Why are some governments more effective managers of resources - people, places and finances - and others less effective? This question is at the center of understanding political and economic development. Yet, established theory that explains how individual cognitive differences and sociological forces mutually explain government effectiveness is lacking. To bridge this knowledge gap we articulate the Functional Intelligences Proposition (FIP): The individual level attributes of general intelligence and social intelligence serve unique information processing functions and have a positive and independent effect on the ability of individuals, acting in concert, to govern resources. To begin to evaluate the FIP, we study the effects of general intelligence, social intelligence and social infrastructure (prosocial norms & trust) on how effectively US states govern. We find that measures of general intelligence (estimated by IQ) and social intelligence (social-cognitive theory of mind - ToM - estimated by agreeableness) have a positive and independent effect on the effectiveness of governance. The FIP provides an interdisciplinary explanation for the effectiveness of governance and, ultimately, development.