GREAT INVESTIGATIONS
Typhoid Mary: How a Sanitary Engineer Tracked an Asymptomatic Carrier
George Soper investigated a typhoid outbreak by reverse-engineering the residence and employment history of every affected family. The pattern that emerged: a single Irish cook, Mary Mallon, who had been moving from household to household leaving outbreaks behind her. She had no symptoms herself.
What this story trains
The investigative move that cracked the case was pivoting from "what is making people sick" to "who has been adjacent to every sick group". Pattern recognition at the population level.
Pattern RecognitionLogical Reasoning
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