The period of the Three Kingdoms, the Jin Dynasty and the Southern and Northern Dynasties was a period of great division in China's history, with constant wars. But during this period, as long as 369 years, from the overall situation, from the mainstream point of view, production is constantly developing. For example, in the early days of the Three Kingdoms, the rulers of Wei, Shu and Wu all attached great importance to economic development. During the Eastern Jin and Southern Dynasties, Jiangnan was widely developed. The reform of Emperor Xiaowen of the Northern Wei Dynasty and the reform of Emperor Wudi of the Northern Zhou Dynasty both restored and developed the northern economy. During this period, some scientists paid attention to economic development, so they made outstanding contributions to science and technology.

First, great mathematicians Liu Hui and Zu Chongzhi:

1. Great mathematician Liu Hui

During the Three Kingdoms period, Liu Hui wrote Notes on Nine Chapters of Arithmetic and Arithmetic of Islands. In Nine Arithmetic Notes, he created many new calculus methods, which are much simpler than the old ones. For example, he first proposed the correct calculation method of pi, which had a great influence on later Zu Chongzhi.

2. The great mathematician Zu Chongzhi.

Zu Chongzhi, whose ancestral home is now Laishui County, Hebei Province. Southern Song Dynasty, Qi Dynasty. His grandfather, Zuchang, was a senior official in charge of construction engineering in Liu, Song and Wang Dynasties. He is very good at mathematics and has a great influence on Zu Chongzhi.

Zu Chongzhi is knowledgeable and versatile. He made great contributions not only in mathematics, but also in astronomical calendar and mechanical manufacturing. For example, he rewrote a calendar called "Daming Calendar", which is more accurate than other calendars according to the data of the running cycle of the sun and the moon. He determined the tropical year, that is, the time between two winter solstice points is 365.38+8+0. Compared with the results of modern astronomical science survey, there is only a gap of 50 seconds, and the relative error of one year is only one in six hundred thousand. He also reformed the jumping method. China used the method of "seven jumps in nineteen years" for a long time, which he thought was not accurate enough. After precise observation of the planet's movement and careful calculation of some mathematical values, it is considered that 144 leap months should be arranged every 39 1 year. After his death, "Da Li Ming" was officially promulgated by the Nanqi regime and has been in use for more than 80 years. He has many inventions in mechanical manufacturing. For example, according to historical records, the compass he made has the functions of "never looking back, never changing" and "not poor, but integrated", but it was later lost. Encouragingly, after three years of tackling key problems, Workers' Village successfully restored Zu Chongzhi's South Compass in 1985 and 12, thus reappearing the cultural heritage lost for thousands of years.

Zu Chongzhi's most important contribution to mathematics is to calculate the exact value of pi and his mathematical monograph Composition.

(3) Pi and composition.

This circle is very important to human production and life. In our daily life, we can often see and use round things. The so-called pi is the ratio of circumference to diameter. This is a fixed constant, which is the value of pi.

Pi is an infinite cycle decimal. The book Parallel Calculation of Weeks compiled at the end of the Western Han Dynasty mentioned that "the diameter is three weeks", that is to say, pi is equal to 3. We call it "ancient rate". The ancient speed was very inaccurate, but it is undoubtedly a great thing that mathematicians in ancient China noticed the calculation of pi so early. Later, Liu Xin in the Western Han Dynasty, Zhang Heng in the Eastern Han Dynasty, Liu Hui in the Three Kingdoms and He Chengtian in Liu Song in the Southern Dynasties all calculated pi. Please have a look at the brief table on page 160 of the textbook. It is worth noting that Liu Hui created a method to find pi, which is called secant, and the value of pi he calculated is called Hui rate. The mathematical achievements of predecessors' research provide valuable reference for Zu Chongzhi to continue to study pi.

Zu Chongzhi recalculated with the secant created by Liu Hui. The calculation tool he uses is a bamboo stick, and it takes more than 130 times to calculate the large number of nine digits, including the root, which is a very arduous task. Zu Chongzhi worked hard and finally worked out the exact value of pi.

Zu Chongzhi is the first mathematician in the world to calculate the value of pi to seven decimal places, and his density is a great discovery in the history of mathematics in the world. A thousand years later, Otto in Germany got the same value, and Antuoni in the Netherlands got the same secrecy rate. Only the Arab mathematician Al-Cassie's calculation surpassed Zu Chongzhi's. Zu Chongzhi is unknown to western mathematicians, so pi is named "Antuoni rate". In 1950s, Kazuo Sanshi, a Japanese mathematician, suggested changing pi to "ancestral rate". Scientists in the former Soviet Union named a crater on the moon Mount Zu Chongzhi. In the corridor of "Exhibition of World Great Scientists" of Moscow University, there is a colored marble statue of Zu Chongzhi. This shows that Zu Chongzhi is respected by people all over the world, and he is the glory and pride of the Chinese nation.

Zu Chongzhi also compiled dozens of papers on mathematics into a book "Composition". The seal script consists of six volumes. It is a must-read for studying mathematics in Sui, Tang and Five Dynasties. In the Tang Dynasty, the state-run school opened the course of "Shu Ming", and "Zhuanshu" was listed as a mathematics textbook, and it was stipulated that it should be completed in four years. It was also used as a teaching material in Japan and Korea in the Middle Ages. This book was the highest achievement in mathematics at that time. Unfortunately, it was abandoned and lost in the Song Dynasty.

