Kurt Vonnegut, whose dark comic talent and urgent moral vision in novels like “Slaughterhouse-Five,” “Cat’s Cradle” and “God Bless You, Mr. Rosewater” caught the temper of his times and the imagination of a generation, died Wednesday night in Manhattan. He was 84

Like Mark Twain, Mr. Vonnegut used humor to tackle the basic questions of human existence: Why are we in this world? Is there a presiding figure to make sense of all this, a god who in the end, despite making people suffer, wishes them well?

The defining moment of Mr. Vonnegut’s life was the firebombing of Dresden, Germany, by Allied forces in 1945, an event he witnessed firsthand as a young prisoner of war. Thousands of civilians were killed in the raids, many of them burned to death or asphyxiated. “The firebombing of Dresden,” Mr. Vonnegut wrote, “was a work of art.” It was, he added, “a tower of smoke and flame to commemorate the rage and heartbreak of so many who had had their lives warped or ruined by the indescribable greed and vanity and cruelty of Germany.”

Mr. Vonnegut said in the prologue to “Timequake” that it would be his last novel. And so it was.

His last book, in 2005, was a collection of biographical essays, “A Man Without a Country.” It, too, was a best seller. In concludes with a poem written by Mr. Vonnegut called “Requiem,” which has these closing lines:

When the last living thing
has died on account of us,
how poetical it would be
if Earth could say,
in a voice floating up
perhaps
from the floor
of the Grand Canyon,
“It is done.”
People did not like it here.