Suugaku – What is Japanese mathematics like?

The Japanese have a writing system different from the Western one and also various cultural issues. Many end up wondering how mathematics works in Japan, thinking about this we are writing this article. Mathematics in Japanese is called Suugaku (数学) and there are two types of it in Japanese, the Western one is called yousan (洋算) and the Japanese way is wasan (和算).

Japanese also has its own numbers using ideograms, but they also use Western numbers. The big truth is that Japanese numbers and counting are much more logical and systematic than Western ones. We recommend that you already have knowledge about Japanese numbers so you don’t get lost in Japanese mathematics.

Wasan – The mathematical origin in Japan

Wasan was developed in Japan during the Edo period (1603-1867), the term wasan literally means Japanese (和) calculation (算). It was coined in the 1870s but unfortunately is in decline due to the influence of Western mathematics. There are not many differences between Japanese and Western mathematics, it is just something historical, but in practice mathematics is always the same.

Among the history of mathematics in Japan, one of the greatest pride inventions is the soroban or Japanese abacus. There is also Sangaku, which are mathematical puzzles that were placed in temples and shrines to challenge people. Seki Kowa was the most influential Japanese mathematician before contact with the West. He discovered solutions to solve systems of linear equations, eliminating dependent variables.

The difference between Japanese mathematics and Western mathematics is that they did not apply much of their research and discoveries to other areas besides geometry. Thus, they ended up adopting Western mathematics.

Multiplication trick

The Japanese have a method to perform multiplications more easily. It consists of drawing sets of parallel lines that represent each digit of the first number to be multiplied. Then draw sets of parallels, perpendicular to the first sets of parallels, corresponding to each digit of the second number (the multiplier). Look at the figure and count the number of intersections of the parallel lines:

I can’t explain well in words, but each alignment of the parallel lines represents a digit of the final result. And just like in traditional multiplication, it is better to obtain the result by counting the numbers starting from the back. See one of the examples in the figure written in calculations to see how this method is simpler than the traditional one: 23 x 12 = (2×10 + 3)(1×10 + 2) = 2x1x10² + [2x2x10 + 3x1x10] + 3×2 = 276

How do the Japanese do calculations?

Mathematics in Japan is done the same way as in the West. Even Japanese children are introduced to the Arabic numbers we use, but they also use ideograms. One of the few things that changes is the pronunciation in Japanese; if you know English, it is easy that they use many variations of English.

We use the same mathematical signs from Western mathematics in Japanese. However, Japanese also uses the verbs to add, multiply… along with Japanese ideograms. We use tasu (足す) as the verb for addition, to sum or more. Example: 7 + 3 = 10 / nana tasu san wa juu desu (七足す三は十です). In Japanese, we use desu (です) to say equal (＝) such as: (X + Y = 50) in Japanese we would say X + Y は 50 です。 And we use the word ten to refer to the (. and,) of decimal numbers. Example: 3,5 (san ten go).

In Japanese, we can also use the English variation of the 4 mathematical operations (kangenjojo – 加減乗除). They are the same as in Portuguese. Below we will see a list of their pronunciation:

The verbs for adding, subtracting, multiplying, and dividing followed by zan (算) are used to say addition, subtraction, division, etc. 引き算 (hikizan), 掛け算 (kakezan), 割り算 (warizan),

Mathematical vocabulary in Japanese

Of course, this is just the basics about mathematics in Japanese. For you to delve deeper, we will leave a vocabulary table for you to conduct your research: