Ask HN: Who are the 'fathers' of discoveries for whom we can be thankful today?

Discoveries, inventions, ideas, concepts... John McCarthy, Marvin Minsky, Linus Torvalds, Newton, Einstein, Carl Linnaeus, (insert others)... Is this a worthwhile exercise? I hope people can share insights about whom they list. They can be anyone, but famous scientists and the like are easy to think of off the top of the head.