The twentieth century has been hailed as the age of networks. But Neil Ferguson argues in The Square and the Tower that networks have always been with us from the structure of the brain to the food chain, from the family tree to Freemasonry. Throughout history, while hierarchical systems in the tall towers claimed to rule us, the real power lay below, in the networks, in the town square. And because networks tend to innovate and renew, revolutionary ideas can spread through them in a viral, contagious way. Just because conspiracy theorists fantasize about these networks doesn't mean they aren't real