useful in the decipherment of all kinds of scripts. They include collect- ing all available texts into a comprehensive and reliable text edition. In the case of the Indus script, the texts are being published both in photographs and in standardized, computer-drawn form.24) Concor- dances systematically recording all occurrences of individual signs and their sequences in the texts, and various other kinds of statistics have been prepared.25) Compilation of a reliable sign list, which distinguishes between distinct signs and their merely graphical variants, belongs to the most fundamental tasks.26) All these tasks are interrelated and affect each other, and revisions are required.
Fundamentally, there are two principal unknowns to be tackled in the decipherment of any ancient script, namely the script type and the underlying language or languages.
The Language Problem The language problem is most crucial. If the language of the Indus script belonged to a language family not known from other sources, the Indus script can never be deciphered. Compare the case of Etruscan: though written in an easily read alphabetic script, this isolated language is not much understood beyond the texts covered by copious transla- tions. But as the Harappan population numbered around one million, there is a fair chance that traces of the language(s) have survived in the extensive Vedic texts composed by Indo-Aryan speakers who came to the Indus Valley from Central Asia during the second millennium BCE.
Aryan languages have been spoken in the Indus Valley ever since, but an Aryan language could not have been spoken by large numbers of Mature Harappan people. The culture reflected in the Rgvedic hymns is quite dissimilar from the Indus Civilization. Particularly important is
______________________________ 24) For the first two volumes of the Corpus of Indus Seals and Inscriptions, see Joshi & Parpola 1987; Shah & Parpola 1991. The third volume is due to appear shortly.
For the time being, see Mahadevan 1977; Koskenniemi & Parpola 1979–1982.
For the present, see Parpola 1994: 68–82. Bryan Wells is preparing a new sign list
as his Ph. D. thesis (Wells 1998 is his M. A. thesis on the same topic).
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