Years before a computer could force a draw in American checkers, my dad and I stumbled on the answer.
We had two checker options in our home, red or black, which is traditional in American checkers. But when choosing my color, only one option was acceptable: red. Sure, red was my favorite color, but it also goes first in American checkers. Whoever makes the first move has a slightly higher chance of winning. With that winning edge on my side 99% of the time, I was a checker-driving force you didn’t want to mess with.
I was obsessed with checkers, and I didn’t want to lose. So, when I forced a draw in February 1982 during a checkers game with my dad, I was less than happy. In checkers, the player who prevents his opponent from making a forward move is the winner. While I was a very good checkers player, this was not planned. The picture shows me smiling, but I remember being upset about being stuck because it didn’t feel like I had won the game. The draw broke the routine of a checkers game, where I was supposed to claim victory after capturing all of my opponent’s pieces.
Checking the routine
Checkers games went like this: I would get an old tin tea can that contained the plastic checkers and our brown and black particle wood checkerboard from the shelf at the bottom of the corner cupboard in our living room. Then, I would boil a kettle of water to make tea—a beverage so fascinating to me that I once let my car get towed for a ¼ pound of it—that I would sip from a porcelain Garfield mug while playing. As the loose leaves were brewing in a McCormick teapot, I marched from the kitchen to my dad’s office and begged him until he agreed to stop working and play with me. If my grandfather was in town, I’d corner him; he was always good for at least a couple of games. Always sure they would say yes, I had another mug waiting on the kitchen table next to mine, the teapot, and the board.
Then came the draw. More than 25 years before data scientists figured out how to force a draw in American checkers, I was sitting in front of the solution. In fact, ChatGPT interjected this comment while I was doing research for this blog:
“If you’re writing about your own draw from the 1980s, that’s actually pretty cool—because back then, most players didn’t know the kinds of techniques that force a draw, and engines didn’t exist yet to teach them. So even a single draw could’ve meant you both played a near-perfect game!”
Indeed, I didn’t know any techniques to force the draw. After all, I was only 5.
Checking the math
A draw in a game of American checkers played by people is exceptionally rare. Casual players might find themselves in a draw only 5-15% of the time. Professional players end about half of their games in a draw, but most computers using AI models will usually end their games in a draw. And why not? In 2007, checkers became one of the few board games to be weakly solved—meaning that, with a perfect set of 10 plays from both players, the game will always end in a draw. Data scientists at the University of Alberta developed the AI program Chinook in 1989, the same year the World Wide Web went live, to get the answer. Using a decision tree algorithm known as a game tree, the statisticians trained Chinook with billions of calculations. It was considered a breakthrough in both artificial intelligence and game theory. Anyone can play Chinook online.
A decision tree algorithm courtesy Automation.com
Checkers has been a favorite for AI research since the 1950s. Even Alan Turing, considered the founder of AI, tried to solve checkers. Because of its relatively simple rules and many possible positions, the game was ripe for testing how computers can learn to evaluate positions, make decisions, and improve over time with iterations.
Today, data scientists still have not strongly solved checkers. When a game like American checkers is strongly solved, players can know the solution to win or come to draw from any position on the board regardless of previous moves. Strongly solving checkers is not practical. It takes a ton of computer processing power. A modern PC gaming system with 64–256 GB RAM and an SSD disk read speed of about 5 GB/s would take more than six years just to read the full dataset to solve the problem.
Checking the past
American checkers has ancient roots, with games like Alquerque played in the Middle East thousands of years ago. The modern version was developed in 12th-century France. It evolved into several variants, including the version most Americans know today.
Alquerque, Life of Riley, CC BY-SA 4.0
American checkers—also called English draughts—is played on an 8 x 8 board using just the dark squares. Each player starts with 12 pieces and moves diagonally forward one square at a time. When a piece is catacorner to an opponent and no other piece protects it, the opponent must capture the piece by jumping it. When a piece reaches the far side of the board, it becomes a king and is crowned with a captured piece. A king can move forward and backward, still just one square at a time.
Compared to chess, checkers is relatively simple. This is why data scientists developed Chinook to play checkers instead. The AI model has faced off against Marion Tinsley and other legendary human players. It was the first AI model to win a human world championship title in any board game.
Checking the future
Could I have claimed a world championship as a checkers child prodigy? I’ll never know. My dad was my No. 1 competitor while my grandfather Saxton was a solid runner-up. The elder Saxtons enjoyed being my favorite opponents despite my tantrums when I lost. Of course, I didn’t win every game, but I always had a blast. Sometimes, my worthy opponents even got a kick out of it when I would make a silly move and lose one of my pieces or worse, a king.
While I never learned if I could claim global victory, I haven’t lost my touch at checkers. A friend plays a Facebook-based checkers game with me nearly every day. I don’t win all the digital games, but it’s still fun 43 years after I accidentally forced my dad into a draw and inadvertently “solved” the game of checkers.
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