An elementary-school math teacher silently paces his classroom in a pin-striped stockbroker shirt, his mouth full of braces. All around him, tiny students with pencils in hand struggle over puzzles at their desks. We see the teacher refuse to meet the gaze of one young pupil when he hands back his puzzle, the grid all filled in. “Nervous air is necessary,” the teacher says. “I enjoy nervous air.” The teacher, Tetsuya Miyamoto, is the inventor of KenKen, the puzzle that his students are laboring over. He is also the subject of “Miyamoto and the Machine,” a new documentary about the way the rise of KenKen, an international phenomenon, has been at odds with the meaning its creator hoped to embed in its numerical patterns.
The film’s director, Daniel Sullivan, a high-school instructor, first learned of Miyamoto after his wife started competing in KenKen championships. As in sudoku, the player fills a grid with numbers, and none of the digits in a row or column can repeat, but, within the grid, there are also sets of boxes that must amount to a particular total, whether by addition, subtraction, division, or multiplication. The puzzle’s distributors refer to it as “sudoku on steroids”; in Japanese, “ken” means “wisdom” or “cleverness,” so Miyamoto prefers to translate KenKen, with algebraic panache, as “cleverness squared.”
KenKen puzzles resembling the ones Miyamoto crafts by hand are regularly produced for mass consumption by a piece of software called the Kenerator—but Miyamoto says these computer-generated specimens lack a crucial narrative quality. He intends his mathematical challenges to unfold as stories. Through charming animation, Sullivan reveals how Miyamoto’s feelings about his creations emerged from the story he tells about himself: at fourteen, Miyamoto placed into what he calls “a low-level high school,” got bored, and dropped out. He felt lonely and overwhelmed at the thought that he was just one number in a sea of billions of interchangeable human beings. “If you think of yourself as just one by seven billion,” he says, “it can make you want to die.” The trick, he discovered, was not to quell his nervous energy but to redirect it, in an almost Thoreauvian way. Miyamoto’s philosophy, of life and KenKen, is “not just about nervousness,” Sullivan told me. “It’s also about simplicity, an intense focus.” Miyamoto began to see himself as being at the center of his own story, the better to reimagine the disappointments in his life as the first act in a kind of comeback narrative. (He recognizes the same plot at work in the lives of others, too.) In 1993, after years of cobbling together teaching jobs, he started his own school. Soon he began to craft his first crude puzzles as a way to get third graders to engage with arithmetic. In 2003, he had an Archimedes moment, and KenKen came into being. Three years later, he published his first book of puzzles in Japan. It sold a million and a half copies. KenKen began to appear in the Times in 2009. By 2011, in the aftermath of the Great Sendai earthquake, the game’s addictive power was evident. As aftershocks rattled his classroom, his students—deep inside the grid—did not lift their heads. “This miracle,” he later said, recalling that day, “is something caused by the force of my problems.”
Miyamoto treats each of his puzzles as a life; they are hand molded to tell a story in patterns of math. In 2016, onstage at Google’s offices in New York, in an ill-fitting suit, Miyamoto described the purpose of his pedagogy in ancient Greek terms: the point is to secure eudaimonia, or, as he put it, the “happy life.” After he put the finishing touches on a KenKen puzzle that he made for the Googlers, Miyamoto kissed it: “My baby, how cute you are.” Most people never see his delicate creations. The KenKen puzzles in papers like the Times are produced by the Kenerator. “I feel nothing from this puzzle,” Miyamoto remarks when shown the fruits of the software. “Do you think that, eventually, computers will be able to make a puzzle that is more similar to your puzzles?” Chris Flaherty, one of the film’s producers, asks Miyamoto. The Kenerator would never replace him, the sensei assures us. “Impossible,” he says. “A machine doesn’t have heart.”