saying that gains pungency or poignancy from terse, elegant phrasing. Lojban seems as capable of aphorisms as any language, perhaps more than most; however, because the language is so young, few such aphorisms have been devised to date.
There have been hundreds of artificial international languages developed, of which Esperanto is the most successful and widely known. Esperanto, like most other such languages, was based on European languages in both grammar and vocabulary. Although it manages to be relatively neutral between them, it still retains an inherent cultural bias which makes it unsuited for most of the purposes that Lojban was designed for.
Lojban is culturally fully neutral. Its vocabulary was built algorithmically using today's six most widely spoken languages: Chinese, Hindi, English, Russian, Spanish, and Arabic. Lojban's words thus show roots in three major families of languages spoken by most of the world's people. Lojban's grammar accommodates structures found in non-European languages, and uses sounds found in many of the world's languages. Coupled with the potential computer applications that will make Lojban a useful language to know, Lojban's potential as an international language may be more far-reaching than Esperanto's.
Lojban was not designed primarily to be an international language, however, but rather as a linguistic tool for studying and understanding language. Its linguistic and computer applications make Lojban unique among proposed international languages: Lojban can be successful without immediately being accepted and adopted everywhere, and Lojban can be useful and interesting even to those skeptical of or hostile towards the international language movement.
Since Lojban is also not in direct competition with Esperanto, it has proven attractive to Esperantists interested in acquiring a new perspective on their own international language, and who feel less threatened because Lojban has different goals. Lojban's supporters recognize that it will take decades for Lojban to acquire both the number and variety of speakers and the extensive history of usage that marks Esperanto culture. Meanwhile, each language community has much to learn from the other; this process is already well underway.
English is commonly used as an 'international language' in the fields of science and technology, and is probably the most widely spoken language in the world. American dominance of technology in the twentieth century has caused massive borrowing from English into other languages that do not have words for all these new concepts. This dominance, and a heritage of colonialism and imperialism that has built resentment towards American and European impositions on native cultures, has caused recent movements in other countries away from English. The rising influence of other non–English-speaking countries on world economics, science, and technology makes further declines in the universality of English likely.
In addition, many who know English as a second language speak it only minimally, though they may be able to read or understand many words. India is a prominent example of a country where English is the only language more or less understood throughout the country, which has about 1500 languages and dialects; but the English spoken in India is often unintelligible to Americans or Britons. In fact, English is one of the most difficult languages to learn to use well. In countries where English is spoken along with other languages, it has been adapted into dialects which match the local culture and borrow words from the other local languages. Some of these dialects are as much as 70% unintelligible to American or British speakers, or to each other. As such, there is no single English language to call an 'international' one.
Lojban is a single language, with design features to discourage breaking up into separate languages. While it was developed primarily by Americans, and was designed to be at least as expressive as English is, Lojban's cultural neutrality gives equal priority to the structures and concepts of other languages and cultures. This cultural neutrality enhances Lojban's acceptability as an international language. Since it is as capable as English is of generating or borrowing any words needed to support the concepts of science and technology, and has special advantages for computer applications, Lojban is likely to spread worldwide through the technological community. Far more so than English, Lojban is simple and easy to learn for people of all cultures.
Original poetry has already been written in Lojban, and some has been translated into the language. Lojban's powerful tanru metaphor structure allows you to build concepts into words easily, as you need them, and has been used to create colorful images and to convey moving emotions. A Lojban speaker doesn't need a dictionary to use and understand millions of words that can potentially exist in the language. The absence of cultural constraints makes consideration of new ideas and relationships easier than in natural languages, spurring creativity. Lojban aids in communicating abstractions by identifying their nature explicitly. Lojban is thus a very powerful language, not only for poetry, but for discussing such abstract fields as philosophy, physics, metaphysics, and religion.
Lojban poets are already experimenting with new (and old) forms of poetry that seem especially well suited to the rhythm, sound, and flow of the language. Rarely do poets have such an opportunity to affect the development of a new language as they now can with Lojban. Lojban's rich and powerful. Lojban unleashes the full potential of poetic expression to communicate both concrete and abstract ideas.
The language, then called 'Loglan', was first described in the 1950s by Dr. James Cooke Brown. The 1960 Scientific American article Loglan was his call for assistance in developing the language. A revolution in linguistics was simultaneously taking place, resulting in a rapidly increasing knowledge of the nature of human language; this changed the requirements for the developing language. The first widely distributed Loglan dictionary and language description did not appear until 1975; the incompleteness of this description and continued development work discouraged people from learning the language. Furthermore, computers caught up with Loglan just then, making it possible to refine the grammar, eliminate ambiguity and mathematically prove its absence. For over forty years, this work has been performed by volunteers, and without financial support. Now, after several versions of the language, people have been learning and using the current version, which is the first to be called 'Lojban' (from the roots "logical-language" in Lojban).
This version is the first version with a stable vocabulary, and the first to have a stable and completely defined grammar. The stabilization of the language in this version has followed a painstaking and extensive period of research and analysis, between 1988 and 1998. Thus, in an important sense, Lojban is a very new language. To ensure Lojban remains stable while people learn it, the language definition is being closely controlled; the grammar and core vocabulary have already been baselined (frozen) for several years. When the number of speakers has grown significantly, and a Lojban literature has developed, Lojban will be treated like a natural language and allowed to grow and flourish without constraint, as do other natural languages.
Questions of how many people speak a language greatly depend on your presuppositions and definitions — which a language like Lojban, at least, can make explicit! The on-line Lojban mailing list, which constitutes the largest community of people using the language, has over 200 subscribers, with well over 20 regular posters as of this writing. The level of confidence of the language community has already risen to such a level that there is a Lojban-language–only discussion group, as well as the general mailing list. Lojban has also been used extensively in real-time conversation, both electronically (IRC) and face-to-face. Though the Lojban-speaking community is so widely diffused that the opportunity for conversation does not arise frequently, the number of Lojbanists who can sustain a conversation in the language certainly ranges beyond what can be counted on the fingers of one hand, and is steadily increasing. Lojban has been proven in communicative use for well over a decade, and the range and expressivity of the language is being continually explored by the language community.
The first speakers of Lojban have a unique opportunity. They are the history-makers who will shape the flavor of the first totally new language to achieve broad speakability. Their ideas will be most influential in setting the patterns of usage that others will learn from. Their experiences will teach things about language that have never before been learned — or learnable.
There are several reasons for learning the language now. Those who are working with the language now are actively consulted for their opinions on how to teach and spread the language. Within a few weeks of work learning from the materials already written, you will be able to work with those who have already started. You will be a significant part of this small but rapidly growing community. You will receive personal attention to any problems you have with the language from those leading the effort. If you are truly ambitious and committed to the language, you are welcome to join in that leadership.
Those with a computer background who learn the language now will be the leaders in developing the earliest practical computer applications for the language. Meanwhile, computer-oriented Lojbanists can also aid in developing computer-aided instruction tools or converting existing software to run on new computers.
People not interested in computers will also find Lojban a valuable language. You may be interested in the Sapir–Whorf hypothesis, and in the scientific tests to be planned and conducted, or in other language-related research. You may be interested in Lojban's potential as an international language, and in the attempts to use the language to reach across cultural boundaries.
Regardless of your background, you will find learning Lojban to be a mind-expanding experience. Learning any language other than your native tongue broadens your perspectives and allows you to transcend the necessarily limited viewpoints of your native language's culture. Lojban, being simpler to learn than natural languages, provides this benefit much more quickly than does the study of other languages. And being quite different from natural languages, Lojban provides this benefit more directly.
