Religious belief self-enforces contracts better than secular institutions do

Evidence

The fact that Islam was also a religion and not merely a set of secular institutions further reduced the transaction costs of exchange. Islam was a powerful ideology with built-in sanctions which contributed to considerable self-enforcement of contracts. True believers had a non-material interest in holding to the terms of contracts even if the opportunity presented itself to shirk. All of this resulted in lower transaction costs associated with doing business among fellow Muslims, despite the enormous transportation and information costs involved, given the incredibly long distances and cultural barriers to be traversed across the Sahara and the rest of the continent. — Norenzayan, Ara, Big gods - how religion transformed…, 203

Categorization

• XREF: Directly instantiates Norenzayan’s larger Big God mechanism: belief supplies built-in supernatural sanctions (omniscient moralizing watchfulness) that substitute for external contract enforcement, exactly the mechanism the reader is mapping onto Rodrigues.
• DEEPTHINKING: The claim that belief’s built-in sanctions outperform secular institutions even where they’re cheaper in other respects gets to the core of why religion structurally underwrites long-distance cooperation.