How we can invent—but not predict—the future of cities. We cannot predict future cities, but we can invent them. Cities are largely unpredictable because they are complex systems that are more like organisms than machines. Neither the laws of economics nor the laws of mechanics apply; cities are the product of countless individual and collective decisions that do not conform to any grand plan. They are the product of our inventions; they evolve. In Inventing Future Cities , Michael Batty explores what we need to understand about cities in order to invent their future. Batty outlines certain themes—principles—that apply to all cities. He investigates not the invention of artifacts but inventive processes. Today form is becoming ever more divorced from function; information networks now shape the traditional functions of cities as places of exchange and innovation. By the end of this century, most of the world's population will live in cities, large or small, sometimes contiguous, and always connected; in an urbanized world, it will be increasingly difficult to define a city by its physical boundaries. Batty discusses the coming great transition from a world with few cities to a world of all cities; argues that future cities will be defined as clusters in a hierarchy; describes the future “high-frequency,” real-time streaming city; considers urban sprawl and urban renewal; and maps the waves of technological change, which grow ever more intense and lead to continuous innovation—an unending process of creative destruction out of which future cities will emerge.

A proposal for a new way to understand cities and their design not as artifacts but as systems composed of flows and networks. In The New Science of Cities , Michael Batty suggests that to understand cities we must view them not simply as places in space but as systems of networks and flows. To understand space, he argues, we must understand flows, and to understand flows, we must understand networks—the relations between objects that compose the system of the city. Drawing on the complexity sciences, social physics, urban economics, transportation theory, regional science, and urban geography, and building on his own previous work, Batty introduces theories and methods that reveal the deep structure of how cities function. Batty presents the foundations of a new science of cities, defining flows and their networks and introducing tools that can be applied to understanding different aspects of city structure. He examines the size of cities, their internal order, the transport routes that define them, and the locations that fix these networks. He introduces methods of simulation that range from simple stochastic models to bottom-up evolutionary models to aggregate land-use transportation models. Then, using largely the same tools, he presents design and decision-making models that predict interactions and flows in future cities. These networks emphasize a notion with relevance for future research and planning: that design of cities is collective action.