The Japanese Kaji, the “godfather of Sudoku”, dies at 69

TOKYO, Aug. 17 (Reuters) – Maki Kaji, a puzzle enthusiast and publisher known as “Godfather of Sudoku” – the digital puzzle played daily by millions of people around the world – has passed away, his company said. He was 69 years old.

A college dropout who worked in a printing house before founding Japan’s first puzzle magazine, Kaji took inspiration from an existing number puzzle to create what he later called “sudoku” – a contraction of Japanese for ” every number must be unique “- sometimes in the mid-1980s.

The logic puzzle challenges people to complete a grid of 9X9 blocks, with nine boxes in each block so that all columns, both vertical and horizontal, contain the numbers 1 through 9 without repeating. The number of figures filled for a grid at the start of the puzzle determines its difficulty.

“Known as the godfather of Sudoku, he was adored by puzzle enthusiasts around the world and we would like to express our gratitude to all of you,” his company, Nikoli, said on its website on Monday.

The cause of death was cancer of the bile ducts.

Sudoku became popular outside of Japan about two decades ago, after foreign newspapers started printing it. Praised as a way to keep one’s mental faculties sharp, it is estimated that over 100 million people around the world regularly attempt the puzzles. A world championship has been organized every year since 2006.

Kaji continued to create and refine puzzles with the help of readers of his quarterly puzzle magazine. He resigned from the management of his company in July due to health problems and died on August 10.

“I am really moved when I see a new puzzle idea that has a lot of potential,” he told the BBC in 2007, adding that the secret to inventing a good puzzle was to simplify the rules.

“It’s like finding treasure. It’s not about whether it’ll make money, it’s purely the excitement of trying to figure it out.”

Reporting by Tim Kelly and Elaine Lies; Editing by Edwina Gibbs

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