"The history of mathematics is a history of horrendously difficult problems being solved by young people too ignorant to know that they were impossible." -Freeman Dyson
(In fairness, I only discovered that because I tracked down the original source to try finding out which specific "young people" Dyson had in mind. He seems to imply Abram Samoilovitch Besicovitch as one example; I can put forward George Dantzig as another. But other than them...)
Another month, another rationality quotes thread. The rules are: