Siddham Ja 𑖕

Ja is the voiced palatal and the third letter of its class, differing from the head of the class by voicing alone. It is common in the vocabulary, standing at the front of the words for birth and for conquest and of the large families of terms built on those roots, so a page of Sanskrit of almost any kind will carry it.

Its most consequential appearance is in a conjunct rather than alone. Joined to the palatal nasal that closes its own class, it writes the cluster that opens the Sanskrit word for knowledge, a term at the centre of Buddhist doctrinal vocabulary and consequently written in Siddham more often than almost any other. The conjunct has a shape of its own, and its pronunciation varies from region to region in India in ways that have nothing to do with how it is written.

Like the other letters of the class it takes the inherent short a and is read ja standing alone. The regularity that lets a reader predict its sound from its position, third slot, palatal class, voiced and unaspirated, is the property the East Asian students of the script valued most, because it made the table teachable to people who did not know the language.

The word for conquest built on this letter stands at the front of a long list of personal and monastic names, so a Siddham page carrying a colophon or a dedication is likely to use it even where the text itself does not. Names are a distinct layer of any manuscript and they are frequently the part hardest to establish, because nothing else in the text constrains them.

The transmission of Siddham eastward rests on a small number of long journeys. Chinese monks travelled to India to obtain texts, to study, and to settle questions that the translations available to them left open, and several of them wrote accounts of what they found. Xuanzang, in the seventh century, and Yijing, a generation later, are the best known, and both returned with manuscripts and with a first-hand knowledge of the language those manuscripts were written in.

Traffic ran the other way as well. Indian and Central Asian masters travelled to China and worked there, and in the eighth century three of them, Shubhakarasimha, Vajrabodhi and Amoghavajra, established the esoteric transmission at the Tang capital that Kukai later received. The texts on which Shingon rests were translated in that setting, by people for whom the Sanskrit original was not an abstraction.

What those journeys carried was not only documents but competence. A script cannot be transmitted by a manuscript alone, because a manuscript does not say how its letters are pronounced or how its conjuncts are resolved. It has to be taught by somebody who knows, and the chain of teaching that reaches Japanese Siddham runs back through these travellers to India. The letters survived in Japan because at each link somebody was there to explain them.