What can we do to avert catastrophe and avoid extinction? The political class won't save us. According to Roger Hallam, real change comes from ordinary people breaking the law. In Common Sense for the 21st Century, Hallam explains why mass disruption, mass arrests, and mass sacrifice are necessary and details how to carry out acts of civil disobedience effectively, respectfully and non-violently. He bypasses contemporary political theory and takes his inspiration from Thomas Paine, the pragmatic 18th century revolutionary whose pamphlet Common Sense sparked the American Revolution.