Sometimes clunky and overreaching, sometimes piercing and compassionate, Philip Roth's vital new novel The Human Stain completes a postwar trilogy that includes 1997's Vietnam-era American Pastoral and 1998's anti-McCarthy diatribe I Married A Communist. As one of the few authors willing to consider the entire fabric of American life rather than simply picking at its stitches, Roth bends his story around the major issues of the day, taking on racial and ethnic identity, political correctness, and moral hypocrisy. Consider the central character of Coleman Silk, a septuagenarian classics professor who is less a full-bodied character than a vessel for Roth's loaded philosophies: Light-skinned black and Jewish, Silk can assume either guise when it suits him, until he ironically loses his post as dean of the privileged Athena College for allegedly using a racial epithet. His use of a single word, "spooks"used to describe a pair of students who never once attended class, and who turned out to be blackis turned against him in an absurd witch hunt. His main adversary is professor Delphine Roux, a bloodless French structuralist intent on exposing his misogyny and destroying his career without regard for the truth. She succeeds in pushing him into retirement, but her efforts continue when she discovers that Silk is having an affair with Faunia Farley, an illiterate janitor who is half his age and has suffered a history of abuse. As its double-meaning title implies, The Human Stain is both a mark on the skin and the mark of experience, too messy and convoluted to be sorted out by moral high-mindedness. At his worst, Roth hardly bothers to imagine ways to dramatize his ideas; one scene, a five-page rant about the Clinton-Lewinsky scandal, is staged as an overheard conversation among three strangers on a park bench. Yet as the novel gradually gains shape and depth, Roth's anger is parlayed into a sort of damaged humanism, as he fills in the complicated and ultimately sympathetic histories of each character. While his frequent alter-ego, Nathan Zuckerman, seems extraneous at first as Silk's hired biographer, his presence underlines what Roth sees as the author's role: to free the truth from ideologues like Roux and reveal it in all its cluttered, bountiful detail. For the most part, The Human Stain does exactly that.