The Logical Language Group, Inc. takes great pride in announcing the publication of The Complete Lojban Language, by John Woldemar Cowan. ISBN 0-9660283-0-9.

The Complete Lojban Language is a complete description of the artificial language Lojban. It serves as a reference grammar for the language, offering an overview of the language, as well as linguistic details on every aspect of the language. This book serves as the standard defining the language design. That design has been declared frozen for a minimum 5 year period; anyone who learns the language from this book can be assured that it will not be continually changing.

An online draft version is available. A list of CLL, aka Reference Grammar, Errata is also available, most of which have been approved by the book's author.

Though this description may sound imposing, technical and formal, the book is written in a light, often humorous style that teaches the reader about the Lojban language, about logic, and about linguistics in general.

Lojban is a current version of Loglan, the artificial language project described in the June 1960 Scientific American article of that name. "Loglan" was also referred to by name in Robert Heinlein's classic novel The Moon is a Harsh Mistress, as well as in other novels.

Loglan/Lojban is a language designed for several purposes, including linguistics research (especially involving a proposed test of the Sapir/Whorf hypothesis), foreign language instruction, artificial intelligence research, machine translation and related human/computer interaction applications, and as a stimulating educational and entertaining mental exercise. Some people are interested in Lojban as a prospective international auxiliary language. An international community of aficionados has appeared, writing in and about the language, primarily on the Internet.

The book is in hard cover, 620 pages long, and includes a thorough index.

Direct (prepaid) orders to our organization will be accepted at the price of US$25 plus shipping and handling.

How to Buy

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    The Logical Language Group, Inc.
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Our processing time (that is, the time between when you order a book and the time when we ship it) is 2-4 weeks. We are an all-volunteer organization. Please let us know if there is some kind of urgency in your order.

There is a $5 net discount on shipping costs for multiple book orders within the US only.

Please note that shipping orders to continents other than North and South America takes 4-8 weeks plus our processing time.

General Information

The Logical Language Group, Inc. is a tax-exempt 501(c)(3) scientific- educational organization, and donations may be tax deductible within the U.S. We acknowledge all donations over $250 in accordance with IRS regulations, and other donations by request.

Please make your donations by sending a cheque to the address above, or by donating through PayPal to the LLG.

We can accept Internet advance orders via e-mail, but you must followup with verification via postal mail or telephone within 2 weeks. No C.O.D. orders. We require prepayment on purchase orders.

Queries should be addressed to the LLG Secretary at the above address or via email to

Ongoing Work

Other than fixing errata for this edition (mentioned above), ongoing work on the CLL includes: