Like many fans of cyberspace, Lessig acknowledges the important differences between the physical realm of social interaction and the ethereal world of cyberspace interaction. As a New Yorker cartoon pointed out, on the Internet nobody knows if you are a dog. It is easy to dismiss online activity as a kind of fictional realm, but Lessig insists that life on the Internet is in key respects just as real as any other kind of life. The consequences of things said and actions taken in cyberspace might not be exactly the same as they are in the physical realm, but they are real nonetheless. Every person, including those working in cyberspace, is in the physical realm.
All physical realms are subject to sovereign interests, such as the local government's jurisdiction.
Those who enter cyberspace remain in that physical realm, but they are also in an altogether different realm where different rules might apply. People in cyberspace can pretend to be what they are not, sometimes with serious consequences for those with whom they interact. A person residing physically in a state that forbids gambling can engage in cyber-gambling hosted by servers in a jurisdiction where gambling is legal. Similarly, a person in cyberspace can view pornography provided by a server in a liberal jurisdiction while physically residing in a jurisdiction where pornography is strictly prohibited. When these two realms are governed by different sovereigns, conflicts of authority will arise.