The meaning of a message, says William Mitchell, depends on the context of its reception. "Shouting 'fire' in a crowded theater produces a dramatically different effect from barking the same word to a squad of soldiers with guns," he observes. In Placing Words, Mitchell looks at the ways in which urban spaces and places provide settings for communication and at how they conduct complex flows of information through the twenty-first century city.

Cities participate in the production of meaning by providing places populated with objects for words to refer to. Inscriptions on...