You know you're in trouble when a novel leads off with a tendentious authorial forward that tells you how to read the book you've just opened. ``Rat is not exclusively a book about animals, even though such an interpretation may also be acceptable. On the contrary, it is a novel about the laws that govern society, about our mythologies, our truths and lies, about love and hope, loneliness and nostalgia.'' Zaniewski, a Polish poet and academician, clues us in thusly--but the book he delivers is in fact none of this at all. It's the endlessly belabored story of a rat: a running, copulating, baby-eating rat; a pig-stealing, chicken-snatching, and--on occasion--people-plaguing rodent that is forever chased, reviled, and seeking safety. The rat, as rats go, is believable enough- -horrifying, in other words--but there's not much that can be done with him other than to get him (rather incredibly) onto various trains and boats or into secret passageways that provide a change of scene for the most brutishly circumscribed of existences. A war is also going on among the humans--occasioning lots of blood drinking (a point about as subtle as a cleaver). And when the rat actually encounters a piper (``From the level of a bookshelf, you watch the man holding to his lips a long black pipe, from which issue the tones that transform you, alter you, vanquish you. Petrified, motionless, stunned, I listen to the music as if it were a dream, although it isn't a dream''), you want to squeak and moan yourself at the desperate artifice. It isn't often that you actually wish there were a greater measure of anthropomorphism in an animal allegory, but you do here. Blunt and boring.