Psi ⲯ

Psi is the twenty fourth letter of the Coptic alphabet and carries the numeral value seven hundred; Coptic Orthodox usage names it epsi. Like ksi it writes a cluster of two consonants rather than one, standing for p followed by s, and like ksi it is optional, since Coptic may spell the two letters out instead. That makes psi one of the rarer characters on a Coptic page in its phonetic role, while its numeral duty at seven hundred is entirely steady. It belongs with ksi, theta, phi and khi in a group of Greek letters whose usefulness to Egyptian was never obvious, and what Coptic did with that group is one of the more revealing things about how the script was settled.

The tradition did not prune the Greek alphabet down to the letters Egyptian needed. It kept the series whole, complete with letters that write clusters, letters for sounds Egyptian lacked, and three signs that write nothing at all and exist only for counting, and it then added seven letters of its own at the end. An alphabet assembled that way records its history in its shape, and a Coptic alphabet chart read from left to right is a summary of where the script came from. There is an instructive contrast here with alphabets that were designed rather than assembled. Glagolitic, devised in the ninth century for a specific mission, has a letter for each sound the language needed and very little that is redundant, because one person settled it at one time for one purpose. Coptic looks nothing like that, and the difference is not a matter of quality. An assembled alphabet carries its history in its irregularities, and a designed one does not.

Psi is the penultimate letter of the Greek derived part of the Coptic alphabet, with only omega after it, and it is a convenient place to take stock of what that part contains. Twenty four letters came from Greek, in the Greek order, with the Greek numeral values, and a twenty fifth sign, sou, was inserted at the sixth position for counting alone. Of those twenty five, some went straight into heavy native use because Egyptian had the sounds: alpha, ei, eta, iota, kappa, laula, me, ne, ou, pi, ro, semma, tau, omega. Some found almost no native work and live in loanwords: gamma, delta, zeta. Some write clusters and are optional: ksi, psi.

Some double as compressions with the Egyptian letter hori: theta, phi, khi. And one, sou, writes nothing. After omega the alphabet changes character entirely, because the next seven letters are Egyptian, taken from Demotic, carrying Egyptian names and writing Egyptian sounds that no Greek letter could reach, and carrying no numeral value because they were never part of the Greek series the values came from. That break in the middle of the alphabet chart is the whole story of the script in one line, and it is visible to anyone who looks at the chart, although nothing on the chart itself announces it.