THE INDO-EUROPEAN SUPER-FAMILY OF LANGUAGES
Thomas V. Gamkrelidze and V. V. Ivanov
Linguistics, the scientific study of language, can reach more deeply into the human past than the most ancient written records. It compares related languages to reconstruct their immediate progenitors and eventually their ultimate ancestor, or protolanguage. The protolanguage in turn illuminates the lives of its speakers and locates them in time and place.
The science developed from the study of the Indo-European superfamily of languages, by far the largest in number of languages and number of speakers. Nearly half of the world's population speaks an Indo-European language as a first language; six of the 10 languages in which Scientific American appears—English, French, German, Italian, Russian and Spanish—belong to this superfamily.
Over the past 200 years, linguists have reconstructed the vocabulary and syntax of the postulated Indo-European protolanguage with increasing confidence and insight. They have tried to unravel the paths by which the language broke into daughter languages that spread throughout Eurasia, seeking at the origin of those paths the homeland of the protolanguage itself. The early investigators placed the homeland in Europe and posited migratory paths by which the daughter languages evolved into clearly defined Eastern or Western branches. Our work indicates that the protolanguage originated more than 6,000 years ago in eastern Anatolia and that some daughter languages must have differentiated in the course of migrations that took them first to the East and later to the West.
The reconstruction of ancient languages may be likened to the method used by molecular biologists in their quest to understand the evolution of life. The biochemist identifies molecular elements that perform similar functions in widely divergent species to infer the characteristics of the primordial cell from which they are presumed to have descended. So does the linguist seek correspondences in grammar, syntax, vocabulary and vocalization among known languages in order to reconstruct their immediate forebears and ultimately the original tongue.
Living languages can be compared directly with one another; dead languages that have survived in written form can usually be vocalized by inference from internal linguistic evidence. Dead languages that have never been written, however, can be reconstructed only by comparing their descendants and by working backward according to the laws that govern phonological change. Phonology—the study of word sounds—is all-important to historical linguists because sounds are more stable over the centuries than are meanings.
Early studies of Indo-European languages focused on those most familiar to the original European researchers: the Italic, Celtic, Germanic, Baltic and Slavic families. Affinities between these and the "Aryan" languages spoken in faraway India were noticed by European travelers as early as the 16th century. That they might all share a common ancestor was first proposed in 1786 by Sir William Jones, an English jurist and student of Eastern cultures. He thus launched what came to be known as the Indo-European hypothesis, which served as the principal stimulus to the founders of historical linguistics in the 19th century.