Jonathan Franzen's new novel,

Farrar Straus Giroux. 562 pp. $28

So what is it about Jonathan Franzen and poo? In 2001, his wonderful breakthrough novel, "The Corrections," was momentarily stunk up by a scene in which a senile old man imagines his feces talking back to him. A decade later, Franzen's more staid, more mature, but all around less exciting "Freedom" reaches its comic zenith when a young man searches through his own excrement with a fork. What seemed like a sophomoric indulgence in that earlier tour de force now smells stale.

Which is one of the problems with "Freedom." We've read this story before in "The Corrections," back when it was witty, when its satire of contemporary family, business and politics sounded brash and fresh, when its revival of social realism was so boisterous that it ripped the hinges off the doors of American literature. The most anticipated, heralded novel of this year gives us a similarly toxic stew of domestic life, but Franzen's wit has mostly boiled away, leaving a bitter sludge of dysfunction.

Cannily, the slyest part comes up front: a 23-page preface that outlines the rise and fall of Walter and Patty Berglund's marriage in St. Paul, Minn. (You may have read this section last year in the New Yorker.) "Walter's most salient quality, besides his love of Patty, was his niceness," Franzen writes, while Patty was "a sunny carrier of sociocultural pollen, an affable bee . . . famously averse to speaking well of herself or ill of anybody else." It's classic Franzen, a smart, acidic take on suburban life and particularly green yuppies, "the super-guilty sort of liberals who needed to forgive everybody so their own good fortune could be forgiven; who lacked the courage of their privilege."

This finely fanged tale of neighborly spite and camouflaged jealousy lets you relish your own superiority -- if you don't recoil at the narrator's smugness, which is perhaps what always separates Franzen's fans from his detractors. (Paradoxically, the New York Times critic whom Franzen called "the stupidest person" in the city thinks "Freedom" is a limning, lapidary masterpiece.)

But even readers won over, as I was, by the opening summary of the Berglunds' collapse will be flummoxed by the novel's next section: a long reminiscence supposedly written by depressed, alcoholic Patty at the suggestion of her therapist. She describes her crippling adolescence with her caustic father and unavailable mother, and then her messy relationship with the two men who will dominate the rest of her life: the "miraculously worthy" Walter, whom she eventually marries, and his best friend, Richard Katz, a rakish musician who disdains popular acclaim the way a certain National Book Award-winning writer once sneered at Oprah's praise.

All of this -- Patty's college basketball career, her abusive friends, her ricocheting attraction to Walter and Richard -- is analyzed with the microscopic attention of a determined autopsy. It's often odd enough to justify such scrutiny, but there's no way to believe that this acerbic, incisive voice belongs to Patty, as opposed to, say, Jonathan Franzen. The obvious falseness of that pose, which we're repeatedly reminded of, is fatally distracting.

When Franzen drops the Patty mask around page 200, we can finally enjoy his exquisite sentences without reservation. Love him or hate him -- the critical extremism he inspires demands that everybody pick a side -- you've got to admit he's an extraordinary stylist, America's best answer to Martin Amis. In dialogue that conveys each palpitation of the heart, every wince of the conscience, and especially in those elegantly extended phrases of narration, Franzen conveys his psychological acuity in a fugue of erudition, pathos and irony that is simply fantastic.

But how many readers, even the long-suffering readers of literary fiction, will settle for linguistic brilliance as sufficient compensation for what is sometimes a misanthropic slog? What else does "Freedom" offer as it churns over the detritus of one middle-class family?

Unfortunately, the novel doesn't offer its themes so much as bully us into accepting them with knife-to-the-throat insistence. The word "freedom," for example, beats through the book frequently enough for a frat-house drinking game. As the characters attain the freedom they craved -- from children, from spouses, from work -- they inevitably discover that it's unsatisfying and self-destructive, which is the same puritanical sermon that Amis pounded away on earlier this year in his cerebral sex farce, "The Pregnant Widow."

One of the reasons liberty is so fleeting, Franzen argues, is that our relations are characterized by Darwinian competition. Again and again, we hear that Richard and Walter are competing for Patty, that Patty and Walter's assistant are competing for Walter, that Patty and her sisters are competing for their parents, that Walter and Patty are competing for their son's affections. It's a bleak, relentlessly cynical view of human nature acted out by self-loathing men worshiped by female doormats. (Where are all these pretty women who plead, "You don't have to love me . . . I can just love you"? Give me names!)

The overdetermined competition between these characters is reflected by the novel's overarching concern with environmental destruction, the lopsided contest between the animal kingdom and humanity's ever-growing population. That alarm becomes Walter's rallying cry as he tries to manage a shady partnership involving a West Virginia coal mining company and a vast nature preserve.

It's the kind of complex, contemporary issue that Franzen can trace with precision, catching the ironies and moral compromises that take place in boardrooms and bedrooms, administrative offices and country hollows, the great knot of economic and political machinations that somehow entangles the fate of an endangered warbler with the manufacture of military hardware. And it's nicely laced with wry, up-to-the minute commentary on social media, alternative music and youth activism.

But far too often, Franzen uses Walter's environmental work to arrest the story, turn toward the audience and hector us about the loss of wildlife, particularly the extinction of songbirds. In the unlikely event that some strip-mining, ocean-dumping, panda-hunting rube stumbles onto this novel, he'll get his comeuppance for sure, but everybody else will probably use these cranky public service announcements as a chance to stretch their legs. Same for the book's worn-out satire of Republicans and the Iraq war, which hangs on the wholly unbelievable involvement of Walter's son with a corrupt Halliburtonesque corporation. Oddly discordant with the story's sophistication, these corny bits are like watching Dick Cheney shoot fish in the face in a barrel.

But stop with the complaints! The point to remember is that "Freedom" is big enough and thoughtful enough to engage and irritate an enormous number of readers, even those who couldn't care less (guilty!) that Franzen -- along with a pelican, the pope and a black pug -- has appeared on the cover of Time magazine this summer.

As the sprawling epic winds down, it recasts the opening comedy of suburban conflict in a new neighborhood carved out of Walter's precious forest. Decades have passed by now; Walter and Patty's children have grown up and moved away; affections have been crushed. But Franzen allows a twilight of peace and redemption that's lovely, almost magical. One more thing for us to argue about in this brilliant, maddening novel.

Charles is the fiction editor of Book World. You can follow him on Twitter at http://www.twitter.com/roncharles.