There has been a lot of concern in recent years about the end of privacy. As we will see in the next two chapters, there is reason for such fears; the development of improved technologies for surveillance and data processing does indeed threaten our ability to restrict other people's access to information about us. But a third and less familiar technology is working in precisely the opposite direction. If the arguments of this chapter are correct we will soon be experiencing in part of our lives – an increasingly important part – a level of privacy that human beings have never known before. It is a level of privacy that not only scares the FBI and the National Security Agency, two organizations whose routine business involves prying into other people's secrets; it sometimes even scares me.

We start with an old problem: how to communicate with someone without letting other people know what you are saying. There are a number of familiar solutions. If you are worried about eavesdroppers, check under the eaves before saying things you do not want the neighbors to hear. To be safer still, hold your private conversation in the middle of a large, open field or a boat in the middle of a lake. The fish are not interested and nobody else can hear.

That approach no longer works. Even the middle of a lake is within range of a shotgun mike.