Frederick Banting grew up isolated on a farm in Essa, Ontario, struggling with school and failing out of a general arts program before petitioning his way into medicine. As a World War I trauma surgeon he earned the Military Cross, once operating for sixteen hours after shrapnel severed a blood vessel in his own arm. That battlefield bias for decisive action shaped everything that followed.

Prepping a lecture on the pancreas in October 1920, he conceived a way to isolate insulin by tying off the pancreatic duct. Working with Charles Best, John Macleod, and James Collip at the University of Toronto, and later sourcing fetal calf pancreases, the team produced insulin that saved fourteen-year-old Leonard Thompson in 1922. Banting shared his 1923 Nobel Prize money with Best, exposed exploitation in the Arctic, helped design an anti-G suit, and  ...