Having learned Lojban, you will find it easier to learn other languages and to communicate with people from other backgrounds, regardless of the language studied; the linguistic principles you learn while learning Lojban are applicable to these languages and the communication problems they entail. The logical organization embedded in Lojban will aid you in organizing and clarifying your thoughts. Your new perspective on language, ambiguity, and communication will allow you to express those thoughts more clearly, even when you use an ambiguous natural language.
You needn't learn Lojban for any practical purpose, however. Many, if not most, of those who are learning Lojban are doing so because it is fun. Learning Lojban is intellectually stimulating, providing human interaction (a way to meet other people and get to know them) and mental challenge. Lojban has all the benefits of games designed for entertainment, with the side benefit of that entertainment developing into a useful skill.
Learning Lojban as an intellectual toy means that you can get enjoyment from learning Lojban without anywhere near the effort needed to benefit from studying other languages. While becoming fluent in Lojban will probably take hundreds of hours over several months, you can feel some sense of accomplishment in the language after just a couple of hours of study. You can use Lojban immediately for fun, while gaining skill with greater experience.
This text appears in a booklet including a description of the grammar of Lojban and some introductory learning materials. If you are reading this text in a separately printed brochure, you may write to the Logical Language Group at the address found at the end of this brochure, and we will be happy to provide the complete booklet. We request a contribution of $5 to cover its cost.
If you are reading this brochure on-line, or have access to the Internet, the complete What is Lojban? booklet is also available on the World Wide Web for free at the address:
Once you have read this booklet, there are several directions you may proceed, depending on your goals for use of the language.
Most people learning the language will work for some time on their own before working with others. We recommend, where possible, that you identify at least one other person to study and interact with, either in person or by mail. The Logical Language Group maintains lists of Lojban students of various degrees of skill and activity levels. There is also both a general and an in-Lojban discussion group available on the Internet. Information will be found at the end of this document.
Almost any use you wish to make of Lojban requires some degree of mastery of the basic vocabulary. You can learn enough Lojban grammar to support conversation in just a couple of hours, but you will need vocabulary in order to use that grammar.
You can learn the Lojban vocabulary using computer software. The Logical Language Group has computer-aided–teaching programs distributed under the name LogFlash, with MS-DOS/Windows, Macintosh and Unix versions currently available. The software is based on flash-card teaching techniques, which are extremely efficient in helping you learn the vocabulary. Other computer software is available, including a parser and a glosser.
You can learn the Lojban grammar in several ways, including by studying the examples in our on-line text archives and mailing lists, and by going through the formal grammar description. (The formal grammars are available in two formats, YACC and simplified E-BNF.)
An introduction to the grammar of Lojban will be found in Technical Descriptions in the What is Lojban? booklet. There is also a set of introductory lessons available (these cover the basics of the language, but at a more leisurely pace): Lojban for Beginners, by Robin Turner and Nick Nicholas. A complete grammatical description of Lojban, The Complete Lojban Language by John W. Cowan, was published by the Logical Language Group in 1997. This is an authoritative reference, and can be used as an aid to learning the advanced features of the language.
A formal Lojban dictionary is being compiled, and will encompass the word lists already available from the Logical Language Group as of this writing. Draft versions of the dictionary are available on the Lojban web site (see contact details below).
Of course the only way to really learn a language is to use it. The Logical Language Group will assist you in finding other Lojban students of comparable skill level and interests, either in your local area or reachable by post or electronic mail. The on-line Lojban discussion groups regularly contain Lojban text, some with detailed translations and some without translation, as well as discussions of language points by various members of the Lojban community. There is also a discussion group specifically for beginners as of this writing. Of course the best way to use the language is to recruit friends and associates into studying and using the language with you. Even if they are not interested in the same language goals as you are, the 'hobbyist' aspect of the language will provide interesting and stimulating entertainment for all concerned.
The Logical Language Group, Inc. is a non-profit organization, the embodiment of the Loglan/Lojban community. We were founded to complete the language development process, to develop and publish teaching materials, to organize and teach the community, to promote applications of Lojban, and to initiate and lead research efforts in linguistics, language education, and other areas related to Lojban. Simply put, our purpose is to serve you in all manner of things Lojbanic. The Logical Language Group is not affiliated with The Loglan Institute, Inc., the organization founded by James Cooke Brown.
The Logical Language Group is also called la lojbangirz. (/lah lozh-BAHN-geerz./), its Lojban name. It was founded informally in 1987, and incorporated in 1988. The U.S. Internal Revenue Service approved our status as a non-profit educational/scientific charity in 1989, making donations and grants to the organization deductible under U.S. tax law.
Loglan/Lojban has been developed almost totally by volunteer labor and small donations of money. Lojban attracts people who are willing to devote a lot of time and effort to seeing their dreams become reality. Thus, our only income has been money derived from sales of our publications, and donations from interested supporters.
The Logical Language Group publishes and sells printed materials on Lojban. All language definition information is considered in the public domain, and most Logical Language Group publications are distributed under a policy which allows not-for-charge copying and redistribution. Computer versions of many of our publications are available on-line at no charge. We ask people who receive our materials by any of these means to let us know, so that we may better serve you, and donate liberally, so that we may continue to serve you.
Most materials that we sell require either prior payment, an informal commitment to pay on your part, or your statement that you cannot afford to pay for materials (in which case our supplying these materials is at our discretion). We attempt to flexibly support Lojbanists who have financial constraints, and will accept reasonable offers of reduced or delayed payments subject to our financial condition, given your commitment to actively maintain contact and involvement with the community. Obviously, the level of your prior and current activity and any commitments you make to learning the language, or to volunteer work for la lojbangirz., will be factored into our decision.
la lojbangirz. has a special commitment to support Lojbanists outside the U.S., because so many of the language goals are dependent on building an international community of speakers, and because we recognize the difficulties caused by the international currency market and the relative wealth of nations. We can accept bank cheques in most currencies and international payment via PayPal. We also encourage people to form groups so that they can receive a single copy of our materials, copying or passing them to others to keep the per-person costs low. We expect a lower standard of contact and contribution from overseas Lojbanists when deciding whether to continue sending our materials at reduced or no charge.
We ask all recipients of our materials to help us financially in any way you can. The Logical Language Group needs your gifts for support of the Loglan/Lojban project. Artificial languages are historically not self-sustaining financially, and have difficulty receiving outside support. The Logical Language Group, Inc. is prohibited by its bylaws from spending more than 15% of its expenses for administrative purposes, except by special agreement with a donor who agrees to cover such added costs in full.
The Logical Language Group coordinates and promotes activities involving Lojban and the Lojban community. In that role, it publishes materials enabling people to learn the language, and facilitates their forming a community of speakers. Most people involved with Lojban stay informed by checking our web page or participating in the Lojban mailing lists (see contact details below). The Logical Language Group also publishes newsletters and journals, including both general news, aimed at those not actively involved in learning and using the language, and more specific material, including discussions of features of the language, debates on research issues and applications, letters from the community and responses, and Lojban writings and translations.
Our printed publications are free of advertisements (other than our own ordering information, and occasional mention of individuals and organizations who have contributed particular service to our efforts); and we do not sell our mailing list. Our publications are distributed as cheaply as possible to encourage new people to participate. In the interest of attracting the widest audience possible, we are committed to distributing as much material as possible using the 'open source' concept for computer software and a similar policy for printed publications. This policy retains our copyrights but allows you, with relatively few restrictions, to copy our materials for your friends.
Certain materials that we publish contain information that we place in the public domain. All language definition information is considered to be public.
