I found the coolest list the other day (wow, that sounds so cheesy!), it is a site called Science Heroes. There is one page in particular that had me floored: the general gist of it most important contributions to humanity via lives saved. (I know, I know, lists suck, but this one doesn’t!) The answers might surprise you.
Fritz Haber takes the list with 2.72 billion lives saved. How did he do it? Synthetic fertilizer. If I had to take a guess before seeing such a list, I would’ve guessed Edward Jenner, who came up with the concept of vaccination when he noticed that milk maids who had been exposed to Cowpox did not succumb to Smallpox. Jenner, it turns out, is number 5 with an estimated 530 million people saved. Haber solved, it turns out, a century-long problem that had vexed humanity’s growth: how to fix nitrogen from the atmosphere to be used in farming. It is safe to say that industrialized farming exists in a long chain of cause-and-effects because of this man. His successful discovery of this problem (later industrialized by Carl Bosch, #2 on the list) is what earns him the top spot of the greatest scientists list. The number of people that he saved is hard to understand at an emotional level: 2,720,000,000. Almost 40% of the population of Earth today! Or, 2.72% of all the humans that have ever lived in Earth’s history (100 billion people). Second, as I alluded to earlier, on the list, is Carl Bosch who duly shares in this discovery by mass-producing the process; something which Haber was not able to do. (It’s not all roses, however: Faber was instrumental in the chemical warfare that become the defining feature of WW1 on the German side, so there’s that.)