3 ms·

Japan is not in the Occident. By the way, the "solution" cited in the article is "divide the blue radius by 3", with no proof, so there's no superior mathemati

by lupire 2y ago

Japan is not in the Occident. By the way, the "solution" cited in the article is "divide the blue radius by 3", with no proof, so there's no superior mathematical prowess on display in this example. The article says "Fukagawa Hidetoshi, a wasan researcher and former high school mathematics teacher who received his PhD from the Bulgarian Academy of Sciences, explains the problem and its solution as follows." but there is no explanation of the problem or it's solution. Also, the article incorrectly transcribed the problem from the photograph into the computer diagram, and the original woodcut doesn't even show an eclipse (so maybe the Edo Japanese wasn't describing an ellipse at all), and the problem doesn't make a whole lot of sense (the red and white circles are completely irrelevant to the problem) so the whole thing is suspect overall. It's cool that Edo people were drawing pictures and writing about geometry, though. Finally, the article title is a clickbait lie.

wizzwizz4 2y ago
> Japan is not in the Occident. And I don't know the Japanese education system. I know that the Chinese high-school-equivalent mathematics curriculum is slightly different to what I've seen from English and French and German (and American) schools, so the current Japanese system might be different as well. (Though, the Chinese system also has the issues I've described.) > By the way, the "solution" cited in the article is "divide the blue radius by 3", with no proof, Many results in mathematics are published without proof, and are still considered significant. Heck, Euclid's Elements, which is known for its generally rigorous attitude, omits full proofs of several results. > Also, the article incorrectly transcribed the problem from the photograph into the computer diagram, Arguable. I'd say they just chose different values for the free parameters. > and the original woodcut doesn't even show an eclipse You're right. But it does show a sketched ellipse – at least, that's similar to how I drew them before I became familiar with computer-rendered examples. The insistence on geometry diagrams being to-scale is a fairly recent phenomenon: generally, owing to the difficulty of producing to-scale diagrams, the attitude has been "don't trust the diagram", and the focus when creating a diagram is making sure that intersection points are obvious. Look into the modern tradition of curve sketching. > and the problem doesn't make a whole lot of sense (the red and white circles are completely irrelevant to the problem) They're not irrelevant: they constrain the relative positions of everything as the size and position of the blue circle varies. They're not relevant when the blue circle is at its maximum, but that's part of solving the problem. > Finally, the article title is a clickbait lie. The subtitle, “A Historical Look at Japan’s “Wasan” Math”, is much better.

by lupire 2y ago

wizzwizz4 2y ago

> Japan is not in the Occident. And I don't know the Japanese education system. I know that the Chinese high-school-equivalent mathematics curriculum is slightly different to what I've seen from English and French and German (and American) schools, so the current Japanese system might be different as well. (Though, the Chinese system also has the issues I've described.) > By the way, the "solution" cited in the article is "divide the blue radius by 3", with no proof, Many results in mathematics are published without proof, and are still considered significant. Heck, Euclid's Elements, which is known for its generally rigorous attitude, omits full proofs of several results. > Also, the article incorrectly transcribed the problem from the photograph into the computer diagram, Arguable. I'd say they just chose different values for the free parameters. > and the original woodcut doesn't even show an eclipse You're right. But it does show a sketched ellipse – at least, that's similar to how I drew them before I became familiar with computer-rendered examples. The insistence on geometry diagrams being to-scale is a fairly recent phenomenon: generally, owing to the difficulty of producing to-scale diagrams, the attitude has been "don't trust the diagram", and the focus when creating a diagram is making sure that intersection points are obvious. Look into the modern tradition of curve sketching. > and the problem doesn't make a whole lot of sense (the red and white circles are completely irrelevant to the problem) They're not irrelevant: they constrain the relative positions of everything as the size and position of the blue circle varies. They're not relevant when the blue circle is at its maximum, but that's part of solving the problem. > Finally, the article title is a clickbait lie. The subtitle, “A Historical Look at Japan’s “Wasan” Math”, is much better.