Religious belief spreads culturally only when sincerity is publicly displayed, not merely claimed.

Evidence

Last, a close cousin of apatheism is InCREDulous atheism. This term of course draws on the work of Joseph Henrich, who, you might recall, coined the term CREDs (credibility-enhancing displays), to point out that many of the extravagant practices and rituals found in prosocial religions and other cultural groups serve a persuasive function. When observers witness acts that reveal sincere commitment or belief—that is, when actions speaker louder than words—they are more inclined to see these beliefs as genuine and more willing to adopt them. In turn, this causes them to display the same CREDs to others. In this way, repeated waves of belief-behavior packages may turn into cultural epidemics. This is what we mean when we say religion spreads in a population. But when children grow up in families with parents who claim to be Christian but hardly ever spend a Sunday morning at church, they are less likely themselves to feel or express religious fervor. There arises a reverse cascade of irreligion. Consistent with this, anthropologist Jonathan Lanman studied the reasons behind the decline of religion in Scandinavia, and found that adults who recalled being raised by such parents—even if the parents claimed to believe in God—grew up to be nonbelievers. — Norenzayan, Ara, Big gods - how religion transformed…, 623

Categorization

• DEFINE: Defines CREDs and inCREDulous atheism, key mechanisms for how belief propagates or collapses.
• XREF: Directly inverse of the Big-God mechanism in this same book; the reader’s core interest is how visible displays (like trampling the fumi-e) enforce or destroy belief.