Song Ling'er didn't know what etiquette was, and after dinner, she pulled Wang Yuan to her boudoir and looked at the maid Wang Yangming bought.

"Are you testing me?" Wang Yuan joked.

Song Ling'er didn't speak, just stood there and stared, as if Wang Yuan had said the wrong thing.

Wang Yuan immediately changed the topic: "Didn't you say last time that I want to teach you a new algorithm?" Let's go, let's go to the study. ”

Song Ling'er was even more unhappy, and followed Wang Yuan sullenly.

Wang Yangming was engaged in academic research in the study, continuing to improve his theory of mind, and he didn't bother to talk to the two when he saw them come in.

Wang Yuan took up the pen and wrote down ten numbers from 0 to 9, so that Song Linger was slowly familiarized.

"It's easy to write, but it's a little inconvenient to remember." Song Linger's attention quickly turned to numbers.

Wang Yuan smiled: "Write it a few more times and remember it." ”

Unconsciously, Song Ling'er had already practiced several pages of papyrus, and basically mastered Arabic numerals, but it was impossible to say whether she would be confused when she woke up tomorrow.

Suddenly, Uncle Wang's voice came from behind: "What country is your number?" 0, 1, and 9 are a bit like the Tessie numbers. ”

"Sir, do you know Tessie numbers too?" Wang Yuan was a little surprised.

Wang Yangming immediately picked up the brush and wrote the ancient version of Arabic numerals. 0, 1, and 9 are exactly the same, 2 is written sideways, 3 is written sideways with a tail, 4 and 5 are completely unknown symbols, 6 is similar to the letter y, 7 is the same as the letter V, and 8 is the letter V written backwards.

Wang Yuan looked at those ancient numbers in a daze and asked, "This is the Taixi number?" ”

Wang Yangming said with a smile: "I have seen people write in Yuyao, and it is indeed more convenient to write hundreds or thousands of large numbers. ”

Wang Yuan feels awkward no matter how he looks at it, for example, "17", and the Arabic numerals at this time are written as "1V". "26" looks like "Ny", and N has to be written from left to right, and the right side is dragged very long.

The left-to-right writing of individual letters did not correspond to Chinese and European writing habits, so it was later improved by Europeans into modern writing.

Wang Yangming wrote it again according to Wang Yuan's figures, and immediately praised: "Your writing method is more convenient and simple." ”

Wang Yuan also wrote symbols such as addition, subtraction, multiplication, and division, and taught Song Linger to learn the four operations.

Song Ling'er quickly became happy: "This is much easier to learn than "Nine Chapters of Arithmetic". ”

Nonsense, the first question of "Nine Chapters of Arithmetic" is to find the area, which is of course more difficult than addition, subtraction, multiplication and division.

The "Island Arithmetic" and the "Arithmetic of the Five Classics" are more difficult, the former studies triangulation problems, and the latter can make beginners stunned.

Wang Yangming observed for a while and felt that this method was more intuitive, and it was much more convenient than using words and calculations to express it. And the larger the number, the more complex the calculation, the easier it is. He couldn't help asking, "Ruoxu, when did you master this exotic arithmetic?" ”

Wang Yuan said nonsense: "When I took the test in Yunnan Township, I was taught by an elder. The Tessie numbers he wrote were similar to those written by Mr. Taixi, and I found it a little inconvenient, so I improved them. ”

Wang Yangming thought for a while and said, "You can write a book of "New Calculations", and I will make a preface, or you can extend it. ”

"This won't be criticized by Shilin, right?" Wang Yuan asked.

Wang Yangming said with a smile: "It's not so much criticism, at most it is regarded as a small road." ”

"Then I'll write it out." Wang Yuan instantly lost his worries.

The literati of the Ming Dynasty were very fond of research, and the specific content was varied, among which arithmetic was one of the main directions.

In another twenty years, Daming will give birth to a super genius, who has made remarkable achievements in mathematics, literature, calendar, dance, music, musical instruments, etc., this person is Zhu Zaiyu, the king of Xiao Zheng.

Wang Yuan continued to teach Song Ling'er arithmetic, and Wang Yangming also watched from the sidelines, raising some doubts from time to time, but soon drew inferences and bypassed.

At this time, it was already dark, and Wang Yuan couldn't go back through the curfew, so he simply lived in Wang Yangming's house.

In the following days, Wang Yuan wrote arithmetic manuscripts during the day, and went to teach Song Ling'er after work, but he also lived a very chic and comfortable life.

In less than half a month, Wang Yuan finished writing the manuscript of the "New Arithmetic Sutra", which is nothing more than numbers, formulas, four operations, mixed operations, one-dimensional equations and fraction conversion, all of which are some elementary school mathematics content.

