America’s Christians and Jews will need a good deal of help from theologians and historians (and perhaps a little less help from polemicists and boosters) if they are to better understand the world’s Muslims, a group that includes, of course, many of their own fellow-citizens. All that will come, no doubt, but for now the social scientists of the Pew Forum offer us their assistance with “The World’s Muslims: Unity and Diversity,” the largest study of global Muslim belief ever undertaken.

The study, which collected 38,000 interviews in 80 languages, points to certain regional differences in intensity of belief and frequency of practice. It finds, among much else, that “Across the Middle East and North Africa . . . Muslims 35 and older tend to place greater emphasis on religion and to exhibit higher levels of religious commitment than do Muslims between the ages of 18 and 34. In all seven countries surveyed in the region, older Muslims are more likely to report that they attend mosque, read the Quran (also spelled Koran) on a daily basis and pray multiple times each day.”

More results here. The variations in religious attitudes that the study finds commend the classic picture of Muslim culture as a various “mosaic” that Carleton S. Coon first painted in his classic Caravan. Mass media has done as much to fracture as to unify Islam, which remains a various faith that cannot be boiled down to the views of any radical mullah or moderate reformer.