If you are attempting to learn the language, we will provide as much help as we can to assist you. We will put you in touch with Lojbanists who might be interested in studying or communicating with you in the language. You can also send your writings to us for review, or for indirect exchange with others. We try to foster research and social interaction among those who are learning, or who have already learned the language. We aid such people in organizing, leading, and teaching formal classes and study groups, and will sponsor affiliated groups in local areas where non-profit sponsorship can be of benefit. We conduct an annual celebration of the language and community (July or August), called 'Logfest', in conjunction with our annual business meeting in the Washington DC area. We also expect to support other local meetings and gatherings as the community grows.
Of course, we also try to publicize the language. Our representatives can attend meetings to give presentations on the language. We distribute informational material, including these booklets. Through our efforts, and with your help, the community of Lojbanists is rapidly growing.
You can become involved in the Lojban project in a variety of ways, depending on your background and interests, and on your available time:
you can participate in completing the language documentation;
you can devise applications for Lojban in computers, education, linguistics, and other fields;
you can help in organizing Lojbanists in your area, and in recruiting new Lojbanists;
you can help in teaching the language to new people (even while learning yourself);
you can assist in spreading Lojban to non–English-speaking cultures by helping translate materials into other languages, and by identifying, recruiting, and communicating with contacts in other countries (international involvement is vital to ensuring that Lojban remains culturally neutral);
you can contribute financially to support our organization, its activities, and its publications;
you can use Lojban in composition, translation, and conversation with other Lojbanists.
For many of these activities, you need to learn the language first. However, even those who haven't yet had time to learn the language can assist in recruiting and contributing ideas to the effort.
Helping to publicize the language, of course, does not take a lot of time, or necessarily even knowing the language. Talk to friends, relatives and colleagues. We will gladly provide copies of this brochure on request. Lojban tends to sell itself; people who learn of it are more often than not intrigued by it.
Keep in touch with us. We want to know your ideas and opinions on the language, on our various activities, and on our products. We welcome open debate on the language, and have even printed and made available writings that are critical of various aspects of our efforts, when they are of sufficient general interest. Open debate aids in understanding and improves the overall quality of the language and of our presentation of it to the world. Much of the language design is now complete, and the Logical Language Group is committed to maintaining a stable version of the language. Nonetheless, we would rather hear criticism now within our community and either correct our problems or prepare an adequate response, than do so later when such issues are raised by outsiders.
In short, Lojban is a product of all of the community, including you — if you choose.
Of course, the most important thing you can do is:
Use Lojban!: Lojban will not really achieve the status of 'language' until people use it. We need creative people to write Lojban prose, poetry, and dialog. We need translations made from fiction, technical literature, from religious and philosophical writings, and from music. Only in this way will Lojban be proven practical, and gain the credibility it needs to succeed.
We have several volunteers who serve to coordinate Lojban activities in specific regions of the world. There is also a limited amount of Lojban materials translated into languages other than English. This support is constantly being added to; please contact us for details.
The Logical Language Group's website, which contains all its publicly available information, is at:
Several active Lojban-related mailing lists are available on the Internet. The general Lojban list is lojban; the list for discussions in Lojban only is jbosnu; and the list specifically for beginners is lojban-beginners. They may be accessed as follows:
| Web |
|
|
|
|
||
| Subscribe |
http://www.lojban.org/lsg2/ for all lists. |
(All lists are mirrored outside yahoo.com, on the Lojban web server: http://www.lojban.org/lsg2/)
If you have received a registration form and an order form with this booklet, you can provide us with useful information to aid us in serving you, and can order some of our materials. Write or call:
E-mail can be sent to us at: [email protected]The Logical Language Group, Inc.
2904 Beau Lane
Fairfax, VA 22031
U.S.A.
(+1 703) 385-0273
.e'osai ko sarji la lojban.
/eh-ho-sigh, ko-SAHR-zhee, lah LOZH-bahn./
Please support Lojban!
This overview of Lojban will hopefully give you a good feel for the design and scope of the language. It serves as an introduction to learning the language; most of the special terminology used elsewhere is defined here. This overview is not complete, nor detailed; much is glossed over. To actually learn the language you must study the available reference or teaching materials.
The material following is divided up into the major facets of language description. These are:
the way the language is written
the way the language sounds
the structure of words
the meanings of words, sentences, and expressions
the ways in which words may be put together
For many special terms, we will give a definition, and then the Lojban word for the concept. The Lojban words are then used, to avoid confusion due to the various meanings of the English jargon words. The Lojban words are also what is used in other publications about the language.
Lojban uses the Roman alphabet, consisting of the following letters and symbols:
omitting the letters h, q, and w. The three special characters are not punctuation:' , . a b c d e f g i j k l m n o p r s t u v x y z
The apostrophe represents a specific sound, similar to the English /h/.
The period is an optional reminder to the reader, representing a mandatory pause dictated by the rules of the language. Such pauses can be of any duration, and are part of the morphology, or word formation rules, and not the grammar.
The comma is used to indicate a syllable break within a word, generally one that is not obvious to the reader.
Lojban does not require capitalization of any word type, including proper names, and such capitalization is discouraged. Capital letters are used instead to indicate non-standard stress in pronunciation of Lojbanized names. Thus the English name Josephine, as normally pronounced, is Lojbanized as DJOsefin, pronounced /JO,seh,feen/. Without the capitalization, Lojban stress rules would force the /seh/ syllable to be stressed.
Lojban's alphabet and pronunciation rules bring about what is called audio-visual isomorphism. There is not only a unique symbol to represent each sound of Lojban, but also a single correct way to separate the sounds of continuous Lojban speech into words. Similarly, a Lojban text may be read off sound by sound, using pronunciation and stress rules, to form an unambiguous uttered expression. Spelling in Lojban is thus trivial to learn.
Each Lojban sound is uniquely assigned to a single letter, or combination of letters. Each letter is defined to have a particular set of possible pronunciations, such that there is no overlap between letter sounds.
Most of the consonants are pronounced exactly as they are most commonly pronounced in English. The following gives English and Lojban examples for these.
Note: In the following examples, the English word and the Lojban word are the same where possible. (This was not possible for j.)
Unvoiced.
Voiced.
Incidentally, for these examples, the Lojban example is a close equivalent of the English example used, showing that some words in Lojban are very similar to their English counterparts. In the pronunciation guides, note the conventions of capitalizing stressed syllables and of separating syllables with commas. These conventions could optionally be used in the Lojban words themselves, but are not necessary.
In the above examples, the consonants in the first table are called unvoiced consonants, because they are spoken without voicing them using the vocal folds. The consonants in the second table are their voiced equivalents.
When a consonant is made by touching the tongue so as to block air passage, it is called a stop (p, b, t, d, k, g). If the blockage is incomplete, and air rubs between the tongue and the roof of the mouth, it is called a fricative (f, v, s, z). For example, k is an unvoiced stop in the back of the mouth. Its unvoiced fricative equivalent is x, which is rarely found in English (the Scottish loch, as in Loch Ness monster, is an example).
Two other fricatives are c and j. c is the unvoiced /sh/ sound that is usually represented by two letters in English. j is its voiced equivalent, rarely occurring alone in English (but see below).
These two fricatives occur frequently in English combined with a stop (giving affricates). Lojban phonology recognizes this, and the /ch/ sound is written tc, while the /j/ sound is written dj.
The other four Lojban consonants are also pronounced as in English. But each has two possible pronunciations. The normal Lojban pronunciation is shown in the first table. In names, borrowings, and a few other situations, however, these consonants can occur in a syllable of their own, with no vowel. In this case they are called syllabic consonants, and are pronounced as in the second table.
