When I asked Dr. Jonas Salk, inventor of the polio vaccine, why he chose a career in medicine, he said it came from a deep concern for human suffering — and a childhood dream of serving humanity. As a boy, he wanted to follow his hero, Abraham Lincoln, into law and politics to fight for justice. But in college, he realized he could help humanity on an even larger scale through medical research. It’s such a powerful reminder: our deepest purpose stays the same, but the way we scale our impact can