While economists continue to debate whether individual economic policies, such as those contained in Willliamsons (1993) Washington Consensus, can help to spur growth in developing countries, this paper demonstrates that it is groups of policies that are more critical for growth. Policy...

I show that in a conventional Ramsey model, between one-fourth and one- half of income differences across countries can be explained by a single factor: The steady-state effect of large, persistent differences in national average IQ on worker productivity. These differences in cognitive...