Non-syllabic.
Syllabic.
Note: The names given above have syllabic consonants in American English. In British English, Burt is pronounced instead as byt, Carl as kal, Ellen usually as .elyn or .elen, and Miriam as miri,ym.
Consonants may be found in pairs, or even in triples, in many Lojban words; even longer clusters of consonants, often including at least one syllabic consonant, may be found in Lojbanized names or borrowings. Some of these clusters may appear strange to the English speaker (for example mlatu /MLAH,tu/), but all permitted clusters were chosen so as to be quite pronounceable by most speakers and understandable to most listeners. If you run across a cluster that you simply cannot pronounce because of its unfamiliarity, it is permissible to insert a very short non-Lojban vowel sound between them. The English /i/ as in bit is recommended for English speakers.
The basic Lojban vowels are best described as being similar to the vowels of Spanish and Italian. These languages use pure vowels, whereas English commonly uses vowels that are complexes of two or more pure vowels called diphthongs (2-sounds) or triphthongs (3-sounds). English speakers must work at keeping the sounds pure; a crisp, clipped speech tends to help, along with keeping the lips and tongue tensed (for example by smiling tightly) while speaking.
There are five common vowels (a, e, i, o, u), and one special-purpose vowel (y). English words that are close in pronunciation are given, but few speakers pronounce these words in English with the purity and tension needed in Lojban pronunciation.
| a | /ah/ | father, (American) top | patfu | /PAHT,foo/ |
| e | /eh/ | bet, lens | lenjo | /LENN,zho/ |
| i | /ee/ | green, machine | minji | /MEEN,zhee/ |
| o | /o/ | joke, note | notci | /NO,chee/ |
| u | /u/ | boot, shoe | cutci | /SHOE,chee/ |
| y | /uh/ | sofa, above | lobypli | /LOBE,uh,plee/ |
The sound represented by y, called 'schwa', is a totally relaxed sound, contrasting with all the other tensed vowels. In this way, the Lojban vowels are maximally separated among possible vowel sounds. The English speaker must be especially careful to ensure that a final unstressed vowel a in a Lojban word is kept tensed, and not relaxed as in the English sofa (compare the equivalent Lojban sfofa /SFO,fah/, not sfofy /SFO,fuh/).
Lojban has diphthongs as well, but these are always represented by the two vowels that combine to form them:
Rising diphthongs.
Falling diphthongs.
The diphthongs in the second table are found in Lojban only when used as words by themselves, and in Lojbanized names. Those in the first table may be found anywhere.
Any other time these vowel pairs occur together in a single word, they must be kept separate in order to unambiguously distinguish the separate vowels from the diphthongs. The principle has been extended to all Lojban vowels for consistency, and all non-diphthong vowel pairs in a word are separated in print and in sound by an apostrophe ('), representing a short, breathy /h/ sound. (Say Oh hello quickly and without a pause between the words to get an English equivalent, in this case of Lojban o'e. Any voiceless non-Lojban sound may also be used.)
When the vowels occur together, one at the end of a word and the other at the beginning of the next word, the ' is not used to separate them. (Were it used, it would join them into a single word). Instead, a pause is mandatory between the two vowels. The pause may be extremely short (called a glottal stop) as in the English he eats, or may be longer. The pause is mandatory and thus may be inferred without writing it, but it is usually signalled to a reader with a period (.) before the word starting with a vowel.
A pause is also required after any Lojban name, which always ends in a consonant. (A "." is written after the name to mark this, thus distinguishing names from other words without using capitalization.) Every vowel-initial Lojban word is thus preceded by a pause, and such words are usually spelled with a "." at the beginning. There are a small number of other places where pauses are required to separate words. "." may be used to mark the separation in these cases as well.
Lojban words of more than one syllable are stressed on the next-to-last, or penultimate, syllable. (The apostrophe counts as a syllable break: blari'o is stressed as blaRI'o.) Syllables for which the vowel is y are not counted in determining penultimate stress, nor are syllables counted in which the letters l, m, n, or r occur in their syllabic forms, with no other vowel in the same syllable. (Thus, lobypli = LO,by,pli, .uacintn. = .UA,cin,tn., kat,rin. = KAT,r,in.) In Lojbanized names, a speaker may retain a semblance of native pronunciation of the name by stressing a non-penultimate syllable. In this case, capitalization is used to mark the abnormal stress, as in DJOsefin. 'Josephine' in the example above.
It is not mandatory to mark stress and pause in writing in Lojban, except for word separation according to the rules above. There is no mandatory intonation, like the rising tone that always accompanies an English question. Lojban equivalents of English intonations are expressed as spoken (and written) words, and may be adequately communicated even in a monotone voice. Such intonation, and pauses for phrasing, are then totally at the speaker's discretion for ease in speaking or being understood, and carry no meaning of their own.
The forms of Lojban words are extremely regular. This, coupled with the phonology rules, allows a stream of speech to be uniquely broken down into its component words.
Lojban uses three kinds of words:
| cmene |
names |
|
| brivla |
'predicate' words |
|
| cmavo |
'structure' words |
Names, or cmene, are very much like their counterparts in other languages. They are labels applied to things or people, to stand for them in descriptions or in direct address. They may convey meaning in themselves, describing concretely what they are refering to, but do not necessarily do so. Because names are often highly personal and individual, Lojban attempts to allow native language names to be used with a minimum of modification. However, most names must be Lojbanized to some extent, to prevent potential ambiguities. Examples of Lojbanized cmene include:
| djim. |
Jim |
|
| djein. |
Jane |
|
| .arnold. |
Arnold |
|
| pit. |
Pete |
|
| katrinas. |
Katrina |
|
| katr,in. |
Catherine |
|
| katis. |
Cathy |
|
| keit. |
Kate |
cmene may have almost any form, but always end in a consonant, and are followed by a pause. cmene are penultimately stressed, unless unusual stress is marked with capitalization. A cmene may have multiple parts, each ending with a consonant and pause, or the parts may be combined into a single word with no pause. Thus djan. djonz. /jahn.jonz./ and djandjonz. /JAHNjonz./ are valid (American) Lojbanizations of John Jones, while .iunaited. steits. and either .iuNAItet,steits. or .iunaitet,STEITS. are valid Lojbanizations for United States, depending on how you wish to stress the name. In the last example, writing the cmene as a single word requires capitalization of the stressed syllables /NAI/ or /STEITS/, neither of which is penultimate in the single-word form of the cmene.
Note: Lojban words do not allow a voiced consonant (like d) to be next to an unvoiced consonant (like s), without an intervening pause. This is why the single-word version of United States goes into Lojban as .iunaitet,steits., whereas the two-word version remains as is: .iunaited.steits.
The final arbiter of the correct form of the cmene is the person doing the naming — although most cultures grant people the right to determine how they want their own name to be spelled and pronounced. The English Mary can thus be Lojbanized as meris., maris., meiris., or even marys. The latter is not pronounced much like its English equivalent, but may be desirable to someone who values spelling over pronunciation consistency. The final letter need not be an s; it must, however, be a Lojban consonant of some variety.
cmene are not permitted to have the words la, lai, or doi embedded in them, because they are always preceded by one of these words or by a pause. With one of these words embedded, the cmene might break up into valid Lojban words followed by a shorter, incorrect cmene. There are similar alternatives to these that can be used in Lojbanization, such as ly, lei, and do'i, that do not cause these problems.
