I think any plausible theory of growth must start with Adam Smith's and   
later Jane Jacob's observation that growth happens in cities. Moreover, as   
Jacobs further observes, growth happens by import substitution under   
conditions of active competition and trade. Finally, as any development   
economist can tell us, growth proceeds faster in more egalitarian societies   
with relatively low levels of corruption.  
  
Has anyone built models that incorporate at least some of these facts?  
  
Polly Cleveland