This story has popped up on Reddit today. Four british players held AlphaZero to a draw with white by exploiting the fact that it only plays the “best” moves, which apparently leads to the Berlin. What a surprise, or not? Well, that’s exactly what this website is all about. White has at least a draw and he can force it in all major openings! With black it’s indeed a different story. They managed to hold in the King’s Indian where AlphaZero chose a line that was popularized by Sokolov in a match against Van Foreest in 2016.

The final position is a fortress, which is shows the second weakness of chess engines. Nice coincidence for a 2-game match.

Not only that engines only play the highest ranked move, which leads to horizon problems, they do not understand that a variation leads to a fortress early enough either, which is also a horizon problem. Humans on the other hand know what they are aiming for, so they can work their way backwards. Engines just make strong moves, while humans can use imagination to their advantage. For imagination to become a strength it requires some sort of knowledge though. If you don’t know what a fortress is, it doesn’t help to imagine the position where black is roughly a pawn down.

For the record: I can hold AlphaZero to a draw in Tic-Tac-Toe.