'Predicate' words, or brivla, are the core of Lojban. The concept of 'predicate', or bridi, will be discussed in the grammar section below. brivla carry most of the semantic information in the language. They serve as the equivalent of English nouns, verbs, adjectives, and adverbs, but are treated identically in Lojban grammar.
brivla may be recognized by several properties:
they have more than one syllable
they have a consonant cluster (at least two adjacent consonants) within or between the first and second syllables
they end in a vowel
The consonant cluster rule has the qualification that the letter y is totally ignored, even if it splits a consonant cluster. Thus lobypei /LOBE,uh,pay/ is a brivla even though the y separates the bp cluster.
brivla are divided into three subcategories according to how they are created:
brivla are defined so as to have only one meaning, which is expressed through a unique place structure. This concept is discussed further in the sections on semantics and grammar.
The gismu are the basic roots for the Lojban language. These roots were selected based on various criteria:
occurrence or word frequency in other languages
usefulness in building complex concepts
and a few, like the words gismu, cmavo, and lujvo, are included as uniquely Lojbanic concepts that are basic to the language.
Each gismu is exactly five letters long, and has one of two consonant-vowel patterns: CVCCV or CCVCV (e.g. rafsi, bridi). The gismu are built so as to minimize listening errors in a noisy environment.
When specifying a concept that is not found among the gismu, a Lojbanist generally attempts to express the concept as a tanru. tanru is an elaboration of the concept of 'metaphor' used in English. In Lojban, any brivla can be used to modify another brivla. The first of the pair modifies the second. Modifier brivla may thus be regarded as acting like English adverbs or adjectives. For example, skami pilno is the tanru which expresses the concept of 'computer user'.
When a concept expressed in a tanru proves useful, or is frequently expressed, it is desirable to choose one of the possible meanings of the tanru and assign it to a new, single brivla. In the example, we would probably choose the meaning 'user of computers', and form the single brivla sampli, out of the tanru skami pilno. Such a brivla, built from two or more component gismu, is called a lujvo.
Like gismu, however, lujvo have only one meaning. Unlike gismu, lujvo may have more than one form. This is because each gismu has between two and five combining forms called rafsi, which are joined together in order to form a lujvo (e.g. sam and skam for skami; pli and piln for pilno). Longer rafsi may be used in place of shorter rafsi; the result is considered the same lujvo, even though the word is spelled and pronounced differently. Thus brivla, itself a lujvo built from the tanru bridi valsi, is the same lujvo as brivalsi, bridyvla, and bridyvalsi — each using a different combination of rafsi.
The use of tanru or lujvo is not always appropriate for very concrete or specific terms (e.g. brie or cobra), or for jargon words specialized to a narrow field (e.g. quark, integral, or iambic pentameter). These words are in effect 'names' for concepts, and the names were invented by speakers of another language. The vast majority of names for plants, animals, foods, and scientific terminology cannot be easily expressed as tanru. They thus must be 'borrowed' (actually 'copied') into Lojban from the original language, forming words called fu'ivla.
A borrowed word must be Lojbanized into one of several permitted fu'ivla forms. A rafsi is then attached to the beginning of the Lojbanized form, usually using a syllabic consonant as 'glue' to ensure that the resulting word is not construed as two separate words. The rafsi categorizes or limits the meaning of the fu'ivla; otherwise a word having several different jargon meanings in other languages (such as integral) would be unclear as to which meaning should be assigned to the fu'ivla. fu'ivla, like other brivla, are not permitted to have more than one definition.
cmavo are the structure words that hold the Lojban language together. They often have no concrete meaning in themselves, though they may affect the semantics of brivla to which they are attached. cmavo include the equivalent of English articles, conjunctions, prepositions, numbers, and punctuation marks.
cmavo are recognized most easily by not being either cmene or brivla. Thus, they:
may be a single syllable
never contain a consonant cluster of any type, whether or not y is counted
end in a vowel
need not be penultimately stressed, though they often are if they have more than one syllable
All cmavo display one of the following letter patterns, where C stands for a consonant, and V stands for a vowel:
| V | VV | V'V | CV | CVV | CV'V |
The letter pattern generally does not indicate anything about the grammar of the cmavo.
A sequence of cmavo can be written without intervening spaces, without any change to its meaning. Such a sequence is called a compound cmavo. For example, a set of digits comprising a longer number can be written as a single word (e.g. pareci = pa + re + ci = '123').
Note: As far as the stress rules of Lojban are concerned, however, these are still separate words. So you don't have to stress pareci as paREci.
A small number of cmavo used in tanru have been assigned rafsi, so that they may aid in converting those tanru into lujvo.
Lojban is designed to be unambiguous in orthography, phonology, morphology, and grammar. Lojban semantics, however, must support the same breadth of human thought as natural languages. Every human being has different 'meanings' attached to the words they use, based on their unique personal experiences with the concepts involved. So it is impossible to eliminate semantic ambiguity (the ambiguity embedded in the variable meanings of words when taken in context) completely.
Rather, Lojban attempts to minimize semantic ambiguity, partly by systematizing as much as possible about semantics, but mostly by removing the clutter and confusion caused by other forms of ambiguity.
Unlike words in most other languages, a brivla has a single meaning, which however may encompass a narrow or broad range of closely related submeanings. gismu tend to have more general meanings, while lujvo tend to have specific definitions; the compounding of gismu into lujvo allows expression of any desired degree of specificity. fu'ivla have a single narrow meaning.
The semantic definitions of brivla are closely tied to the 'predicate' nature of brivla, a topic discussed in detail in the grammar section below. In short, a brivla defines the relationship between a group of separate but related concepts, called its sumti.
brivla are not nouns, verbs, adjectives, or adverbs; yet they incorporate elements of each. These different aspects are brought out in the way the brivla is used in the grammar, but the different grammatical environments do not change the meaning of the brivla.
brivla are an open-ended set of words; new lujvo and fu'ivla may be created as needed. Eventually, invented brivla will be collected and analyzed, and added to a formal dictionary. The definitions of all gismu, including their place structures, have already been specified. The place structure of a lujvo can generally be inferred from the place structures of its component gismu, using conventions which are generally useful though not hard-and-fast. fu'ivla are generally concrete terms, with simple and fairly obvious place structures. When there is uncertainty, listeners can ask about unknown or confusing place structures.
The heart of Lojban semantics is embedded in tanru. The meaning of a tanru is somewhat ambiguous: for instance, skami pilno could refer to a computer that is a user, or to a user of computers. There are a variety of ways that the modifier component can be related to the modified component. cmavo are used within tanru to prevent grammatical ambiguities, such as the various possible groupings of words in a phrase like pretty little girls school ({pretty {little {girls school}}}, {{pretty little} {girls school}}, {{pretty {little girls}} school}, and so on).
A speaker may use tanru to be arbitrarily general or specific. tanru are usually meant to be quite straightforward; tanru are always considered as a series of pairs of terms, a binary metaphor relationship. In such a relationship the first term by default modifies the second term. The terms may be brivla, certain cmavo such as numbers, or shorter tanru.
The connotative semantics of Lojban sentences — that is to say, the meaning contained not in the words themselves, but in the associations people make with them — is still relatively undefined. The same is true for the semantics of longer expressions or texts. There is as yet nothing clearly corresponding in Lojban to 'mood' or 'tone', no 'formal' or 'informal' styles, etc.
Because the language is oriented towards logic, the nature of the assertion in a statement, and whether it is true or false, are especially significant. Certain constructs in the language are described as making assertions, and having truth values (that is, being true or being false). Other constructs may modify those truth values, and still other constructs are interpreted independently from the truth of the statement.
