This one is by the great Indian development economist, Debraj Ray. There is a ton of great material in this, so go read it please, posthaste! I can’t resist quoting the penultimate paragraph, with some great tidbits about Arrow’s famous quirks (and genius):
There are many stories about Ken Arrow. Some are semi-apocryphal. Some we can vouch for. For instance, I have seen him nod off during talks (including one that I gave) and then wake up to ask a remarkable question. And he did flip pencils in seminars, and I have seen him on at least one occasion attend a talk with his bicycle helmet on. Once Doug Bernheim and I, convinced that a speaker was wrong, paid no further attention to the seminar and tried to construct a counterexample together. Arrow somehow knew that that was what we were up to, because after the seminar he walked into Doug’s office (where we were still at it), wrote the required example on the board, did a little jig and walked away — complete with bicycle helmet. But one story possibly is apocryphal, and yet fully sums up the Ken Arrow that I was so fortunate to know. Arrow was in class, teaching. He was speaking fast, running as he always did with his thoughts. Students were frantically taking notes as the disembodied sentences emerged. And then, suddenly: “Stop, stop! That’s all wrong!” As the students frantically began to erase their jottings, he continued: “No, no, not what I said, what I was going to say.”