Twitter is mostly useless, and everybody on it usually sounds stupid, but as I pretty much have to force myself occasionally to wade through the Twitter accounts of my colleagues in order to see (amidst many very groanworthy jokes, pointless memes, and uninformed political opinions that are exactly like everyone else's uninformed political opinions but stated in a much more lecturing and indignant tone) what people are reading and recommending -- since I have to do this anyway, I have to take time to enjoy the rare great tweet I come across. This tweet was the one that made today's Twitter-skimming bearable.