Visionary literature, indeed. What Silverberg means is ""Eight Sci-Fi Stories That Blew My Mind,"" and he should have said so less pretentiously. The focus is admittedly subjective, but the stories themselves are terrific. There is a Cordwainer Smith novella, ""The Dead Lady of Clown-Town,"" written with the usual self-conscious intonations but beautiful enough to wring tears from the grimmest Smith-hater. There is James Blish's famous ""Common Time,"" an exquisitely disturbing glance into the spiritual intentions of Something waiting for us out there. And there is a jarring, elegant jape--about ecstasy and escape and prices that must be paid--that is arguably the best thing R. A. Lafferty has ever done. Wonderful contributions as well from Jack Vance, J. G. Ballard, and Silverberg himself. A smashing anthology.