And it's certainly not as detailed and verbose as primary school textbooks, just write down each knowledge point clearly, and then give an example question to get it. Compressing more than half of the knowledge points of primary school mathematics into a thin thirty or forty pages of manuscript paper requires researchers to comprehend it themselves.

After asking Wang Yangming to make a preface, Wang Yuan took it to find a printing shop.

The owner of the printing workshop shook his head again and again: "Mr. Wang, your book can't be printed with movable type, and you have to spend energy to make engraving." And I'm afraid the market is not too good, and I can't sell a few copies after engraving. If you really want to publish a book, all the expenses must be borne by Mr. Wang. ”

It's just that I publish books at my own expense, and I can't sell them.

In fact, arithmetic books were very popular in the Ming Dynasty, as early as the era of Zhu Yuanzhang, Hangzhou Qindetang engraved a set of "New Journal Yang Hui Algorithm", which has been reprinted many times in the country in the past 100 years. Including the "Nine Chapters of Arithmetic", these arithmetic books are second only to the imperial examination textbooks, literary and historical classics, poetry and calligraphy, and discourse books.

The problem is, what kind of Arabic numerals did Wang Yuan make the owner of the printing shop look at him very much.

Wang Yuan didn't pay for the engraving himself, and he had to worry about the sales when he printed it, so he directly took the manuscript and dedicated it to Zhu Houzhao.

"Your Majesty, this is the sutra written by the minister recently." Wang Yuan smiled and handed it over.

Zhu Houzhao said: "I didn't expect Wang Erlang to be proficient in arithmetic, I must have a good life." ”

Zhu Houzhao opened the manuscript and saw all kinds of strange symbols, and instantly felt like he was pitted.

What the heck?

Wang Yuan pointed to Wang Yangming's preface and said: "This is a Taixi number, which is not easy to write and identify, so the minister has made some improvements. ”

Zhu Houzhao frowned and asked, "What is the use of these things?" ”

Wang Yuan replied, "It can make it easier for beginners to learn arithmetic. These are just the basics, and the ministers will also write more in-depth calculations, which are useful in terms of acres, taxes, transportation, grain and grass, calendars, etc. ”

Zhu Houzhao likes all kinds of new things, and it is recorded in the "History of the Ming Dynasty": "Franc machine ...... It made the firefighter Yasan because Jiang Bin served the emperor, and the emperor learned his language as a play. ”

Well, Zhengde had a Portuguese translator by his side, and the emperor often followed the translator to learn Portuguese. This is the thirteenth year of Zhengde.

Zhu Houzhao not only speaks Portuguese, but also proficient in Sanskrit, and his history records that he "knows all Buddhist scriptures and Sanskrit". In addition, Zhu Houzhao also studied music and drama, and personally composed "Killing Array Music".

This emperor is absolutely smart, but he has crooked the skill tree.

There is no need for Wang Yuan to teach by the side, Zhu Houzhao corresponds to the Chinese and numbers in the manuscript, and he learns it there. And the more he learned, the more energetic he became, and after he became familiar with numbers and various symbols, he read dozens of pages of manuscripts in half a day.

"It's all very simple stuff, I've learned it since I was a teenager, is there anything harder?" The Emperor asked.

Wang Yuan was quite speechless and said, "Yes." ”

So, Wang Yuan taught the emperor decimal points and decimal places in the leopard room, and then taught the geometry content of primary and junior high schools.

Zhu Houzhao is particularly fond of geometry, scratching his ears and cheeks at various figures, and after solving the answer, he is inexplicably excited.

"This is a good law for the benefit of the country!"

After solving a trapezoidal problem, Zhu Houzhao pointed to the topic and said: "This can be used to calculate the size of the embankment, which is more convenient than the current algorithm, and officials of the Ministry of Industry should learn it." ”

Wang Yuan patted his ass and said, "Your Majesty Shengming." ”

Zhu Houzhao threw the manuscript to the eunuch and said, "Order the celebrant to engrave it immediately, and when Wang Erlang finishes writing the "Principles of Geometry", he will print it together and hand it over to the Huitong Pavilion for distribution. ”

The Master of Ceremonies has jurisdiction over the Hanjing Factory, the Daojing Factory, and the Fanjing Factory, which are specifically responsible for engraving books, which are collectively referred to as "Jingchang Books". For example, during the Jiajing period, the celebrant published the "Romance of the Three Kingdoms", which is the earliest official engraving of the "Romance of the Three Kingdoms".

is also a famous work, the treatment of "Water Margin" is much more miserable, it has been banned by the imperial court several times, and it has revived after each ban.

The celebrant was dedicated to serving the emperor, and the ministers could not control it.

However, once the book is distributed nationwide, some people will inevitably accuse Wang Yuan of not doing his job.

Moreover, the official will also impeach Wang Yuan, accusing Wang Yuan of guiding the emperor to delve into arithmetic and the way, after all, Zhu Houzhao's learning of Portuguese is despised by officials.