In which the curious nature and varied consequences of madness are examined as a potent and indispensable force behind great political upheavals, philosophical innovations, and religious fervours, likened to vapours rising through the faculties of the brain in diverse and unpredictable ways. It is proposed that, rather than being a mere malady, madness might be fruitfully harnessed by judicious employment and timely adaptation, transforming supposed lunatics into useful actors within the commonwealth’s grand design.