Prologue: The conspiracy effect : why smart people believe blatantly wrong things for apparently rational reasons Why people believe conspiracy theories. Conspiracies and conspiracy theories : the difference in thinking and the difference it makes ; A brief history of conspiracy theories and conspiracists : toward a science of conspiracism ; Proxy and tribal conspiracism : how conspiratorial beliefs are reinforced as truths ; Constructive conspiracism : paranoia, pessimism, and the evolutionary origins of conspiracy cognition ; A case study in conspiracism : the sovereign citizens conspiracy theory How to determine which conspiracy theories are real. The conspiracy detection kit : how to tell if a conspiracy theory is true or false ; Truthers and birthers : the 9/11 and Obama conspiracy theories ; JFK blown away : the mother of all conspiracy theories ; Real conspiracies : what if they really are out to get you? ; The deadliest conspiracy in history : the trigger of World War I and how conspiracies really work ; Real and imagined enemies : conspiracies in reality and in our imaginations Talking to conspiracists and rebuilding trust in truth. How to talk to conspiracy theorists : engaging with people with whom we disagree ; How to rebuild trust in truth : reason, rationality, and empiricism in reality-based communities Coda: What people believe about conspiracy theories and why : results of the Skeptic Research Center survey