Cities and ethics: An essay for Jane Jacobs

This tribute to Jane Jacobs connects her seminal work on cities with her ne wer focus on ethical systems. I present a model and evidence suggesting tha t cross-community mobility in cities makes it difficult to enforce strict e thical standards. Just as Jacobs' argues that cities permit technological i nnovations, cities appear to permit ethical innovations. Finally following Jacobs' distinction between mercantile ethical systems and warrior (or guar dian) ethical systems, I present a model where cities become centers for me rcantile ethics. Current evidence shows that urban residents are more pro-m oney and residents of small towns are more likely to support the army.