Isthmian script
The Isthmian script is an early set of symbols found in inscriptions around the Isthmus of Tehuantepec, dating to, though with dates subject to disagreement. It is also called the La Mojarra script and the Epi-Olmec script.
It has not been conclusively determined whether Isthmian script is a true writing system that represents a spoken language, or is a system of proto-writing. According to a disputed partial decipherment, it is structurally similar to the Maya script, and like Maya uses one set of characters to represent morphemes, and a second set to represent syllables.
Recovered texts
The four most extensive Isthmian texts are those found on:- The La Mojarra Stela 1
- The Tuxtla Statuette
- Tres Zapotes Stela C
- A Teotihuacan-style mask
- A few Isthmian glyphs on four badly weathered stelae — 5, 6, 8, and probably 15 — at Cerro de las Mesas.
- Approximately 23 glyphs on the O'Boyle "mask", a clay artifact of unknown provenance.
- A small number of glyphs on a pottery-sherd from Chiapa de Corzo. This sherd has been assigned the oldest date of any Isthmian script artifact: 450–300 BCE.
Decipherment
The following year, however, their interpretation of the La Mojarra text was disputed by Stephen D. Houston and Michael D. Coe, who had tried unsuccessfully to apply the Justeson-Kaufman decipherment-system to the Isthmian text on the back of the hitherto unknown Teotihuacan-style mask.
Along with proposing an alternative linguistic attribution of Epi-Olmec writing as proto-Huastecan, Vonk argued that the size of the corpus compares unfavorably in comparison with the rate of repetition within the corpus, so that a unique decipherment is simply impossible given the current state of affairs. He goes on in illustrating the principal applicability of readings in random Old and New world languages to demonstrate the coincidental nature of any such proposals.
The matter is still under discussion. In Lost Languages Andrew Robinson summarises the position as follows: