THE £ SIGN ON MY computer keyboard recently stopped working. Now I must either cut and paste it from a file of symbols, or type “pounds”, which is tedious and “25 pounds” instead of “£25” looks wrong. Each occasion is a reminder that six phonetic signs (p, o, u, n, d, s) from the 26-letter English alphabet are required to do the work of one, word-sign (£): a concept referred to as a logogram (from the Greek logos, “word”).

Although English text is chiefly alphabetic, it has more logograms than most of us realise. Think of punctuation marks such as ? and !, numerical symbols such as 2.5 and 487, the arithmetical signs + and % and the ampersand & and the @ in email addresses. They are all logograms.

We call our writing system an alphabet, but it is a mixed alphabetic/ logographic system. It could just about function if we got rid of all logograms, but would be very inefficient.

Logograms form an invaluable shorthand. None is pictographic: their shapes give no clues to their meanings. The £ symbol is not a stylised drawing of, say, a metal coin or a wad of banknotes. Perhaps it might be easier to remember if it were. Pictographic icons are certainly popular with the designers of word-processing software and websites. A drawing of a paper clip represents an attached file in an email; a rubbish bin indicates where to put some junk mail.

But pictograms can also be ambiguous. I recall a “fish-in-a-suitcase” sign at San Francisco airport, which was apparently intended to mean “Fish to Go” (a fish takeaway). What does the red flag in my inbox mean? That there is an urgent message waiting? No, it signifies a message requiring nonurgent attention.

The Highway Code is a superb example of a system that mixes pictograms with the alphabet. One mugs up the meaning of road signs for the driving test from written descriptions, but on the highway, the signs prompt one’s memory through pictography.

From the early third millennium BC, Ancient Egyptian hieroglyphs mixed logograms – many graphically pictorial – with an “alphabet” of 24 phonetic letters standing for consonants. In the exquisite cartouche of Tutankhamun, there are three pictographic logograms: the heraldic plant symbolises “Upper Egypt”, the column symbolises “Heliopolis”, a city near modern Cairo, and the shepherd’s crook symbolises “ruler”. The other signs are phonetic, but, almost as if to confuse people used to abstract alphabetic symbols, the phonetic symbols are pictographic, too. Thus the loaf of bread (a half-circle) stands for “t”, the chick bird for “w”, and the water (a wavy line) for “n”.

If one studies all writing systems, ancient and modern – from Mesopotamian cuneiform, Egyptian hieroglyphs and Mayan glyphs to Chinese characters, Arabic script and the English alphabet – it turns out that they share a single underlying principle: they mix phonetic symbols with logograms. That some of these logograms are pictographic, while most are abstract, is really a distracting sideshow; it is the mixture that matters.

Its proportions vary from system to system. Finnish is the most phonetic, Chinese the most logographic. English with a mere 26 letters and a few dozen logograms, has far more phoneticism than Chinese writing. None the less, a Chinese speaker, faced with an unfamiliar character, can sometimes guess its pronunciation, if not its meaning, by recognising its phonetic component.

So, though writing systems appear bewilderingly diverse, they are unified at the most fundamental level.

Andrew Robinson’s The Story of Measurement is published by Thames & Hudson on October 15

The Story of Writing: Alphabets, Hieroglyphs & Pictograms by Andrew Robinson
Thames & Hudson, £11.95; 232pp

Andrew Robinson appears at The Times Cheltenham Literature Festival on Wednesday October 10 at 4pm
Call 01242 227979
www.cheltenhamfestivals.com

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