Marion Tinsley

Marion Franklin Tinsley (February 3, 1927 – April 3, 1995) was an American mathematician and checkers player. He is widely considered the greatest checkers player ever. Tinsley was world champion from 1955–1958 and 1975–1991 and never lost a world championship match. He lost only seven games (two to the Chinook computer program, one in a simultaneous exhibition) from 1950 until his death in 1995. He withdrew from championship play between 1958–1975, relinquishing the title during that time. Derek Oldbury, sometimes considered the second-best player of all time, thought Tinsley was "to checkers what Leonardo da Vinci was to science, what Michelangelo was to art and what Beethoven was to music." Tinsley was the son of a school teacher and a farmer who became a sheriff. He had a sister and "felt unloved" by his parents.

His 1951–1995 tournament record, excluding the Chinook games:

Chinook games Tinsley retired from championship play in 1991. In August 1992, he defeated the Chinook computer program 4–2 (with 33 draws) in a match. Chinook had placed second at the U.S. Nationals in 1990 after Tinsley, which usually qualifies one to compete for the World Championships. However, the American Checkers Federation and the English Draughts Association refused to allow a computer to play for the title. Unable to appeal their decision, Tinsley resigned his title as World Champion and immediately indicated his desire to play against Chinook. The unofficial yet highly publicized match was quickly organized, and Tinsley won.

In one game from their match in 1990, Chinook, playing with white pieces, made a mistake on the tenth move. Tinsley remarked, "You're going to regret that." Chinook resigned after move 36, only 26 moves later. The lead programmer Jonathan Schaeffer looked back into the database and discovered that Tinsley picked the only strategy that could have defeated Chinook from that point and Tinsley was able to see the win 64 moves into the future.

The ACF and the EDA were placed in the awkward position of naming a new world champion, a title which would be worthless as long as Tinsley was alive. The ACF granted Tinsley the title of World Champion Emeritus as a solution.

In August 1994, a second match with Chinook was organized, but Tinsley withdrew after only six games (all draws) for health reasons. Don Lafferty, rated the number two player in the world, replaced Tinsley and fought Chinook to a drawn match at game 20. Tinsley was diagnosed with pancreatic cancer a week after the match, and died seven months later.

Death Tinsley died in Humble, Texas, on April 3, 1995, at the age of 68. He lived in Conyers, Georgia, but was visiting his sister in Texas when he died of cancer. He was survived by a twin sister, Mary Clark, who lived in Humble, Texas, and by two brothers, Ed, of Sarasota, Fla., and Joe, of Thornville, Ohio.

Television appearances In 1957, Tinsley appeared as a guest challenger on the television game show To Tell the Truth.