Lojban's grammar is defined by a set of rules that have been tested to be unambiguous using computers. Grammatical unambiguity means that in a grammatical expression, each word has exactly one grammatical interpretation, and that within the expression the words relate grammatically to each other in exactly one way. (By comparison, in the English Time flies like an arrow, each of the first three words has at least two grammatical meanings, and each possible combination results in a different grammatical structure for the sentence.)
The machine grammar is the set of computer-tested rules that describes, and is the standard for, 'correct Lojban'. If a Lojban speaker follows those rules exactly, the expression will be grammatically unambiguous. If the rules are not followed, ambiguity may exist. Ambiguity does not make communication impossible, of course. Every speaker on Earth speaks an ambiguous language. But Lojbanists strive for accuracy in Lojban grammatical usage, and thereby for grammatically unambiguous communication. (Semantic ambiguity, as we have seen, is another matter.)
It is important to note that new Lojbanists will not be able to speak 'perfectly' when first learning Lojban. In fact, you may never speak perfectly in 'natural' Lojban conversation, even though you achieve fluency in the language. No English speaker always speaks textbook English in natural conversation; Lojban speakers will also make grammatical errors when talking quickly. Lojbanists will, however, be able to speak or write unambiguously if they are careful, which is difficult if not impossible with a natural language.
In Lojban grammar rules, words are assembled into short phrases representing a possible piece of a Lojban expression. These phrases are then assembled into longer phrases, and so forth, until all possible pieces have been incorporated through rules that describe all possible expressions in the language. Lojban's rules include grammar for 'incomplete' sentences, for multiple sentences flowing together in a narrative, for quotation, and for mathematical expressions.
The grammar is very simple, but infinitely powerful; often, a more complex phrase can be placed inside a simple structure, which in turn can be used in another instance of the complex phrase structure.
The machine grammar includes rules which describe how each word is interpreted. A classification scheme categorizes each word based on what rules it is used in and how it interacts with other words in the grammar. All cmene are treated identically by the grammar, as are all brivla. The classification divides the cmavo of Lojban into about a hundred of these categories of grammar units, called selma'o. Whereas the three word types, namely cmene, brivla, and cmavo, are generally considered to correspond to the 'parts of speech' of English, these hundred-odd selma'o correspond to the more subtle variations in English grammar, such as the different kinds of pronouns, or the different ways of expressing the past tense of a verb. In this sense, English has hundreds of 'parts of speech'.
Lojban selma'o are named after one word within the category, often the one most frequently used. CU, KOhA, PU, and UI are examples of selma'o.
Note: The selma'o names are capitalized in English discussion of Lojban. The apostrophe is converted to h in such usage; this is for compatibility with computer grammar parsers.
The bridi is the basic building block of a Lojban sentence. bridi are not words, but concepts. A bridi expresses a relationship between several 'arguments', called sumti. Those with a background in algebra may recognize the word 'argument' in connection with 'functions', and a bridi can be considered a logical 'function' (called a predicate) with several 'arguments'. A brivla (bridi valsi = bridi-word) is a single word which expresses the relationship of a bridi.
The definition of a brivla includes a specific set of 'places' for sumti to be inserted, expressed in a certain order (called a place structure) to allow a speaker to clearly indicate which place is which. By convention, we number these places as: x1, x2, x3, x4, x5, etc., numbering from the left. Other letters may be used when referring to two or more place structures together.
The unique definition of a brivla is thus an enumeration of the component places in order, joined with a description of the relationship between them. The definition of the gismu klama 'come, go' can be expressed compactly as:
or in full detail:x1 comes/goes to x2 from x3 via x4 using x5
x1 describes a party that acts with result of being in motion;
x2 describes a destination where x1 is located after the action;
x3 describes an origin where x1 is located before the action;
x4 describes a route, or points along a route travelled by x1 between x2 and x3;
x5 describes the means of transport by which the result is obtained.
Note: The difference between the English verbs come and go depends on the relationship between x2 (the destination), x1 (the origin), and the speaker. The position of the speaker is not part of the Lojban meaning.
When actually using a brivla within a bridi, it is possible to fill the places (five in the case of klama) with five specific sumti. Consider the following example:
The definition of the brivla used above, klama, shows this relationship. There are five places labelled x1 through x5. The brivla itself describes how the five places are related, but does not include values for those places. In this example, those places are filled in with five specific sumti values:Example 1.
le prenu cu klama le zdani le briju le zarci le karce
The person comes/goes to the house from the office via the market using the car.
x1 contains le prenu (the person)
x2 contains le zdani (the house)
x3 contains le briju (the office)
x4 contains le zarci (the market)
x5 contains le karce (the car)
The brivla and its associated sumti, used in a sentence, have become a bridi. For logicians, the comparable English concept is called a predication. In each bridi, a brivla or tanru specifies the relationship between the sumti. Such a specification of the relationship, without the sumti expressed, is called a selbri (predicate in English). Whether or not any sumti are attached, a selbri is found within every bridi.
We express a bridi relationship in Lojban by filling in the sumti places, so that the position of the sumti in the place structure is clear, and by expressing the selbri that ties the sumti together.
It is not necessary to fill in all of the sumti to make the sentence meaningful. In English we can say I go, without saying where we are going. To say mi klama ("I go...") specifies only one sumti; the other four are left unspecified.
In Lojban, we know those four places exist; they are part of the definition of klama. In English, there is no implication that anything is missing, and the sentence I go is considered complete. As a bridi, mi klama is inherently an incomplete sentence. The omission of defined places in a bridi is called ellipsis; corresponding ellipsis in the natural languages is a major source of semantic ambiguity. Most Lojban expressions involve some amount of ellipsis. The listener, however, knowing that the omissions have occurred, has a means of asking directly about any specific one of them (or all of them), and resolving the ambiguity. So this kind of semantic ambiguity is not eliminated in Lojban, but it is made more recognizable and more amenable to resolution.
It is permissible to use a selbri alone, with no sumti filled in, as a very elliptical sentence called an observative. The sentence fagri is very similar to the English exclamation Fire!, but without the emotional content: it merely states that "something is a fire using some fuel", without explicitly specifying the identity of either.
You may have noticed that in example (1), each of the sumti filling the five places of klama contain a brivla. Each of these brivla are selbri as well; i.e. they imply a relationship between certain (usually unspecified) sumti places. A selbri may be labelled with le (among other things) and placed in a sumti. When le is used, the concept which the speaker has in mind for the x1 place of the selbri within the sumti is understood to fill that sumti place. For example, the sumti place for le prenu is filled with what the speaker has in mind as being the x1 place of prenu. Since prenu has the place structure "x1 is a person", le prenu thus corresponds to 'the person'.
In example (1), there are no places specified for any of the selbri embedded in the sumti; they are all elliptically omitted, except for the x1 place, which describes the sumti itself. Here is a more complex example:
Example 2.
mi sutra klama le blanu zdani be la djan. le briju
I quickly come to the blue house of John from the office.
More completely, this translates as:
I quickly (at doing something) come to the blue house of John from the office (of someone, at some location), via some route, using some means of travel.
In this example, one of the nested sumti selbri has had its places specified, while two places of klama have been elliptically omitted:
x1 of sutra klama contains mi (I)
x2 of sutra klama contains le blanu zdani be la djan. (the blue-house of the one named John)
x1 of blanu zdani contains the value which fills x2 of sutra klama; the thing which is a blue house
x2 of blanu zdani contains la djan. (the one named John)
x3 of sutra klama contains le briju (the office of someone, at some location)
The sumti for x4 and x5 of sutra klama are elliptically omitted.
