Babe Ruth is probably history's most famous professional baseball player. When his name arises, it is unlikely that the conversation will include mention of his religion — Catholic. But when the name of another famous baseball player, Hyman (Hank) Greenberg arises, his religion — Jewish — is almost always part of the conversation.

That reality fascinates Minneapolis author John Rosengren, who has published a previous book about baseball and another about hockey. The more Rosengren learned about the Detroit Tigers slugger, the more Rosengren wanted to know about Greenberg (1911-86), including the religious angle. Like previous Greenberg biographers, Rosengren could not separate Greenberg from his religion. (For example, Mark Kurlansky's biography of Greenberg published three years ago by Yale University Press was advertised as part of its "Jewish Lives" series.)

In fact, the final sentence of Rosengren's main text refers to Greenberg as "the greatest Jewish baseball player of all time." If he had been writing about another professional athlete, would Rosengren have referred to "the greatest Lutheran football player of all time" or "the greatest female Buddhist sprinter of all time"?

Probably not. And therein lies a dilemma for biographers: Is it intellectually proper to write a life using a stereotype as the structure? The stereotype in this instance: Jews are people of intellect and people of commerce, but not athletes. Like many stereotypes, that one contains kernels of truth and perniciousness.

As a biographer myself, I am uncertain whether the question can be answered "correctly." What I do know is that Rosengren has researched and written a first-rate biography of a professional athlete who was also an interesting human being off the playing field — and interesting in part because an entire religion looked to him to ameliorate its unhappy history of persecution. That is a huge burden to place upon an individual simply because he could hit and catch baseballs better than 99 percent of everybody else.

When Jackie Robinson broke through the racial barriers erected by Major League Baseball, he had to carry the gigantic burden of "representing" all African-Americans in the minds of passive and active bigots. Race is clearly a sensible demographic to write about because it is usually visible. Religion usually is not.

HANK GREENBERG

Rosengren opens the book with Greenberg in the Detroit Tigers clubhouse, debating whether to play a scheduled game against the Boston Red Sox on Sept. 10, 1934, or stay home to observe the Jewish holiday of Rosh Hashana. That difficult decision sets the stage for Rosengren to place Greenberg's life in the context of anti-Semitism, as Adolf Hitler abroad and the Ku Klux Klan at home made that mental disease difficult to ignore. To the extent Greenberg functioned so well professionally and personally within a poisoned world, he deserves to be called a "hero."

Steve Weinberg is a biographer in Columbia, Mo.