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Phonetics and Phonemics in Historical Linguistics-I
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ceded -by all. Most linguists would choose such symbols for their reconstructed phonemes as would indicate their phonetic values also, rather than work with purely arbitrary signs. What is important is to know how far the phonetic aspects of the phonemes are essential, in theory, for reconstruction as such and, in a wider context, for the proper understanding of the history of the language.
: The only way in which we can trace the history of a language or a group of related languages is to compare the phonemic systems of the language at two different stages in its growth, which is admittedly continuous. In the comparative field, we compare the phonemic systems of a language with the phonemic system of the lost parent language which is reconstructed with the help of other languages of the same family. Naturally, the main purpose of this procedure is to make understandable the continuous change that has occurred in the language, as far as our sources allow us to do it. Obviously to trace the gradual manner in which the sounds of the language have changed and its sound-system is modified, is more likely to help our understanding of the change than ideas of a sudden replacement of one phoneme by another or the transformation of one phonemic system into quite a different one. What we do, when we compare the phonemic systems found at different stages in the life of a language, is to compare the initial point and the end result of a number of changes (may be wholly or partly phonetic) that are going on all along throughout the period, and we do not follow the changes themselves. Even in the case of a phonemic change involving no phonetic change, it is patent that somewhere else in the language a phonetic change has occurred in that some phoneme is either added or lost. An explanation of this type of change would naturally require an insight into the other phonemic changes which are based on real phonetic changes.
An actual example may help us to understand what is meant by the contention that phonemic changes are made more comprehensible by insisting on the continuous phonetic changes underlying them. This is also likely to bring out one peculiarity of phonemic analysis, which is probably the cause of concealing the continuity or gradualness of change in language.
The phonemic analysis of the vowels of the Old Indo-Aryan (DIA) offers no great difficulty. We have three vowels i, u and a which occur both short and long, and length is phonemic. /iti/ contrasts with siti/; /uru/ with /ūru/ and /vara/ with /vāra/. We have two mid vowels e and o which occur always long and two diphthongs ai and au. A number of alternatives are