Two of the places of the selbri in x3, briju, have also been elliptically omitted, and this is expressed in the more exact translation of the example.
Note that in the two tanru in example (2), sutra klama and blanu zdani, each of the four brivlamay be a self-contained selbri unit as well, having its own sumti attached to it (using the cmavo be). The place structure of the final component of a tanru (klama and zdani, respectively) becomes the place structure of the tanru as a whole, and hence the place structure of the higher level bridi structure. (The place structure of klama thus becomes the place structure of the sentence, while the place structure of zdani becomes the place structure of the x2 sumti.)
A brivla must have a single defined place structure, describing the specific sumti places to be related. If this were not so, example (1) might be interpreted arbitrarily; for example, as "The person is the means, the office the route, the market is the time of day, the house is the cause, by which someone elliptically unspecified comes to somewhere (also elliptically unspecified)." Not only is this nonsense, but it is confusing nonsense. With fixed place structures, a Lojbanist will interpret example (1) correctly. A Lojbanist can also, incidentally, express the nonsense just quoted. It will still be nonsense, but it won't be the syntax that confuses the listener; each place will be clearly labelled, and the nonsense can be discussed until resolved.
Thus, for a given brivla, or indeed for any selbri, we have a specific place structure defined as part of the meaning. Complex selbri, described below, simply have more elaborate place structures determined by simple rules from their components.
The place structure of a bridi is defined with ordered (and implicitly numbered) places. The sumti are typically expressed in this order. When one is skipped, or the sumti are presented in a non-standard order, there are various cmavo to indicate which sumti is which.
Lojban bridi are most often given in a sentence as the value of the 1st (x1) sumti place, followed by the selbri, followed by the rest of the sumti values in order. This resembles the English Subject-Verb-Object (SVO) sentence form. It is shown schematically as:
or abbreviated as:[sumti]x1 [selbri] [sumti]x2 [sumti]x3 ... [sumti]xn
x1 selbri x2 x3 x4 x5
This is the order used for the bridi sentences in examples (1) and (2). However, it is equally correct and straightforward to place the selbri at the end of the bridi:
x1 x2 x3 x4 x5 selbri
There are a variety of cmavo operators which modify these orders, or which modify one or more pieces of the bridi. These can make things quite complicated, yet simple rules allow the listener to take the complications apart, piece by piece, to get the complete and unique structure of the bridi. We cannot describe all of these rules here, but a couple of key ones are given.
Of these cmavo, cu is placed between a selbri and its preceding sumti in a sentence-bridi. cu cannot be used if there are no sumti before the selbri; but otherwise it is always permitted though not always required. Example (1) shows a cu used that is required; example (2) optionally omits the cu. Skill in Lojban includes knowing when cu is required; when it is not required but useful; and when it is permitted, but a distraction.
What happens when the place structure of a given bridi does not exactly match the meaning that the speaker is trying to convey? Lojban provides a way to adapt a place structure by adding places to the basic structure. The phrases that do so look exactly like sumti, except that they have a cmavo marker on the front (called a modal tag, or sumti tcita) which indicates how the added place relates to the others. The resulting phrase resembles an English prepositional phrase or adverbial phrase, both of which modify a simple English sentence in the same way. Thus I can say:
Example 3. ca le cabdei mi cusku bau la lojban.
ca le cabdei = an added sumti; modal operator ca indicates that the added place specifies 'at the time of...', or 'during...'; thus 'during the nowday', or 'today';
x1 = mi (I)
selbri = cusku (x1 expresses x2 to x3 in form/media x4)
x2, x3, and x4 are elliptically omitted;
bau la lojban = an added sumti; modal operator bau indicates that the added place specifies 'in language...'; thus 'in language which is called Lojban'.
The sentence thus roughly translates as "Today, I express [it] in Lojban."
Among additional bridi places that can be specified are comparison, causality, location, time, the identity of the observer, and the conditions under which the bridi is true. In Lojban, semantic components that can apply to any bridi, but are not always needed for communication (for instance, location and time), are left optional.
As described above, the simplest form of selbri is a brivla. The place structure of the brivla is used as the place structure of the bridi. Various modifications can be made to the brivla and its place structure using cmavo. These include ways to treat a single selbri as a state, an event, an activity, a property, an amount, etc. For example, jetnu, a selbri expressing that x1 is true, becomes the basis for ka jetnu, a selbri expressing the property of truth.
Place structures of a selbri can undergo 'conversion', which is simply a reordering of the sumti places. Since the listener's attention is usually focussed on the first and/or the last sumti expressed in the bridi, this has a significant effect in relative emphasis, somewhat like the 'passive voice' of English (e.g. The man was bitten by the dog. vs. The dog bit the man.)
As shown in example (2) above, tanru can also be selbri. These tanru can be composed of simple brivla, brivla modified by the techniques referred to above, or simpler tanru. tanru themselves can also be modified by the above techniques.
All of the possible modifications to selbri are optional semantic components, including tense. (Time and location, and combinations of the two, can be incorporated as tenses in the selbri.) With tense unspecified, examples (1) and (2) might be intended as past, present, or future tense; the context determines how the sentence should be interpreted.
sumti can be compared to the 'subject' and 'object' of English grammar; the value of the first (x1) sumti place resembles the English 'subject'; the other sumti are like direct or indirect 'objects'.
But as the discussion of bridi above will have indicated, this is only an analogy. sumti are not inherently singular or plural: number is one of those semantic components mentioned above that is not always relevant to communication, so number is optional in Lojban. Thus, example (2) could have been translated as We quickly go/come/went/came (etc.) to the blue houses of those called John. If this is plausible given the context, but is not the meaning intended, the speaker must add some of the optional semantic information like tense and number, to ensure that the listener can understand the intended meaning. There are several ways to specify number when this is important to the speaker; the numerically unambiguous equivalent of the English plural people would be: le su'ore prenu ('the at-least-two persons').
There are a large variety of constructs usable as sumti, beyond what we have already seen. Only the most important will be mentioned here. These include:
cmavo which serve as short representations for longer sumti expressions (e.g. ko'a 'He/She/It1', ti 'this'); imperatives are also marked with a pro-sumti (ko 'You!');
back references and forward references to other sentences and their components (e.g. ri 'the last complete sumti mentioned', di'u 'the preceding utterance');
grammatical Lojban text, or text in other languages, suitably marked to separate the quote from the rest of the bridi (e.g. zo djan 'The word John', lu mi klama li'u 'The Lojban text mi klama', zoi by. I go .by. 'The non-Lojban text I go');
reference to something by using its label; among other things, this allows one to talk about another sentence ("That isn't true"), or the state referred to by a sentence ("That didn't happen"), unambiguously in all cases (e.g. la'e di'u na fasnu = "The referent of the last sentence does not occur", or "That didn't happen");
reference to something named by using the name (e.g. la djan 'John', lai ford. '[the mass of things called] Ford');
reference to something by describing it (e.g. le prenu 'the person', le pu crino 'the thing that was green in the past', le nu klama 'the event of going').
Pro-sumti, anaphora/cataphora, and indirect references are all equivalent to various uses of pronouns of English, and we won't be going into any further detail here. Quotations and named references are straightforward, and quite similar to their English counterparts. Lojban , however, allows a distinction between Lojban and foreign quotation, and between grammatical and ungrammatical Lojban quotation.
