"A broader view of platform governance uses insights borrowed from the practices of nation-states as modeled by constitutional law scholar Lawrence Lessig. In Lessig's formulation, systems of control involve four main sets of tools: laws, norms, architecture, and markets.20 A familiar example can be used to clarify these four kinds of tools. Suppose leaders of a particular ecosystem want to reduce the harmful effects of smoking. Laws could be passed to ban cigarette sales to minors or forbid smoking in public spaces. Norms--informal codes of behavior shaped by culture--could be applied by using social pressure or advertising to stigmatize smoking and make it appear "uncool." Architecture could be used to develop physical designs that reduce the impact of smoking--for example, air filters that clean the air, or smokeless devices that substitute for cigarettes. And market mechanisms could be used by taxing tobacco products or subsidizing "quit smoking" programs. Historically, those who want to control social behavior--including platform managers--have employed all four of these tools."