20. Where to from here?
This kind of rather highflown speculation is an essential part of my job. Without some capacity for it I could not have qualified as a Mobile, and I received formal training in it on Hain, where they dignify it with the title of Farfetching.
Ursula K. LeGuin, The Left Hand of Darkness (1969)
This final chapter has two purposes. A few topics not considered earlier are discussed briefly; usually there is a central problem which has served as a focus for research. Then there is a list of assorted problems in other areas, and some recommended reading for further investigation of some of the main subdivisions of combinatorics.
20.1. Computational complexity
This topic belongs to theoretical computer science; but many of the ...