Back in 145 AD, a successful doctor named Galen rocked the medical world and developed procedures that would be used for 1500 years. This trend continued until a man named William Harvey stepped in with an alternative hypothesis.

Harvey was a trailblazer, fighting against centuries of established scientific dogma virtually by himself. As our friends at the World Science Festival put it, "He ruffled a lot of feathers, but eventually became a major influence on modern medicine."

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