ATTACK OF THE KILLER SYNSECTS: REVIEW

If Mr. [Stanislaw Lem] were using these reviews of nonexistent books merely to explode human inanities and malignities, his performance, however brilliant, would soon grow tiresome, since the immediate targets are, after all, decoys of his own careful fashioning. But there is a deeper purpose at work here, one well served by [Catherine S. Leach]'s lucid translation. While expounding on the limitations of the statistical method in the first review, Mr. Lem takes care to inform the reader that precisely this method lies at the core of modern science. ''That flimsy determinism of the nineteenth-century rationalists has collapsed and will rise no more,'' he tells us; ''it was replaced, with unexpected success, by probability theory and statistics.'' A grasp of these same subjects turns out to be necessary if we are to understand why synsects make better weapons than supercomputers and superbombs. IN the last review, of a book titled ''The World as Cataclysm,'' Mr. Lem drops the mask of the ironist to offer a dazzling summary of the latest theories of the scientific cosmologists. Readers whose world views were shaped by the physics they learned even a few years ago in high school or college may find this updated cosmology shocking. The universe seems to have evolved through a process that Mr. Lem calls ''creation through destruction.'' A series of almost unimaginably violent events created our sun, our planet and perhaps intelligent life itself; any search for purpose or order in the location and timing of these events is bound to be frustrated. The universe, according to Mr. Lem, is governed by chance - a statement that he defends in a brilliant passage of detailed scientific explication that ranges from the roulette tables of Monte Carlo to the ''corotational circle'' of our galaxy, the Milky Way.