Look at Mother Teresa. She spent her whole life being holy. She didn't benefit anyone in any real sense. She didn't work on stopping disease, helping poverty, doing anything that would relieve the condition of her countrymen. She just went around the city, picked up dying people, and took care of them while they died. It was a good thing, no doubt, but it meant no betterment, no progress, no help, no relief from pain. She longed to be holy. She wanted to be a saint. Now she's a saint.
Salk isn't a saint. But he did more for the human race than Mother Teresa did. He didn't long to be holy, which meant having faith, not asking questions, doing something unpleasant without thought or complaint. He longed to do good, which meant finding things out, asking hard questions, and thinking hard, deep thoughts. Goodness and holiness are two different things, unfortunately.