Andrew M Riggsby (University of Texas at Austin)
Metrological standardization in the ancient Mediterranean and Near East has often been understood as a gesture of political domination (e.g. Cuomo 2007; Chambon 2011; Fanton 2019). Alternatively, it has been treated as a quasi-natural trend towards increased economic efficiency (e.g. Morley 2014; Bresson 2016). This paper questions the assumptions underlying both interpretations by considering two instances of what might be expected to be the most extreme cases of either scenario—systemic metrological reforms, that is deliberate change to multiple forms of measurement (rather than just, for instance, the weight standard). Systemic reforms have been identified with varying degrees of certainty in Ur, Judah, Archaic Athens, Persia, and Republican Rome, but only the first and last have contemporary documentation (the Hellenistic Athenian reform recorded by IG II2.1013 is not systemic despite occasional modern descriptions as such). The evidence from these well attested cases shows that casual application of either generic hypothesis can be misleading or even simply wrong.
The biographical preface of the law code of Ur-Nammu (lines 135-49; Wilcke 2002) gives considerable detail on that king's reforms among his prior acts, and Festus (288L = RS #46) preserves what appears to be much of the text for the enabling legislation in the Roman case (the lex Silia). Ur-Nammu reports that he established three exemplars for volumetric measurement all in stipulated ratios to a notional base unit. He then established a weight standard on the basis of the volumetric standard. No means of enforcement are specified. The lex Silia defines several volumetric measures in terms of weights of wine. Magistrates are to be punished if they deviate from these standards in the creation of future exemplars.
As a technical matter, Ur-Nammu's system has numerous practical failings. It creates separate (and therefore potentially inconsistent) standards; it defines weight in terms of volume, even though the latter is easier to calibrate; finally, it defines smaller units in terms of larger ones, which also creates calibration difficulties. This does conform to the standard ideological reading (consider the display value of "too many" standards that are each "too large" and of a system that is somewhat opaque), but not the conventional economic one.
The lex Silia's approach is technologically better suited to consistent standards, but there are two related points to be made about how that technology is used in practice. First, it guarantees ultimate availability of uniform standards, but not of private copies, nor does it create an independent incentive for the use of the system at all. As a practical matter, this should have some economic efficiency value, but an attenuated one. Second, the penalties are not directed at merchants or even forgers, but at future magistrates unilaterally adjusting standards. Authority being asserted, but it is not that of the ruler or the state as against the community, but that of the state (or even the community) against particular elite officials.