“Between the eighteenth and the nineteenth centuries a new perspective opened. The battle for Hebrew had been definitively lost. It now seemed clear that, even had it existed, linguistic change and corruption would have rendered the primitive language irrecuperable.
What was needed instead was a typology in which information about known languages might be codified, family connections established, and relations of descent traced. We are here at the beginning of a story which has nothing to do with our own.
“The Sanskrit language, whatever be its antiquity, is of a wonderful structure; more perfect than Greek, more copious than Latin, and more exquisitely refined than either, yet bearing to both of them a stronger affinity, both in the root of verbs and in the forms of grammar [ . . . ]
No philosopher could examine them all three, without believing them to have sprung from some common source, which, perhaps, no longer exists.” (“On the Hindus,” The Works of Sir William Jones, III, London 1807, 34-5).
Jones advanced the hypothesis that Celtic, Gothic and even ancient Persian were all related to Sanskrit. Note that he spoke not only of similar verb roots, but also of similar grammatical structures. We have left behind the study of lexical analogies, and are beginning a research on syntactic similarities and phonetic affinities.
Already in 1653, John Wallis (Grammatica linguae anglicae) had posed the problem of how one might establish the relation between a series of French words–guerre, garant, gard, gardien, garderobe, guise–and the English series–war, warrant, ward, warden, wardrobe, wise–by proving the existence of a constant shift from g to w.
Later in the nineteenth century, German scholars, such as Friedrich and Wilhelm von Schlegel and Franz Bopp, deepened the understanding of the relation between Sanskrit, Greek, Latin, Persian and German.
They discovered a set of correspondences in the conjugation of the verb to be in all these languages.
Gradually they came to the conclusion that not only was Sanskrit the original language of the group, its Ursprache, but that there must have existed, for this entire family, an even more primitive proto-language from which they all, Sanskrit included, had derived. This was the birth of the Indo-European hypothesis.
Through the work of Jakob Grimm (Deutsche Grammatik, 1818) these insights became organized in a scientific fashion. Research was based on the study of sound shifts (Lautverschiebungen) which traced how from the Sanskrit p were generated pous-podos in Greek, pes-pedes in Latin, fotus in Gothic, and foot in English.
What had changed between the utopian dream of an Adamic language and the new perspective? Three things. Above all, scholars had elaborated a set of scientific criteria.
In the second place, the original language no longer seemed like an archeological artifact that, one day, might actually be dug up. Indo-European was an ideal point of scholarly reference only.
Finally, Indo-European made no claim to being the original language of all humanity; it merely represented the linguistic root for just one family–the Aryan.”
Umberto Eco, The Search for the Perfect Language, translated by James Fentress, Blackwell. Oxford, 1995, pp. 103-5.