From Word Symbol to Phoneme Symbol
The second process, by which pictures cease to be ideograms and come to stand for specific linguistic forms, is even more important. The earliest Sumerian writings are just lists of objects with symbols for numbers against them: for example, four semicircles and the picture of an ox's head would read 'four oxen'. It seems that writing arose to meet the needs of the highly centralized city state, and the first writings are records of payments to the temple or city treasury, and similar transactions.
In this way, pictorial symbols come to stand for various words, which are the names of concrete objects like sheep, oxen, the sun, houses and so on. Next, by a process of extension, the same symbols are made to stand for more abstract words related to the original word. Thus a picture of the sun may come to stand for the words for 'bright', or 'white', and later for the words 'day' and 'time', and a picture of a whip for words like 'power' or 'authority'.
Perhaps the really crucial development, however, is 'phonetization', the association of a symbol with a particular sound (or group of sounds). First, a symbol for a concrete object is transferred to some more abstract object which is denoted by the same or a similar word. For example, the Sumerian word ti meant 'arrow', and so was represented by an arrow in the script; but there was also a Sumerian word ti which meant 'life', so the arrow symbol came to be used for this too. The arrow symbol was then felt to stand for the sound of the word ti, and was used for the syllable ti in longer words. In this way, the original word symbols developed into syllable symbols, which could be grouped together to spell out a word.
An analogous process in English can be imagined on these lines. A picture of a tavern is used to represent the word inn. Because of the identity of sound, the same symbol then becomes used for the word in. At the same time a picture of an eye is used for the word eye, and then by extension is used for the word sight. Finally the tavern symbol and the eye symbol are combined to write the words incite and insight, and have now become syllabic symbols. If we wanted to distinguish between insight and incite in our syllabic script, we could add a third symbol to show which of the two was intended: we could draw a picture of an orator to show that we meant incite, or add a symbol for some word like 'wisdom' to show that we meant insight. When we used the eye symbol by itself, we might wish to indicate whether it stood for the word eye or the word sight; one way of doing this would be to add a symbol after it suggesting one of the sounds used in the word intended: for example, if we had a symbol for the words sow, sew, so, we could add this after our eye symbol to indicate that the required word began with s. These and similar methods are used in ancient Egyptian and Sumerian writing.
Sumerian writing is very mixed, using ideograms, word symbols, syllable symbols, and various kinds of indicators of the types mentioned. Out of it, however, developed the almost purely syllabic system of cuneiform writing which was used for Akkadian (the language of the ancient Babylonians and Assyrians), and which for centuries dominated the writing of the Near East.
Ancient Egyptian writing also developed into a syllabic system, and was particularly important for the development of true alphabetic writing (i.e. a script that has symbols representing phonemes). The important thing about the Egyptian system was that the vowels were not indicated. Most of the signs (about eighty) stood for a group of two consonants, plus any vowels whatever. For example, the symbol for a house (par) stood for the group pr, and this could mean par, per, apr, epr, epra, and so on. But there were twenty-four signs which stood for only one consonant plus any vowel; for example, the symbol representing a mouth (ra) stood for the consonant r, and could mean ra, ar, re, er, and so on. When the West Semitic peoples living round the eastern shores of the Mediterranean developed a script, they did so by taking over from the Egyptians just these twenty-four signs. Originally, this must have been a syllable system, in which each of the signs stood for a number of possible syllables, like the Egyptian ra, ar, re, er, etc.: but in fact it is formally identical with a purely alphabetic system in which only the consonants are written and the vowels are left out.
The final step, of having fixed and regular symbols for the vowels, was made by the Greeks when they took over this Semitic alphabet. Some of the consonant sounds of Phoenician did not exist in Greek, and the Greeks used the corresponding symbols for vowels. For example, the first letter of the West Semitic alphabet, derived from the picture of an ox, was 'aleph', and stood for a kind of h sound (represented in the spelling by'); the Greeks of the period did not use this sound, and took the letter over as alpha, representing an a sound. Thus was reached at last a system of writing where symbols stand for phonemes, and all later alphabetic systems are ultimately derived from this Greek achievement. The great advantage of the system is the relatively small number of symbols needed, which makes universal literacy possible.
(From The Story of Language, by A. L. Barber.)