around 1500, the Swiss physician Paracelsus noticed that Galenic [medical] treatments did not actually make patients better, and that some treatments—like mercury for syphilis—worked even though they made no sense within humoral theory. Paracelsus began to advocate listening to evidence rather than deferring to the authority of the long dead: “The patients are your textbook, the sickbed is your study.” In 1527, he even staged a public burning of Galen’s work. His vision took centuries to take hold—nearly 300 years later, George Washington died after an aggressive bloodletting—because people are more inclined to believe neat and simple stories like Galen’s than to confront messy and complex reality.
Paracelsus started with what worked and followed that to why. First-principles thinkers start with a hypothesized “why” and then insist it works, regardless of the results. Are our modern entrepreneurship thinkers more like Paracelsus, driven by evidence? Or more like Galen, sustained by the elegance of their own story? In the name of science, let’s look at the evidence.