Linguists interested in understanding this vast reservoir of linguistic wealth have had to face the problem of the near impossibility of settling any question concerning relatedness of languages with any degree of finality. Even basic questions such as whether all Indian languages devolved from a common ancestor continue to be debated today. The classifications that are generally accepted today have gained ascendancy primarily because of the authority of scholars such as Sapir and Powell, and not because of any corroborating evidence from archaeological findings. Indeed, Sapir himself asserted that linguistic analysis is the best approach for understanding the immigration patterns of early Americans. For these reasons, historical linguistics has become a paradigm of the way postmodernists, with their deeply impoverished understanding of science and technology, view knowledge: as a social construct based ultimately on authority and speculation, with no possibility of objective, independent truth. For the same reason, scientists view historical linguistics as mere social studies, based ultimately on authority and speculation, and therefore unrelated to science at all -- that is, well-suited to its role of providing descriptive documentation of cultural phenomena, but incapable, in its current state, of producing many solid conclusions. This deficiency is compounded by the evident difficulty, or perhaps unwillingness, of comparative linguists to make appropriate quantitative measurements of much more than a rudimentary statistical nature.
It helps to be mindful, therefore, when considering the possible interrelatedness of any particular set of American Indian languages, of these uncertainties and controversies that besiege this poor, unwanted orphan that is historical linguistics, because the disputes have no doubt contributed a great deal to the enthalpic flux within what is nonetheless a potentially highly relevant and important field. While non-linguists are most familiar with the tripartite classification of Indian languages into Eskimo-Aleut, Na-Dene, and Amerind or "other", in fact there are at least 150 different language families in the Western Hemisphere among which linguists cannot demonstrate any significant genetic relatedness.
The main part of the book discusses language families in North, Central, and South America, including the Chibchan, Arawakan, Eyak-Athabaskan, Uto-Aztecan, Siouan, Mayan, and Otomanguean families. The variation among these languages is tremendous. Many have tones, like Scandinavian or Sinitic languages, yet are highly inflected. Pomoan languages, for example, had a large number of subordinate verbal suffixes, including one that tells whether the subjects of the main and subordinate verbs are the same or different. Other languages, such as those of the Otomanguean family in Mesoamerica, are monosyllabic with CV syllables. The Apachean branch of Athabaskan languages, consisting of Navajo and the Apache languages, is interesting because they are quite recent creations, having arrived in the American southwest around 1500. Like most other Athabaskan languages, they lack labial sounds (b, m, or w).
Because of the huge number of languages, however, the languages are not discussed in anything approaching a systematic manner. Only the briefest summaries are given. This approach does not give enough information to allow the readers to understand the differences among the languages. For example, Proto-Mayan is described as being an ergative language with VOS word order, but even this basic property of word order is not given for most other languages. A table would have helped. The few written language forms, such as Mayan hieroglyphics, are only discussed in passing. One is left with a feeling that the subject is so vast and the methodology so inadequate that the author has despaired of ever making sense of it.
The rest of the book is a discussion of the many problems encountered in attempts to classify American languages, including those found in Greenberg's multilateral method, and also mentions some of the more improbable claims made over the years, such as supposed similarities between American Indian languages and Basque and between Nahuatl and Greek. The last chapter provides 27 maps showing linguistic regional areas, mostly taken from the Smithsonian's Handbook of North American Indians, which depict hundreds of language areas, giving the maps a paint-by-numbers appearance, and clearly illustrate the incredible complexity of the subject.