Summer is supposed to be the time for light reading. But this past week a slender book arrived that deals that with weighty matters. I found it impossible to put down and read it at one blow. It's called Rosenfeld's Lives. The author is Steven J. Zipperstein, a professor of Jewish culture and history at Stanford University.

Zipperstein's reconstruction of Isaac Rosenfeld's life is a minor masterpiece of biography. It is both beautifully written and meticulously researched. You might think that the topic of the New York intellectuals, who constituted what was once known as "The Family," would be exhausted by now, but it clearly isn't.

Rosenfeld, who grew up in Chicago, was a contemporary and close friend of Saul Bellow's. When Bellow received the Nobel Prize, he reportedly said, "It should have been Isaac." Rosenfeld appears in several of Bellow's novels as well as the short story "Zetland." But Bellow worked hard. Rosenfeld didn't. Rosenfeld squandered his talents, died at age 38, and became an object of scorn for many of the notoriously catty New York intelligenty, as they were once known.

But Zipperstein exhumes Rosenfeld's life to argue that there was more to it than that. A lot more. Rosenfeld was a child prodigy, who had mastered Kant by the age of 14. But his worldly success never seemed to match his abilities. He wrote a novel called Passage From Home, which dealt with the ties and struggles between Jewish fathers and sons. He also wrote numerous short stories. He was also a first-rate essayist. His credo was "Artists create their colonies. Someday these may become empires."

Zipperstein depicts Rosenfeld, who wrote a very amusing send-up of Kosher dietary laws in Commentary that created a scandal, as a precursor of Philip Roth. Rosenfeld also wrote about the fate of the Jews in Europe--something that most of the New York intellectuals preferred to treat with silence. After Auschwitz, Rosefenld, Zipperstein says, concluded in a powerful piece that appeared in the New Leader in 1948, that "the abstractions of the past--including belief in morality, the redemptive power of politics, the prospect of a good life on earth--are old, and decrepit." As Zipperstein shows, Rosenfeld embraced the life of the Village bohemians, and essentially went to seed.

But Zipperstein suggests that Rosenfeld might have pulled himself together had he not died an early death. His last published piece was one of his best, a short story called "King Solomon" and appeared in Harper's. Zipperstein observes that it is a "study of the slippage of youth, the sadness and perceptivesness that come from accumulated, mostly disappointing experience. And, oddly, it is also a tale of a man preparing to die." Zipperstein believes that a hale Rosenfeld might well have rebounded to become a leading intellectual during the 1960s, when many of the themes he had touched upon went mainstream.

It didn't happen. But should anyone really care about Rosenfeld's life or lives? One answer is simply that Zipperstein has rescued Rosenfeld from the condescension of posterity. But it's also the case that the 1940s and 1950s were, I think, the seedbed of current political fights, when the New York intellectuals drifted into hostile camps, particularly in the form of neoconservatism. These feuds have their origins in, and owe their intensity to, the literary and political battles of that era. No recent book that I've seen does a more astute job of explicating them than Zipperstein's fascinating study.