Shanghai. New York. Tehran. Tokyo. Today, dozens of cities worldwide are each home to many millions of people. But those masses of humanity might not exist in such tight quarters if not for John Snow. (No, not that Jon Snow. This John Snow.) Snow was a 19th-century English doctor who’s credited with proving that cholera, […]
View more »
Sign up for TED email updates
New talks released daily. Be the first to know!