How Checkers Was Solved
It's good, really, that this article focussed on Tinsley.  I saw a talk by Schaeffer about ten years ago, just as he was finishing up solving checkers, and it was an astonishingly depressing talk.  He invested his whole life—decades—as I recall his marriage failed partially as a result of his obsession with this—on what, in the end, was a lookup table.  There was a lot of neat engineering he had to do along the way (storage, parallel work) but that's not what he cared about: he cared that he had solved checkers.  Were there any insights about patterns that could be induced, maybe to teach humans how to do analysis or to learn some interesting mathematical fact about the graph structure of the board?  No—you just see what the board state is, and look it up in the database to tell you the next move.  I can't even tell you how demotivational this speech was.