Sin س

Sin is the twelfth letter of the modern Arabic order and the fifteenth of the older abjad order, from which it takes the numeral value sixty. It is written as three short teeth running into a shallow bowl that drops below the line, and it joins on both sides, keeping only the three teeth at the beginning and in the middle of a word. In several hands the teeth are flattened into a single horizontal stroke, a variation that is a matter of style rather than of spelling. The same skeleton carrying three dots above is shin.

Sin is a sun letter, so the lam of the definite article assimilates to it. Its sound is the voiceless alveolar sibilant, the s of English, and it is distinguished from the emphatic sad by the position of the tongue rather than by any mark on the page.

Its place in the inherited sequence is where the Semitic alphabets become difficult to line up. Sin holds the fifteenth position and the numeral value sixty, which in Hebrew belong to samekh, while its name resembles that of shin. The sibilant letters underwent shifts of sound and of name across the Semitic languages that scholars reconstruct in more than one way, and no single mapping of Arabic sibilants onto Hebrew ones satisfies both the names and the values. The atlas records the position and the value, which are stable, and does not assert a name derivation for sin. Sin appears among the fourteen letters that stand disjoined at the head of certain suras.

The alphabets of Hebrew, Arabic, Syriac, Samaritan and Mandaic all descend from one twenty-two letter sequence, and for most letters the correspondence is straightforward. Arabic ba is Hebrew bet is Syriac beth, in the same position, with the same numeral value and a recognisably related name. The sibilants, the s-like consonants, are the exception, and they are the standing hard problem of comparative Semitic epigraphy.

The difficulty has two halves. The first is that the ancestral language had more sibilant sounds than its daughters kept, and different daughters merged different pairs, so a letter that wrote one sound in one language writes another in the next. The second is that the letter names moved separately from the letter shapes and the letter values. In Arabic the letter called sin occupies the slot that Hebrew fills with samekh, a name it does not resemble, while the name it does resemble, shin, belongs to a different Arabic letter with a different value.

Several reconstructions of how this happened have been proposed and they differ on which merger came first and on what the original sounds were. This is a live scholarly disagreement rather than an unexamined gap: the evidence is the inscriptional record and the comparative phonology, both parties to the argument work from it, and the argument continues.

The atlas therefore treats the numeral values and the ordinal positions as settled, because they are directly attested, and treats the name correspondences of the sibilants as unsettled. Where a letter has a secure inherited name, such as ba from beth or ra from resh, that is recorded. Where it does not, nothing is asserted in place of it. Inventing a correspondence to complete the pattern would produce a tidier table and a false one.