Not, as you might expect, another book of recipes for soybean cutlets and granola. Barkas has written an engaging, idiosyncratic and downright scholarly book on vegetarianism as a religious, ethical and humanitarian creed from the days when Pythagoras railed against flesh-eating to the present when groups like the Hare Krishna are spreading the gospel. Barkas herself doesn't proselytize, even though (because?) she is certain that eventually the eating of meat, fish and fowl ""will be universally viewed with the same horror that is now attached to cannibalism."" Maybe so, but in the meantime she sets before us the testaments of famous herbivores: Tolstoy and Gandhi, Shelley and Wagner, Leonardo da Vinci, Hitler and the cantankerous G.B. Shaw. Invariably its champions have linked vegetarianism with longevity, non-violence, atheism and sexual abstinence, and sometimes with frequent bathing, socialism and nudity. And you'll read about some of the nuttier notions of some of the world's most brilliant cranks -- like Nietzsche, who wrote that ""A diet that consists predominantly of rice leads to the use of opium and narcotics.