Background:
Since the discovery of the Vedas and of the Avesta and since the decipherment of old Persian inscriptions and of the royal inscriptions of Aśoka,
modern scholarship has made efforts to distinguish and separate well-defined ancient languages and has tried to link these as discrete "entities" in a genetic tree.
This has been only partly succesful and we are left with several problems, including a considerable amount of linguistic evidence that has to be arranged in the category of "hybrid".
In the study linguistic evidence the view points of "entities", "waves" and "fields" have their value and their contribution to make to a better understanding.
Recent scholarship in emerging languages (H. Kloss, Ž. Muljačič, J. Goossens, and others) -- e.g. on the development of romance languages, and on the grammatical standardization of French and Dutch starting in the 16th century
(L. Maigret, H.L. Spiegel), that of English ONE century later (unless we count W. Bullokar's rudimentary Pamphlet on Grammar and Amendment of Orthography) and that of German some TWO centuries later (J.C. Adelung) -- has reached a level of maturity which makes it now possible to shed new light on the linguistic evidence of some of the most ancient testimonies of Indian and Indo-European ritual, religious and philosophical poetry and literature.