LIFE ON THE SCREEN: Identity in the Age of the Internet. By Sherry Turkle. Simon & Schuster. 347 pp. $25

The wonders of cyberspace have made a believer of Turkle, a social scientist at MIT and a practicing psychotherapist. Yet despite her affinity for the net-surfing world view, she has lost neither her "real-life bias" nor her ability to communicate with those too uninformed, or skeptical, to take life at interface value.

In nontechnical language, she describes how the Internet has transformed the computer screen into a gateway, a beckoning path to virtual worlds in which people may play at identity, freely altering their personality, status, vocation, and sex.

For Turkle, the promise of such "Internet experiences" is that they can "help us to develop models of psychological well-being." "Like the anthropologist returning home from a foreign culture," she writes, "the voyager in virtuality can return home to a real world better equipped to understand its artifices."

Yet Turkle also describes the danger: that the boundary between real life and simulation will be blurred or erased. Her book is a Baedeker less to the bizarre electronic landscapes of cyberspace than to the minds of those who wander through them. As such, it is instructive, amusing, and chilling.

-James Morris