I think there's something in the middle. One does not need to learn everything, of course, and it pays to learn many new key concepts. Groundbreaking concepts h

I think there's something in the middle. One does not need to learn everything, of course, and it pays to learn many new key concepts. Groundbreaking concepts help us identify new problems and find simple solutions. Another advantage of learning key concepts is that we get to connect all those concepts, and connections beget breakthroughs. As for what concepts to learn first, I think Feynman's method helps: "You have to keep a dozen of your favorite problems constantly present in your mind, although by and large they will lay in a dormant state. Every time you hear or read a new trick or a new result, test it against each of your twelve problems to see whether it helps. Every once in a while there will be a hit, and people will say: 'How did he do it? He must be a genius!'"