We have only recently begun to recognize it, yet it exists at every level of our lived experience. It is fast becoming clear that our lives revolve around the powers of emergence. An ant colony behaves with an intelligence no particular ant possesses; a brain is conscious although no particular brain cell is; a city develops districts and neighbourhoods no planner could impose. In each case, complex problems are solved by a profusion of relatively simple elements. Order arrives from the bottom up, not top down. Such systems display emergent behaviour: the movement from low-level rules to higher-level sophistication. Media, technology and cultural critic Steven Johnson ranges from computer games that simulate living ecology to the guild system of 12th-century Florence; from the initial cell division that marks the very beginning of life to software that lets you listen to the sound of your own brain. The connections between these systems are not the links of poetic metaphor. Everywhere the same laws are obeyed, the same swarm logic is at work. Johnson unearths a secret history of decentralized thinking, looking at those like Adam Smith, Friedrich Engels and Alan Turing who contributed to the study of self-organization long before this became a recognized science. But most of all Johnson pursues emergence in the present, investigating the software that will soon allow artificial emergence to transform our media, bringing sweeping cultural and political change in its wake. This compelling and revelatory book is rich with insights into that future. Emergence allows us to witness the exhilarating arrival and sudden ascendancy of a potent new idea.