Descriptions appear similar to an English noun phrase (le prenu = 'The person'). For most purposes, this analogy holds. The components of a description are a 'descriptor' or gadri, and a selbri. As we've seen, by default such a sumti refers to what would be put into the x1 place (the 'subject') of its selbri. Thus le klama is 'the go-er (to some place from some place via some place, using some means of travel)', and le blanu is 'the blue thing'. With conversion, as described above, a speaker can access other places in the bridi structure as the new 'subject' or x1 place: le se klama is "the place gone to (by someone from some place via some place, using some means of travel)". Descriptions are not limited to selbri with attached sumti; as in example (2), they can include bridi with places filled in.
Abstract bridi such as events and properties can also be turned into sumti. These are among the more common descriptions, and a common source of error among new Lojbanists. If le klama is 'the go-er/come-r (to some place from some place via some place, using some means of travel)', le nu klama is the 'event of (someone) going/coming (to some place from some place via some place, using some means of travel)'. The abstraction treats the bridi as a whole rather than isolating the x1 place.
Descriptions can also incorporate sentences based on abstracts; this is needed to elaborate sumti like le nu klama. For example, le nu mi klama ti is 'the event that: I come here (from some place via some place, using some means of travel)', or simply 'my coming here'.
In addition to number, Lojban allows for mass concepts to be treated as a unit. This is equivalent to English mass concepts as used in sentences like Water is wet, and People are funny. Mass description also allows a speaker to distinguish, in sentences like Two men carried the log across the field, whether they did it together, or whether they did it separately (as in "One carried it across, and the other carried it back.")
Sets can be described in sumti, as well as logically and non-logically connected lists of sumti. Thus, Lojban provides for: "Choose the coffee, the tea, or the milk", or "Choose exactly one from the set of {coffee, tea, milk}". Note that English connectives are not truly logical. The latter is the common interpretation of "Coffee, tea, or milk?" and is relatively unambiguous. The former, if translated literally into Lojban, would be a different statement, because of the ambiguous meaning of English or.
Finally, sumti can be qualified using time, location, modal operators, or various other means of identification. Incidental notes can be thrown in, and pro-sumti can have values assigned to them. Lojban also has constructions that are similar to the English possessive.
Free modifiers are grammatical constructs that can be inserted in a bridi, without changing the meaning, or the truth value, of the bridi. Free modifiers include the following types of structures:
Parenthetical notes, which can be of any length, as long as they are grammatical.
These are used for direct address; they include several expressions used for 'protocol', allowing for smooth, organized communications in disruptive environments (e.g. ta'a 'excuse me', be'e 'are you listening?'), as well as some expressions that are associated with courtesy in most languages.
These are comments made at a metalinguistic level about the sentence, and about its relationship to other sentences. In English, certain adverbs and conjunctions serve this function (e.g. however, but, in other words).
These are halfway between discursives and parentheses, and allow the speaker to make metalinguistic statements about a sentence without modifying that sentence. Thus, the discursive bridi equivalent of This sentence is false does not result in a paradox, since it would be expressed as a discursive bridi inside of another sentence, the one actually being described.
These are expressions of emotion and attitude about the sentence, being expressed discursively. They are similar to the English exclamations like Oh! and Ahhhh!, but they include a much broader range of possibilities, covering a range comparable to that expressed by English intonation; they can also serve as indicators of intensity. Also included in this category are indicators of the relationship between the speaker and the expression (evidentials). Found in native American languages among others, these allow the hearer to judge how seriously to take an assertion, by making explicit the basis for the speaker making the assertion: that the speaker directly observed what is being reported, heard about it from another, deduced it, etc.
The manner of asking questions in Lojban is quite different from English. In Lojban, most questions are asked by placing a question word in place of the value to be filled in by the person answering. The question word mo can be used in the grammatical place of any bridi, including those within sumti. It asks for a bridi (usually a selbri) to be supplied which correctly fills in the space. It is thus similar to English what? This booklet is titled la lojban. mo, meaning 'The thing called Lojban is what?', or, of course, 'What is Lojban?' The question word ma is used in place of a sumti in the same manner. Thus a listener can ask for ellipsis to be filled in, or can pose new questions that are similar to the classic English questions (who?, when?, where?, how?, and why?).
Yes/no questions can either be asked as a question of emotional attitude — such as belief, certitude, supposition, decision, approval, or intention — or as a question of truth and falsity. In the first case, the answer is an attitudinal. In the second case, the answer is an assertion or denial of the bridi being queried. Lojban also provides question words that can request a value filling many other grammatical functions.
The tense system of Lojban expresses not only the time at which something happens, but also the place. It can express very complex combinations of both temporal and spatial distances and directions (the time directions being 'past' and 'future', of course), interval sizes and ranges, and parts of events such as 'beginning', 'middle', and 'end'. Fortunately, this entire system is optional: it is perfectly correct to express bridi with no specific tense at all, in which case the place and time is up to the listener to figure out.
Some examples of tenses in use are:
Lojban supports all of the standard truth-functions of predicate logic. These can be used to connect any of several different levels of construct: sumti, bridi, selbri, sentences, etc.; the methods used indicate unambiguously what is being joined. As an example of English ambiguity in the scope of logical connectives, the incomplete sentence I went to the window and ... can be completed in a variety of different ways (e.g. ...closed it, ...the door, ...Mary went to the desk); in these, the and is joining a variety of different constructs. You must hear and analyze the whole sentence to interpret the and, and you still may not be certain of having a correct understanding. Lojban would make clear the structures being joined from the outset.
Another way Lojban supports logical connectives is by distinguishing them from non-logical connectives. The latter include:
the and of mixing (as in "coffee with milk" — which is neither just coffee nor just milk, but both at once);
expressions of causality (Lojban supports expression of four different kinds of causality: physical causation, motivation, justification, and logical implication);
and the various conjunctive discursives (such as but, and however), which in English imply 'and' without stating it.
Lojban has incorporated a detailed grammar for mathematical expressions. This grammar parallels the predicate grammar of the non-mathematical language. Numbers may be clearly expressed, including exponential and scientific notation. Digits are provided for decimal and hexadecimal arithmetic, and letters may be used for additional digits if desired. There is a distinction made between mathematical operations and mathematical relations. The set of operations is not limited to 'standard arithmetic'. Operations therefore assume a left-grouping precedence which can be overridden with parentheses, or optionally included precedence labels that override this grouping on evaluating the expression.
Included in Lojban are means to express non-mathematical concepts and quantities as numbers, and mathematical relationships as ordinary bridi. In Lojban, it is easy to talk about a 'brace' of oxen or a 'herd' of cattle, as well as to discuss the "5 fingers of your hand", or "∫ −2x3+x2−3x+5 dx evaluated over the interval of −5 to +5 bottles of water".
Note: In case you're curious: li ri'o ni'u re pi'i xy. bi'e te'a ci su'i xy. bi'e te'a re vu'u ci bi'e pi'i xy. su'i muboi ge'a xy.boi ge'a mo'e vei ni'u mu bi'o ma'u mu ve'o djacu botpi
The set of possible Lojbanic expressions is called selsku. Lojban has a grammar for multiple sentences tied together as narrative text, or as a conversation; the unambiguous Lojban grammar supports an indefinite string of Lojban paragraphs of arbitrary length. Using the rules of this grammar, multiple speakers can use, define, and redefine pro-sumti. Paragraphs, chapters, and even books can be separately distinguished: each can be numbered or titled distinctly. One can express logical and non-logical connectives over multi-sentence scope. (This is the essence of a set of instructions — a sequence of closely-related sentences.) Complex sets of suppositions can be expressed, as well as long chains of reasoning based on logical deduction. In short, the possibilities of Lojban grammatical expression are endless.