Nathan Nunn on the Paths to Development

Episode Summary

Executive Summary: Nathan Nunn argues that Africa’s development is shaped by deep historical persistence—state formation, the slave trade, geography, and institutions—though these forces interact with contemporary policy and culture. He emphasizes that patterns explain levels, not deterministic outcomes, and that education, infrastructure, and stronger informal/formal institutions can still shift trajectories.

Main Topics: Historical persistence and African development (Priority: 5/5): Nunn explains how state formation, colonialism, and the slave trade leave long-run effects on income, trust, and institutions, while stressing that persistence is probabilistic rather than deterministic. The slave trade, trust, and population patterns (Priority: 5/5): He argues that regions heavily exposed to slave raiding developed lower trust and different settlement patterns, including movement away from coasts and rivers and toward mountains for protection. Botswana, Ethiopia, DRC, and within-Africa heterogeneity (Priority: 4/5): The conversation uses specific countries to test persistence: Botswana as a success case, Ethiopia as a state-formation case, and the DRC as an example of historic state strength yet contemporary poverty. Institutions, contract enforcement, and trade/FDI (Priority: 4/5): Nunn revisits his contract-enforcement framework, suggesting that countries with better enforcement specialize differently and may attract more trade and foreign investment. Culture, gender norms, and the plow hypothesis (Priority: 4/5): He links historical agricultural technology to modern gender roles and female labor-force participation, while noting that development and institutional change can weaken persistence. Methodology in development economics (Priority: 4/5): Nunn criticizes overreliance on RCTs and standardized tests, arguing for more descriptive, field-based, and context-sensitive research that captures local social structure and norms. Personal background and perspective (Priority: 3/5): His low-income upbringing, many early jobs, and Canadian training shaped his focus on mobility, inequality, and intellectual independence.

Key Arguments: Historical factors matter most for explaining long-run income levels, but they do not fully determine outcomes; societies can move in different directions over decades. The slave trade likely damaged trust and institutions by targeting already-dense, well-organized societies, making historical selection into the slave trade endogenous. Persistence is stronger at the level of societies than at the level of geographic locations; people moved, so tracking societies matters more than tracking places. Geography can both help and hurt: fertile coastal areas were attractive, but those same areas were also more exposed to slave raiding, creating omitted-variable problems. Botswana’s relative success is partly explained by small population, ethnic homogeneity, and preserved social structure. The DRC demonstrates that regions can retain strong informal institutions and low crime even when formal state capacity is weak. Christianity and “Weird” Western culture matter historically mostly through family/lineage breakdown and individualism, not because conversion alone guarantees development today. The plow hypothesis helps explain gender norms, but modern development, especially industrialization and rising incomes, can override or weaken those norms. China’s growth and trade fit a contract-enforcement story by specializing in lower-contract-intensive manufacturing, though not necessarily proving strong institutions overall. Development economics should broaden beyond causal identification to include ethnography, focus groups, and better descriptive understanding of local societies.

Data Points: Share of sub-Saharan Africa living in Nigeria: 25% - Nunn cites this to illustrate Nigeria’s unusually large population and the role of fertility and historical selection into slave raiding. Questioned explanatory power of persistence: 5% of variation - Tyler posits a modest persistence effect and asks whether it could still be enough to outperform uninformed investors. PhD/academic concentration: top five schools - Nunn discusses the strong hierarchy in economics and how top talent concentrates in a few U.S. institutions. Female labor force participation in some African countries: 60%-70% - He notes that participation in poorer African countries can exceed Western rates, complicating simple development narratives. Christian population share in many African countries: 97% - He argues that Christianity has spread widely in Africa without deep Western integration. Time in South Korea: 6 months - Nunn says living in South Korea shaped his appreciation of norms around work, education, and collectivism. Personal work history: many jobs across automotive stores, newspapers, factories, ski hills, and tutoring - He uses this background to explain his sensitivity to inequality and mobility barriers.

Pivotal Quotes: "I think we have to really be careful when we're thinking about societies or people or anything, really institutions, policies, because in the cross-section especially... there’s a lot of correlation across observations." — Nathan Nunn: On Morgan Kelly’s critique of persistence regressions and the risk of false positives from spatial correlation. "I think the biggest effect were on these medieval policies of the Catholic Church that broke down lineages and extended family units and created the individual." — Nathan Nunn: On why Christianity mattered to the rise of the West, via institutional and cultural change rather than theology alone. "You basically can't make any mistakes." — Nathan Nunn: On how low-income individuals in the U.S. face severe mobility barriers, informed by his own upbringing.

Implications: The episode suggests development is shaped by deep history, but not trapped by it. Better infrastructure, education, institutions, and research methods can still change outcomes, especially if policymakers understand local social structure rather than relying on one-size-fits-all models.