BOOK REVIEW / POLITICS : Right’s Take on Black ‘Blame’ Is Wrong : RACE AND CULTURE: A World View <i> by Thomas Sowell</i> ; Basic Books $25, 316 pages

Conventional wisdom has it that the Los Angeles riots exposed the great gulf between Simi Valley and South-Central--between white and black in American culture. Less well-known is that the unrest revealed an ocean of disagreement within the African American community itself.

On its left shore stood such leaders as Khallid Abdul Muhammad, who hailed the “Boston Tea Party” that he said followed the Rodney King verdict; on its right, leaders such as economist Walter E. Williams criticized the police for not being “out there with shoot-to-kill orders.”

Thomas Sowell’s new book is sure to only raise that ocean’s tides. A senior research fellow at Stanford’s Hoover Institution and arguably the most prominent African American conservative after Clarence Thomas, Sowell writes in the circumlocutory style of the dispassionate academic. His aim, he assures us, is not to judge disenfranchised Americans but to show how “a group’s own culture (is the) primary determinant of its economic and social fate.”

Still, that Sowell has an inflammatory mission is clear. You don’t have to be a cryptographer, for instance, to realize he is implicitly criticizing Native and African Americans with sentences like this: “Fertility rates, alcohol consumption, performance and behavior in school, suicide rates, and output per man hour . . . (are) just some of the indicators of behavioral differences among racial and ethnic groups.”

Sowell’s indictment-by-implication neatly gets him off the hook from having to back up his arguments with empirical evidence. But on the occasions when he does directly assert that a racial group is disenfranchised because of a weakness in its culture, he trots out statistics without revealing the story behind them.

For instance, to support his assertion that “there is reason to doubt whether various groups apply themselves equally to abstract thought,” he cites a study wherein “observers” found that “West African boys ‘obviously became bored’ with abstract questions.”

He fails, however, to tell us the nature of these questions or the way in which the “observers” defined abstract . Had the test measured sensitivity to genuinely African forms of abstraction--e.g. to the distinct polyrhythmic counterpoint of sub-Saharan music--then one suspects the boys would have been considerably less “bored.”

Similarly, Sowell cites a study by Robert M. Yerkes in which “American Negro soldiers tested during World War I tended to ‘lapse into inattention and almost into sleep’ during abstract tests.” What Sowell doesn’t reveal is that scholars have long dismissed as grossly racist Yerkes’ test--which branded blacks with an “average age of 10” and led Army researchers to evaluate African American intelligence partly on the basis of skin color.

Despite Sowell’s deceptive use of questionable statistics, one can’t dispute his central point: that some cultures have greater difficulty than others adapting to Western notions of progress and productivity.

Sowell vividly illustrates many of the barriers to this adaptation. He shows us how Africa’s isolating geography (it has few navigable rivers and accessible harbors) and lack of any common language deprived it of the trade in goods and ideas that invigorated Europe. Sowell’s sympathy for cultures that fail to “progress,” however, is sorely limited, for like the slave-born educator Booker T. Washington, he believes that no barrier is insurmountable.

Plenty of cultures, he emphasizes, have overcome geography (“Japan has prospered economically, despite being nearly destitute of natural resources, while many Third World nations languished in poverty on fertile land”), prejudice (despite their persecution during the Ottoman empire, Christians and Jews nevertheless “predominated in the commerce and industry of that empire”) and poverty.

He celebrates Mexican-Americans for not succumbing to poverty, pointing out that while they receive even less prenatal care than blacks, who have one of the nation’s highest infant mortality rates, their infant mortality rates are no higher than those of whites.

Here, however, is where the glibness in Sowell’s tendency to “blame” a single culture while ignoring its surrounding environment becomes most clear, for blacks and Latinos have experienced very dissimilar environments.

As public health scholars have shown, Latinos have done well at child care because, as voluntary immigrants, they have been able to maintain the intimate family support structures of their native land.

Most blacks, in contrast, historically have had little choice but to abandon their family ties--from the 17th Century, when they were forced to adapt to the slave trade, to the 1940s, when they were given the opportunity to leave Southern plantation homes for real jobs in the North.

So while Sowell excoriates African Americans for their failure to adapt to Western notions of “progress,” their family ties, at least, may have unfurled precisely because they adapted all too well.