Because languages seem to evolve, spawn and even die, they can seem like a species of organic life by other means. And if the evolution of life-forms has been less than tidy and linear, so has the development of language, which is so irregular and filled with redundancies that many a rational animal has been driven mad by it–mad enough to try to build a new language from the ground up. To engineer, in other words, an intelligently designed one.

They’re called conlangs–constructed languages–and the linguist Arika Okrent has written a terrific book about them: In the Land of Invented Languages (Spiegel & Grau; $26). Conlangs can either be a priori (invented from scratch) or a posteriori (amalgamations of existing languages). They can be motivated by the desire for greater streamlining and logic (Blissymbolics, aUI, Lojban) or for social justice (Esperanto, Laadan). The earliest documented conlang is the Lingua Ignota of Hildegard von Bingen, a twelfth-century nun; the goofiest may be Solresol, a language based on the seven notes of the musical scale invented by Jean Francois Sudre in the 1830s; the most successful may be the language invented by Marc Okrand and trademarked by Paramount Pictures (Klingon).

There was a craze for conlangs in the seventeenth century, the age of "gentlemen inventors." John Wilkins, founder of the Royal Society and inventor of the glass beehive, among other things, kicked off the fad with Philosophical Language, a treatise on his own taxonomic system, in 1668. (Jonathan Swift lampooned this tendency in Gulliver’s Travels, with the "grand academy of Lagado" devoted to abolishing unnecessary words.) In the nineteenth century it was fashionable to try to blend languages to promote ethnic unity, as in Pan-Slavism, or the melding of Arabic, Persian and Turkish known as Balaiban. In the mid-twentieth century, linguists were seized with a horror of "word magic," which advocated for linguistic hygiene: C.K. Ogden’s Basic English pared down our lexicon to 850 words, eliminating supposedly meaningless ones like "sin," "idea" or "rights." John Wolfgang Weilgart’s language was a "cure for diseases of the mind caused by language"; Count Alfred Korzybski’s Tyranny of Words claimed to cure alcoholism, homosexuality, frigidity and nymphomania, and to improve one’s finances.

Okrent’s book is a compilation of wonderful stories about batty inventors–some lovable, like Esperanto’s Ludwik Zamenhof, some not, like Blissymbolics’s Charles Bliss. Another of the book’s rewards is the way that Okrent, with a light touch, manages to interrogate the positivist’s creed that rationality is universal. But people who can’t agree on first principles will never come to the same conclusions. Therefore the question becomes: Whose first principles? Whose rationality?

If John Wilkins was the first man to attempt a purely logical language, he was the first failure as well: the point of language is to communicate, and his conlang was utterly unusable. A modern update, James Cooke Brown’s Loglan (from logical language), turned into Lojban. It may as well have been called Logjam: conversation in Lojban, according to Okrent, is very slow. "There are at least twenty ways to say ‘and’…. But that’s nothing compared to what happens when you get into ‘or’ and ‘if.’" Okrent gives a cursory example: if you want to say "John and Alice carried the piano," you would have to use an "and" construction that did not assume they were taking turns, or doing it in different spatio-temporal coordinates altogether. So you would use an "and" that specified John and Alice as a mass entity, but you couldn’t use this "and" to suggest they are friends–that would demand an "and" that considered them jointly but not as a mass entity. No wonder she says that going to a Lojban conference is akin to watching people do long division in their heads.

Okrent’s chapters on Blissymbols best illustrate the dangers of overestimating one’s own logic. Blissymbolics is a "pictorial symbol language" invented by Charles Bliss and expostulated in an 800-page tome published in 1949 called Semantography. Fascinated by Chinese characters and troubled by the tribal divisions fostered by language diversity (he was born in what is now Ukraine), he developed a logical system using a new pictorial language.

Bliss assumed that pictures are self-evident. If this were true, it wouldn’t be so hard to devise a hazard sign for nuclear waste that would be intelligible for 10,000 years, a problem that stumped the semiotician Thomas Sebeok. Nor would the linguist Daniel Everett have to teach members of the Piraha tribe to interpret drawings and photographs. Nor would users of American Sign Language or Nepali Sign Language have different meanings for the same sign. When teachers at the Ontario Crippled Children’s Centre (Bloorview Kids Rehab today) discovered, in the 1970s, that Blissymbols allowed them to teach language to kids with cerebral palsy, they made modifications that drove Bliss to distraction. Notwithstanding the fact that his language was a tremendous breakthrough for these teachers and their pupils, he fought them every step of the way. Okrent explains that when "the teachers encouraged the children to remember the symbol for ‘food’…by picturing it as a plate with a spoon under it, he was livid. It was crucial to his system that it be understood as the ‘mouth’ above the ‘earth’ because the true meaning (according to his ‘logical’ system) was ‘all food which our mouth takes from Mother Earth.’"

When is logic in the mind of the beholder? In Blissymbols, "shame" is the feeling you get when you are "unhappy because your mind thinks no! to what you have done." In John Weilgart’s pictorial language, aUI, shame is "toward-dark-feeling." Okrent observes: "Both Bliss’s and Weilgart’s symbols for shame ‘look like’ what they mean in some way, but there is nothing universal or self-explanatory about either one." Bliss knew not of what he pictured: shamelessly, he spent years harassing the one school that had found a purpose for his invention. (The school eventually settled a suit that allowed it to use the language in peace; a third party, Easter Seals, charitably stepped in and compensated Bliss to the tune of $160,000.) The desire for a rational language can coexist quite nicely with an irrational despotism.

Shirley McNaughton, who instituted Blissymbolics at the Ontario children’s center, is more of a language hero than any of the inventors. Her students, unable to communicate from birth, experienced an explosion of language skills when instead of being given pictures for things–toilets, food–they were given a basic set of symbols that allowed for combinations. Combinations allowed for a range of expression, and self-expression. "When a child wanted to say ‘dream’ but did not have a symbol for it on her board, she pointed to ‘sleep + think,’" Okrent reports. "Her teacher guessed from the context that she meant ‘dream,’ and the child confirmed that guess…. Communication had always been a guessing game for these children, but before Blissymbols they had no way to constrain the guesses." When Okrent asked a boy how he used to communicate before, he responded, "Kick." Orpheus subdued wild beasts with his lyre, but a child learns self-possession only by being able to sing, and speak, herself.

We can draw two related conclusions from Okrent’s story. First, the flexibility of language is its greatest asset for us. Through the "errors" of ambiguity and redundancy, we arrive with unexpected precision to new formulations about the world as we experience it. As Okrent wisely points out, "Not only do we ‘not know what thing the universe is,’ but we don’t know what assumptions we make about it."

The second conclusion is that usability will always trump logic. Usability is social, and the social realm is built on common assumptions that may or may not be "rational." The success of some conlangs, like Esperanto and Klingon, hinged on the community created by their users. The failure of others–like Suzette Haden Elgin’s feminist language, Laadan–was a failure of the same. Like other conlangs, Laadan attempted to eliminate a fundamental ambiguity of natural language: intention. At the outset of any utterance in Laadan, you must indicate whether you are forming a statement, a question, a command, a request or a warning, in whatever spirit you are making it–in anger, jest, fear or neutrality. Okrent explains: "In Laadan the ‘It wasn’t what you said, it was how you said it’ objection can’t be so easily dismissed." But what about occasions when you don’t want to signal your intention–as in flirting, joking, verbal jousting, fiction or poetry? Stripping language of surprise is the intended consequence of rational conlangs; stripping it of delight is the unintended one. In the end, humility may be the only rational response to the plenum of natural language. Delectation wouldn’t exactly be irrational, either.