Mexico's Nobel Prize-winning poet and essayist meditates on the Marquis de Sade and his writings. Paz (Sor Juana, 1988; The Light of India, 1997; etc.) discovered Sade when he went to Paris in 1946. Simultaneously repulsed and fascinated by the eponymous father of sadism, the poet found in him a figure crucial for the modern world. In 1947 Paz wrote a poem, ""The Prisoner,"" as a somewhat begrudging homage but also as an inverted votive offering to the demon that had begun to haunt his imagination. ""Where are the borders between spasm and earthquake/eruption and copulation?"" he wonders. The poem is the first item included in this very brief book. Second comes an essay, ""Metaphors,"" which Paz wrote in 1961. Here the writer seeks heroically (if also inadequately) to define Sade's place in the order of things. Though not systematic at all, the essay coruscates with lightning bolts of insight. He shrewdly distinguishes between sexuality and eroticism, devoting his thought especially to the latter. Unlike mere sexuality, the erotic is fluid and always changing. It belongs as much to our imaginative as to our bodily lives and thus, suggests Paz, lies ""beyond"" fixed principle. It cannot be defined, yet it defines us. Our passions, he comments, are ""more powerful than our character, our habits, or our ideas, they are not ours. We don't possess them, they possess us."" The final piece, a short memoir of those days in Paris and people with whom he discussed Sade, adds little to the central essay but is pleasant to read. Paz's sober inquiry into the weirdness and horror of Sade does not titillate, seek to shock, or flirt with kinky absurdities. Paz meets the Sadean challenge with uncommon intelligence and intellectual maturity. Though tiny, Paz's new book admirably questions and explores the meaning of a figure who will not leave us alone.