» Sangaku was the Sudoku of the 17th century, complex math problems based on principles even a child could understand. Because the Japanese cut themselves off from the West, they didn't learn about Calculus when it was invented. They developed Sangaku to solve similar problems. "Some of the tablets feature solutions provided by 12-year-olds. But that doesn’t mean they were easy. Today’s high school geometry problems tend to require only five or six lines to solve, whereas the old problems often demand pages and pages of work. Sangaku were more like math Olympics problems, or the sort of thing your teacher might have put on the wall for extra credit." Tony Rothman, Princeton physics lecturer.
rebecca's pocket
.: August 2006 --> Sangaku was Sudoku for the 17th century
Sangaku was Sudoku for the 17th century
[ 08.15.06 ]
While the Japanese could not learn of the development of Calculus in Europe, geometry in Europe was pretty much dormant for the first part of the Edu period. They may have come with novel problems but not with any novel method for solving geometric problems. Thus the argument that puts both Calculus and geometric sangaku under the same umbrella is necessarily flawed.
Also, the number of surviving tablets is so small relative to the population of Japan and the length of the seclusion period as to attach a big question mark to the popularity of sangaku. It's very unlikely that a broad slice of the population ever cared for the geometric problem solving.
Regardless of the degree of fascination with the Japanese history and calture that one may feel, the fact is that there are just a couple of sources (Tony Rothman's article and Dan Pedoe's book, both associated with the same Japanese authority, H. Fukagawa) from which the rest of the newsmakers drew their inspiration. Earlier sources that are completely disregarded by the modern crowd were much more balanced in their judgement.