By a curious confusion, many modern critics have passed from the proposition that a masterpiece may be unpopular to the other proposition that unless it is unpopular it cannot be a masterpiece.
The best that Gauss has given us was likewise an exclusive production. If he had not created his geometry of surfaces, which served Riemann as a basis, it is scarcely conceivable that anyone else would have discovered it. I do not hesitate to confess that to a certain extent a similar pleasure may be found by absorbing ourselves in questions of pure geometry.
Practice is absolutely necessary. You may sit down and listen to me by the hour every day, but if you do not practice, you will not get one step further. It all depends on practice.