Confined in Bedlam in 1797 as an incurable lunatic, James Tilly Matthews is one of the most bizarre case studies in the annals of psychiatry. Often cited as the first thorough case study of what we would today call paranoid schizophrenia, Matthews drew intricate diagrams of the "influencing machine" that he believed to be reading and controlling his mind. But his case was even stranger than his doctors realized: many of the incredible conspiracies in which he claimed to be involved were entirely real. A Visionary Madness traces the story of antiwar advocate James Tilly Matthews through the political and social upheaval of the late eighteenth century, providing a vivid account of the unraveling of Matthews's mind, a snapshot of late eighteenth-century psychiatry, and its relevance to current narratives of madness, conspiracy theories, mind control, and political manipulation. Digging deep into historical records and primary sources, author Mike Jay carefully untangles truth from delusion, providing evidence that Matthews was a political prisoner as much as a madman: he had been working as a double agent in the French Revolution and was privy to political secrets the British government feared he might expose. In the process, Jay illuminates the murky revolutionary politics of the 1790s and situates Matthews' visionary madness within the wider cultural upheavals of a world on the brink of modernity. The details of Matthews' treatment in Bedlam reveals the birth-pangs of early psychiatry and its struggle to free its patients from the harsh regimes of the eighteenth-century madhouse. A fascinating and fast-paced narrative history, A Visionary Madness raises profound questions about the nature of madness and the birth of the modern world.