THE OPENING QUESTION : POWERSHIFT <i> By Alvin Toffler (Bantam: $22.95; 592 pp.)</i>

Alvin Toffler’s world is so rocked by “powershifts,” you’d think he was writing on the San Andreas Fault: “We live at a moment when the entire structure of power that held the world together is now disintegrating. . . . We stand at the edge of the deepest powershift in human history. . . . Gone is the proletariat; now welcome the cognitariat.”

None of us “cogs” wants to be stranded on the wrong edge of the Shift, of course, and so it’s not difficult to see why this breathless book is being translated into 11 languages while its author lectures in America’s top boardrooms, including the White House. Hopefully, though, our fear of being technophobic Luddites won’t lead us to forget that writers have been mistaking technological change for social change since the Industrial Revolution.

Toffler proves no exception: “Powershift” totters on tired theories (the move from societies based on mineral to those based on mind), obvious aphorisms (“Governments controlled or heavily influenced by extremists . . . do not stay democratic long”) and cryptic observations: “Campuses are stirring from Berkeley to Rome and Taipei, preparing to explode.” Berkeley, preparing to explode?

Most questionable is Toffler’s implicit assumption that new technologies usually work in favor of the common man. He argues, for example, that computers are helping “thoroughly smash” the knowledge monopoly of Western managers and specialists, leading to a democratization of power. But in focusing on medicine, the evidence he cites is unconvincing: True, anyone now can access professional databases such as “Index Medicus,” but medical texts have never been inaccessible to lay people, just incomprehensible; true, patients now sue their doctors more often, but this has less to do with their growing knowledge of human physiology than with lawyers’ greater zeal; true, nurses are demanding more respect, but this is mostly made possible by a critical nursing shortage.

“Powershift” continues in this vein, distorting dozens of other trends until they fit one of its simple paradigms. Toffler’s canvass is admittedly broad enough to daunt the best of us, but its ultimate lack of coherence ironically disproves one of its main assumptions: that a mere abundance of information will lead us to knowledge and thus power.