Been worrying about this since Northrop’s references to Aryan, and the 20th century “PC” difficulty of attributing the language to an Aryan “race”.
Since Sir William “Indiana” Jones proposed a common Aryan or Indo-European language in 1786, with linguistic similarities having been noted by European travellers as early as the 1500’s, the idea of a common “proto-indo-european” language (PIE) seems well established amongst linguists and historians. What is less clear is any agreement on the precise tree or hiearchy of which languages evolved from which, nor even whether repeat and reverse migrations and cultural influences, may have involved a more complex web rather than a simple tree.
Hindus may claim Sanskrit (refined, pollished, perfect – language of the gods) as the root. Europeans may claim Aryan (ie Iranian), Armenians may claim Aryan-Armenian, but most would agree a common PIE. What is clear is that there was a fluid Indo-European exchange of populations and culture, with common linguistic threads, that pre-dates greek, latin, and all the later romance and germanic european languages. Obviously the reason agreement is difficult is because much of this evolution pre-dates written history, and it seems (?) that the oldest written texts were the Sanskrit “Vedic” texts.
I guess the term Indo-European just avoids complicating the issue, where all that is inferred is their shared origins, in cases where precise historical sequence before the written texts is not relevant to the subject. Using Aryan (like using Sanskrit) confuses the issue with a paricular claim of aboriginality with a particular people at a particular time. Seems the proto-language and its migration east and west is generally accepted as arising 4000 BC in Anatolia / Armenia / Upper Tigris-Euphrates-Mesopotamia terrirory. Sanskrit’s claim to originality can only go back as far as 1500 BC and only as far as 100 to 200 BC in written form.