Two things come to mind here. First is the urban myth (well, I don't know if it happened or not) of the student arriving late to class just as homework assignm

Two things come to mind here. First is the urban myth (well, I don't know if it happened or not) of the student arriving late to class just as homework assignments are being handed out, and the student diligently works at the problems though the last one is very hard, and hands them in. The teacher approaches him later and is shocked that he was able to solve the last question which was actually an unsolved problem in the field. The student arrived after that information was shared with the class, and hence simply thought he had to solve it and so did. Second the phrase "if you don't know how it breaks, you don't know how it works".