The "father of Sudoku", Maki Kaji, is dead

Enlarge image

Maki Kaji in September 2012

Photo:

YASUYOSHI CHIBA / AFP

The number puzzle game has long since become a popular sport for the brain worldwide, he designed it in such a way that it is easy to solve for anyone who does not want to think too much: Maki Kaji is dead. As the Nikoli publishing house he founded announced, the Japanese died on August 10th after a long period of cancer.

"Mr. Kaji was known as the father of Sudoku and was loved by puzzle fans around the world," the publisher said.

The family man was 69 years old.

The principle of Sudoku, a kind of numerical crossword puzzle, was invented in the 18th century by the Swiss mathematician Leonhard Euler.

However, Kaji was instrumental in making the puzzle famous.

A college dropout who worked in a print shop before founding Japan's first puzzle magazine in 1983, Kaji took clues from an existing number puzzle in order to develop what he later called "Sudoku" in the mid-1980s.

An abbreviation of the Japanese sentence "Suji wa dokushin ni kagiru", roughly: "Each number must be individual".

Numbers were popular outside of Japan after the British Times, among others, began to print it on the advice of a returnee from Japan.

A world championship has been held annually since 2006.

With the help of the readers of his quarterly puzzle magazine, Kaji developed and refined numerous puzzles until he resigned from the management of his publisher in July for health reasons.

"I'm really touched when I see a new idea for a puzzle that has a lot of potential," he told the BBC in 2007.

The secret to inventing a good puzzle is to make the rules simple: “It's like a treasure hunt.

It's not about whether you can make money with it, but rather that it's exciting to solve it. "

sak / dpa / Reuters / AP