I love this story so much. This The Atlantic article telling the full tale is a favorite of mine [1]
It's hard to overstate how incredibly dominant Tinsley was. In his entire career, he never lost a match, and only ever lost 7 games (two to Chinook). That is out of maybe tens of thousands of games. He was a mathematician by training and taught at a historically black university. He was also deeply religious and a lay minister at a black church. He famously described the difference between chess and checkers like this: “Chess is like looking out over a vast open ocean; checkers is like looking into a bottomless well.”
I could just quote the entire article, but I'll just leave it at this passage:
> The two men sat in his office and began the matches, Schaeffer moving for Chinook and entering changes in the game into the system. The first nine games were all draws. In the tenth game, Chinook was cruising along, searching 16 to 17 moves deep into the future. And it made a move where it thought it had a small advantage. “Tinsley immediately said, ‘You’re gonna regret that.’” Schaeffer said. “And at the time, I was thinking, what the heck does he know, what could possibly go wrong?” But, in fact, from that point forward, Tinsley began to pull ahead...
> The computer scientist became fixated on that moment. After the match, he ran simulations to examine what had gone wrong. And he discovered that, in fact, from that move to the end of the game, if both sides played perfectly, he would lose every time. But what he discovered next blew his mind. To see that, a computer or a human would have to look 64 moves ahead.
Tinsley was simply one of the most remarkable human minds of the 20th century. I'm happy he finally got a challenger that was worthy of him (as no other humans could even come close), but it also seems fitting that he was never officially defeated in a real checkers match. Rest in peace.
If you like that you might like Jonathan Schaeffer's (the creator of Chinook) book "One Jump Ahead" in which he discusses Chinook and Tinsley in great detail.
It's hard to overstate how incredibly dominant Tinsley was. In his entire career, he never lost a match, and only ever lost 7 games (two to Chinook). That is out of maybe tens of thousands of games. He was a mathematician by training and taught at a historically black university. He was also deeply religious and a lay minister at a black church. He famously described the difference between chess and checkers like this: “Chess is like looking out over a vast open ocean; checkers is like looking into a bottomless well.”
I could just quote the entire article, but I'll just leave it at this passage:
> The two men sat in his office and began the matches, Schaeffer moving for Chinook and entering changes in the game into the system. The first nine games were all draws. In the tenth game, Chinook was cruising along, searching 16 to 17 moves deep into the future. And it made a move where it thought it had a small advantage. “Tinsley immediately said, ‘You’re gonna regret that.’” Schaeffer said. “And at the time, I was thinking, what the heck does he know, what could possibly go wrong?” But, in fact, from that point forward, Tinsley began to pull ahead...
> The computer scientist became fixated on that moment. After the match, he ran simulations to examine what had gone wrong. And he discovered that, in fact, from that move to the end of the game, if both sides played perfectly, he would lose every time. But what he discovered next blew his mind. To see that, a computer or a human would have to look 64 moves ahead.
Tinsley was simply one of the most remarkable human minds of the 20th century. I'm happy he finally got a challenger that was worthy of him (as no other humans could even come close), but it also seems fitting that he was never officially defeated in a real checkers match. Rest in peace.
[1]: https://www.theatlantic.com/technology/archive/2017/07/mario...