Scholars sent to colonial positions in the British Empire noticed something recognizable in the exotic languages they encountered. At the end of the eighteenth century, the English scholar, judge and diplomat William Jones, when working in India, noticed certain features in the vocabulary and grammar of Sanskrit that were shared with Latin and Greek and the modern European languages. In particular, he noticed certain words, like Sanskrit raj, Latin rex, German reich, and Celtic rix, that seemed similar in sound and meaning (they were all words for king or ruler).
If you look at some cognates like the following, you might come to the same conclusion:
Sanskrit Greek Latin Gothic Englishpita pater pater fadar father padam poda pedem fotu foot He also noticed certain grammatical features, like forms of the verb to be, that were shared in different languages. Jones supposed that these various languages must have descended from an original tongue. In 1799, he identified the tongue as Sanskrit, but later – in 1782 – he got to believe that Sanskrit, Greek and Latin all came from a common source, which had disappeared. This language is now known as Proto-Indo-European. It is thought that a group of people called the Kurgans spoke this language and lived in what is now southern Russia from some time after 5000 BC. In about 3500BC the Kurgans probably began to spread west across Europe and east across Asia. As groups of the Kurgans travelled further and further away from each other, they began to develop stronger differences in their dialects. With the passing of the time these dialects became different languages.
How then can we say anything about a language which existed more than 6000 years ago, before the time of written language? The answer comes from the study of so-called cognates, words of common origin in different languages. These words often resemble each other, and differences that exist between languages tend to be systematic. The scientific method that investigates cognates in order to reconstruct an original Indo-European form is the comparative historic method.
The comparative historic method-the reconstruction of earlier forms of a language, or of earlier languages, by comparing surviving forms in recorded languages.
The comparative method is based on some steps to be followed in the application of it, which are as follows:
1. Assembling cognate lists – comparing phonemes and morphemes in related languages on the basis of comparing meaningful units. It is supposed hypothetically that these units have common ancestors.
2. Establishing regular correspondence between compared units. Once cognate lists are established, the next step is to determine the regular sound correspondences they exhibit. The notion of regular correspondence is very important here: mere phonetic similarity, as between English day and Latin dies (both with the same meaning), has no probative value. English initial d- does not regularly match Latin d-, and whatever sporadic matches can be observed they are due either to chance (as in the above example) or to borrowing (e.g. Latin diabolus and English devil, both ultimately of Greek origin). But English and Latin do exhibit a very regular correspondence between t- and d-. For example: