The following is a quote from Wikipedia under the heading "Sanskrit" and the subheading "European scholarship".
European scholarshipEuropean scholarship in Sanskrit, begun by Heinrich Roth (1620–1668) and Johann Ernst Hanxleden (1681–1731), is regarded as responsible for the discovery of the Indo-European language family by Sir William Jones. This scholarship played an important role in the development of Western philology, or historical linguistics.
Sir William Jones, speaking to the Asiatic Society in Calcutta (now Kolkata) on February 2, 1786, said:
The Sanskrit language, whatever be its antiquity, is of a wonderful structure; more perfect than the Greek, more copious than the Latin, and more exquisitely refined than either, yet bearing to both of them a stronger affinity, both in the roots of verbs and in the forms of grammar, than could possibly have been produced by accident; so strong, indeed, that no philologer could examine them all three, without believing them to have sprung from some common source, which, perhaps, no longer exists. end quote.
I especially like the comment "indeed, that no philologer could examine all three(Greek, Latin and Sanskrit), without believing them to have sprung from some common source, which, perhaps, no longer exists." In thinking more about this one wonders about precursor civilizations like Atlantis, and Mu and Lemuria, all of which by legend were sophisticated enough for travel between the stars.