Illustrated. 395 pp. New York: Broadway Books. $24.95.
….”Like the wheel or the telephone,” Sacks writes, ”the alphabet was an invention to change the world.” While it’s true that billions of people use writing based on phonetics every day, not everyone believes the invention was an advance in literacy. Darnell, who discovered the earliest known alphabetic writing, told me in an e-mail message that combining ideographic and phonetic symbols, as in ancient Egyptian writing, ”provides much more information than an alphabetic system, and allows for additional levels of poetic expression” compared with phonetic letters alone. Indeed, as most e-mailers know, when pictographs known as ”smileys” — horizontal images that hint at facial expression — are added to text, the nuance of a sentence can change. A wink-smiley — ; ) — added after ”you are bad” changes its meaning entirely.