As on TV, as in print, Paul Mason's enthusiasm and curiosity are infectious. Newsnight's economics editor sees in the 2008 crash the seeds for a new social order. Why is it happening now? Ultimately, he says, the answer lies in three big social changes: "In the demographics of revolt, in technology and in human behaviour itself."

Mason takes us on a journey of the global indignados, from the Spanish graduate without a job to the Egyptian revolutionary, to the venue where, in terms of this book, it all began: a squat in Bloomsbury. On the basis of that discussion, Mason penned a blog giving 20 reasons "why it's kicking off everywhere". That post, by his own admission, went viral and led the author to expand on his ideas.

Adapting a rich vein of leftwing revolutionary thought for the wired generation, Mason argues passionately that the old rules have been broken. He relocates Marx as an advocate of personal freedom, whose analysis would not be out of place in the social media age: collective action meets individual rights meets egalitarianism.

Mason is a half-full sort of guy. I'm far more sceptical. For every optimistic assertion that he makes, such as: "People know more than they used to", I posit the counterpoint. Yes, but has all that information actually made us more able to engineer change or influence outcomes? Indeed, little that's happened in the five years since the banks sent to us to our knees suggests to me that we've learned the lessons. Only a few weeks ago at Davos, the financial titans were exhorting one another to stop wittering on about the sins of the past and get back to making money.

Often people living in the midst of epochal change struggle to identify its importance. Of Mason's 20 strictures, perhaps this is most telling: "People have a better understanding of power." They can see its abuse, economically and politically, in a way they could not before. Will that frustration and anger be channelled into concrete change? That is another question.

John Kampfner is author of Freedom for Sale and Blair's Wars