Talent hits a target no one else can hit; Genius hits a target no one else can see. - Arthur Schopenhauer

"There are two kinds of geniuses, the 'ordinary' and the 'magicians,' " wrote the mathematician Mark Kac. "An ordinary genius is a fellow that you and I would be just as good as, if we were only many times better. There is no mystery as to how his mind works. Once we understand what they have done, we feel certain that we, too, could have done it. It is different with the magicians. They are, to use mathematical jargon, in the orthogonal complement of where we are and the working of their minds is for all intents and purposes incomprehensible. Even after we understand what they have done, the process by which they have done it is completely dark.