It is not always by plugging away at a difficulty and sticking to it that one overcomes it; often it is by working on the one next to it. Some things and some people have to be approached obliquely, at an angle. РAndr̩ Gide, Journals, 26 October 1924

The mark of highest originality lies in the ability to develop a familiar idea so fruitfully that it would seem no one else would ever have discovered so much to be hidden in it. – Goethe