Why did supernatural religion decline rapidly in western democracies, especially in America, in the past quarter-century?

Many sociologists attribute the transformation to prosperity, good health, and the governmental safety net. Affluent, secure, comfortable people have less urge to seek divine help, they contend. In contrast, religion remains strong in poor, unhealthy, less-developed places where life is difficult. (Perhaps this explains higher religiosity among African Americans, who can’t fully share the nation’s good times.) This theory seems plausible to me.

A different explanation is offered by social analyst Mary Eberstadt of the Faith and Reason Institute in Washington. Eberstadt contends that the sexual revolution weakened American families, making them less likely to be church stalwarts. She outlined her premise in How the West Really Lost God: A New Theory of Secularization and extended it in a new book, Primal Screams: How the Sexual Revolution Created Identity Politics.

The renowned sexual revolution of the 1960s and 1970s—triggered initially by the birth-control pill—gave women greater freedom and undercut old Puritanical taboos. Female careers became more common. Female college-going soared. Divorce lost much of its stigma. Indirectly, this eroded religion. Eberstadt explained in an interview:

Consider what often happens when parents divorce and children are put in custody arrangements where they see mom and dad on alternate weekends. This regimen alone throws a monkey wrench into the common Christian practice of churchgoing, because if mom and dad live in different places, it’s less likely that children will be taken consistently to the same church. … Family disruption breeds religious disruption.

She added:

By no coincidence, religious practice in many western precincts declines dramatically exactly alongside rising divorce rates and cohabitation rates and fertility decline and other proxies for the sexual revolution … Not having families or having loosely structured and smaller families appears closely tied to not going to church or believing in God.

Her explanation likewise seems logical.

I’d like to offer a third possible explanation: Maybe the fading of religion is tied to rising intelligence, better education, and greater science knowledge. Brainy people are less likely than others to believe in magical gods, devils, heavens, hells, miracles, prophecies, and other church dogmas.

Various studies find that doubters have higher IQ than religious believers do. Also, the Flynn Effect asserts that IQ averages climbed significantly, about three points per decade, in the latter twentieth century. Young people who were given tests from the past scored higher than the old 100-point norm. (Some recent findings imply that the Flynn Effect is reversing in some nations, but not in America.)

If smarter people doubt supernatural claims and Americans have gotten smarter, that’s a formula for church decline.

I hope some researchers explore whether better brainpower undercuts religion.