The history for the most part is hierarchical: it has to do with emperors, presidents, prime ministers, and generals; with states, armies, and companies; with orders from above. Even the history "from below" usually concerns trade unions and labor parties. But is this happening because hierarchical institutions create the archives on which historians rely? Are we thus losing sight of the informal, much less studied social networks that are the true sources of power and forces of change?

The 21st century was hailed as the Age of Networks. However, as Neil Ferguson argues here, networks have always been among us, from the structure of the brain to the food chain, from the family tree to freemasonry. Throughout history, hierarchies established in tall towers claimed to govern, but often the real power was found below, in the town square. Because networks have a tendency to innovate. And revolutionary ideas are dispersed through networks. The fact that conspiracy theorists like to fantasize about such networks does not mean they do not exist.

From the cults of ancient Rome to the dynasties of the Renaissance, from the founding fathers to Facebook, the book tells the rise, fall, and rise again of networks, showing how network theory - concepts such as clustering, degrees of separation, weak ties, and transitional phases - is changing the way we understand the past and the present.

If "The Evolution of Money" put Wall Street in historical perspective, "The Square and the Tower" does the same for Silicon Valley. It also makes a bold prediction about the hierarchies that will withstand this new wave of network disruption - and those that will fall.