A man who knows where the pleasures of language lie or lay

WORDS AND RULES By steven Pinker Basic Books 348 pp., $26

Steven Pinker, a professor in the Department of Brain and Cognitive Science at the Massachusetts Institute of Technology, studies how the mind works by examining the nature of language. In "Words and Rules," he examines irregularities, especially irregular verbs and plurals, from the points of view of biology, child development, psychology, philology, philosophy, and linguistics.

He looks in detail at how children learn regulars and irregulars, and he examines how the frequency or infrequency of the use of a verb affects whether or not it remains irregular. Oddly, children who make errors by substituting regular past tenses of verbs for the correct irregular ones - saying "singed" instead of "sang," for example - still object to adults doing the same thing.

Some verbs, according to Pinker, have become irregular recently, largely because of analogies with other irregulars. He claims, for example, that "snuck" is becoming standard as a past tense of "sneak," despite the wincing of purists. Other verbs exist in both regular and irregular past tenses. An example is "dived" and "dove." Similarly, "hung" and "hanged" are both past tenses of "hang," but the latter usage is limited to the form of execution.

Clearly, Pinker is fascinated by language, but his real interest is the human mind and how it works. His final conclusion is that "words and rules give rise to the vast expressive power of language, allowing us to share the fruits of the vast creative power of thought."

Perhaps the chief pleasures of this book do not lie in his overall theories of language, as much as in his delightful sense of humor and his individual explanations of how the language works - and why.

This book will be of interest to anyone fascinated by language, anyone who relishes multiple examples of each notion of its workings, anyone with the time and patience to move slowly through it, enjoying its delights on the way.

*Paul O. Williams taught English at Principia College for 22 years.

(c) Copyright 1999. The Christian Science Publishing Society