9:30 p.m. NEW YORK -- Kurt Vonnegut, the satirical novelist who captured the absurdity of war and questioned the advances of science in darkly humorous works such as ''Slaughterhouse-Five'' and ''Cat's Cradle,'' died Wednesday. He was 84.

Vonnegut, who often marveled that he had lived so long despite his lifelong smoking habit, had suffered brain injuries after a fall at his Manhattan home weeks ago, said his wife, photographer Jill Krementz.

The author of at least 19 novels, many of them best-sellers, as well as dozens of short stories, essays and plays, Vonnegut relished the role of a social critic. He lectured regularly, exhorting audiences to think for themselves and delighting in barbed commentary against the institutions he felt were dehumanizing people.

''I will say anything to be funny, often in the most horrible situations,'' Vonnegut, whose watery, heavy-lidded eyes and unruly hair made him seem to be in existential pain, once told a gathering of psychiatrists.

A self-described religious skeptic and freethinking humanist, Vonnegut used protagonists such as Billy Pilgrim and Eliot Rosewater as transparent vehicles for his points of view. He also filled his novels with satirical commentary and even drawings that were only loosely connected to the plot. In ''Slaughterhouse-Five,'' he drew a headstone with the epitaph: ''Everything was beautiful, and nothing hurt.''

But much in his life was traumatic, and left him in pain.

Despite his commercial success, Vonnegut battled depression throughout his life, and in 1984, he attempted suicide with pills and alcohol, joking later about how he botched the job.

His mother had succeeded in killing herself just before he left for Germany during World War II, where he was quickly taken prisoner during the Battle of the Bulge. He was being held in Dresden when Allied bombs created a firestorm that killed an estimated 135,000 people in the city.

''The firebombing of Dresden explains absolutely nothing about why I write what I write and am what I am,'' Vonnegut wrote in ''Fates Worse Than Death,'' his 1991 autobiography of sorts.

But he spent 23 years struggling to write about the ordeal, which he survived by huddling with other POW's inside an underground meat locker labeled slaughterhouse-five.