Recently Rajesh Rao et al applied statistical tests to Indus scripts and concluded that the script has the same entropy as a linguistic system; this contradicted the “illiterate Harappan theory” which has been in circulation since 2004. Previously too scholars disagreed with the “illiterate Harappan theory” and have published point-by-point rebuttals, but this new statistical analysis added fuel to the fire. This research, which got extensive coverage, was called “useless”, “trivial” and proponents of the illiterate theory lamented about the reviewing practices of science journals.
Now Rajesh Rao et al. takes on their critics with a new paper to be published in Computational Linguistics (H/T Rajesh P N Rao). They make it clear that without a full decipherment, the linguistic hypothesis or non-linguistic hypothesis cannot be proved. What they claim is increasing evidence for the linguistic hypothesis.
If the Indus script does encode language, what might the content of the inscriptions be? A majority of the Indus texts are found on stamp seals (Figure 1(a)), which were typically used in Bronze Age cultures for regulating trade. Seals were pressed onto clay used to seal packages of goods. Indeed, a number of such clay tags have been found at various sites in the Indus civilization, bearing seal impressions on one side and impressions of woven cloth, reed matting or other packing material on the other. These archaeological observations suggest that the short Indus texts on seals (Figure 1(a)), like their other Bronze age counterparts, probably represent the contents, the origin or destination, the type or amount of goods being traded, name and title of the owner, or some combination of the above. Similar linguistic explanations can be found for the inscriptions on other media.
If, on the other hand, as Sproat and colleagues propose, the script merely represents religious or political symbols, one is hard pressed to explain: (1) how and why were sequences of such symbols, with syntactic rules entropically similar to linguistic scripts (Figure 1(b)), used in trade in a manner strikingly similar to other literate Bronze age cultures? and (2) why did the Indus people use these symbols in consistent sequences in their native region and alter their ordering when in a foreign land (Figure 1(c))? As pointed out by other authors [ Mahadevan2009, Parpola2008, Vidale2007], such incongruities are more the norm than the exception if one accepts the nonlinguistic thesis espoused by Sproat and colleagues. The principle of Occam’s razor then suggests that we reject the nonlinguistic hypothesis in favor of the simpler linguistic one.[Entropy, the Indus Script, and Language: A Reply to R. Sproat]