Unbridled passions threatened nineteenth-century America, a vulnerable young nation already feeling beset by foreigners, corruption, and disease. Purifying crusaders like Hamilton College philosophy professor and Presbyterian minister John W. Mears mobilized to fight every sin and carnal lure, from liquor to free love. In Upstate New York's famed Oneida Community, Mears encountered his stiffest challenge. Oneida's founder and patriarch, John Humphrey...