Second, with Qi Shu

(1) outstanding agronomist Jia Sixie

Jia Sixie was born in Qingzhou, Shandong Province. He lived in the Northern Wei and Eastern Wei Dynasties. He used to be the magistrate of Levin County (now northwest of Linzi).

Jia Sixie lives in the Yellow River valley where the agricultural economy is developed, which is very beneficial to his agricultural research. In his preface, he said that when he compiled the Book of Qi Yao Min, he had "collected classics, poems and ballads, and asked about the age in order to test it". That is, I have extensively consulted the relevant works of predecessors and collected a large number of folk songs and Yan language; Visit experienced old farmers; Coupled with the author's own personal experience through production practice, this agricultural book was compiled. He called this book the Book of Qi Yaomin, which means "the main way of people's life". As the saying goes, food is the most important thing for the people, and the main source of food is agricultural production. Agriculture-oriented is the main line of Qi Yao Min Shu. In the early days of liberation, the state once recognized Jia Sixie as "the only pure agricultural scientist in ancient China".

(2) The main contents and important contributions of Qi Yaomin's Book.

The Book of Qi Yaomin has nearly 200,000 words and is extremely rich in content. "Starting from a yeoman, I can finally stop eating sugar and finish reading books." The production experience involving agriculture, forestry, animal husbandry and by-product fishing is impressive. In agriculture, Jia Sixie emphasized the importance of soil remediation, fertilization, intensive cultivation, crop selection and crop cultivation. He knows the dialectics of agriculture very well, that is, we often say scientific farming today. For example, he pointed out that we should pay attention to the relationship between time, place and crops. It is pointed out that "the weather, location and people are harmonious, with less efforts and more success." If you do the opposite (against the objective law), you will get nothing if you work hard. "This is what we said today:' Don't lose the farming season' and' adjust measures to local conditions'. For example, he said that there was no garlic in Bingzhou, and the garlic seed taken from Chao Ge turned out to be "Bai Zi garlic", and the garlic petals became very small, while the kohlrabi from other places moved to Bingzhou for planting, and the kohlrabi became as big as a bowl. He said it was caused by different soil conditions. He also emphasized seed selection and advocated ear selection, that is, full grain, pure ear color, single harvest and single release. This is the same as the principle of the optimization method we talked about today. In a word, Jia Sixie systematically summarized the whole process of crop planting, and elaborated in detail from the aspects of land reclamation, seed selection, sowing, cultivation, soil and water conservation, harvesting and storage, which has high practical value.

The Book of Qi Yao Min is the earliest and most complete agricultural book in China, and it is also one of the outstanding works in the world agricultural history. Its main contributions are:

Firstly, the author made a concrete, vivid, systematic and scientific summary of the production practice of the people of all ethnic groups in the north since the Wei and Jin Dynasties, which not only promoted the production at that time, but also played a positive role in the agricultural production of later generations. For example, in 1020, the government of the Northern Song Dynasty carved the Book of Qi Yao Min, which was distributed to "agricultural ambassadors" in various places, and the people also scrambled to copy it. The agricultural books written in past dynasties paid attention to absorbing the essence of Qi Yao Min Shu.

Secondly, some achievements of ancient agricultural books in China are introduced and preserved, such as the agricultural part of Miscellaneous Notes Lv Chunqiu. Another example is the Xi Sheng Shu in the Western Han Dynasty and the Moon Order for Four by Cui Ai in the Eastern Han Dynasty, both of which have been lost for a long time. Due to the citation of Qi Yaomin's Book, some contents have been preserved.

Thirdly, the author collected and recorded many folk songs and agricultural proverbs, which are very precious materials for agricultural experience.

Fourthly, Qi Yao Min Shu also occupies an important position in the history of world biology. For example, the principles of artificial seed selection, artificial hybridization and directional cultivation were initially revealed. British biologist Darwin was inspired by Qi Yao Min Shu.

Thirdly, Li Daoyuan and Notes on Water Classics.

(1) geographer Li Daoyuan

Li Daoyuan was born in Zhuoxian County, Fanyang (now Zhuozhou City, Hebei Province). An outstanding geographer in the Northern Wei Dynasty. Born into an official family. When I was a teenager, I was very eager to learn and read widely. Later, he served as a local official in Henan and other places. He is resolute as an official, tough and famous for being tough and fierce. Therefore, it is still quite disgusting. In 527 AD, he was killed by Xiao Baoyu, the secretariat of Yongzhou, in Yinpan Post Office (now Lintong East, Shaanxi Province). Since he was a teenager, he has been interested in geography and likes sightseeing. His footprints are all over Shandong, Hebei, Shanxi, Henan, Shaanxi, Inner Mongolia, Jiangsu, Anhui, Hubei and other places today. Everywhere you go, you should write down places of interest, pay attention to the topography of water flow, trace back to the water source, and read a lot of ancient geographical works, such as Shan Hai Jing, Yu Gong, Li Zhou Zhi Fang, Geography of Han Shu, Water Mirror, etc. Accumulate rich geographical knowledge. In the process of reading, he found some shortcomings and mistakes in his previous works, one is too simple, the other is the lack of delicate water flow, and the third is self-contradiction. So he made up his mind to write a unique and comprehensive geographical masterpiece in the form of notes, which is the Notes on Water Classics.

(2) Zhu's main contents and important contributions.

Water Mirror is a geographical monograph in the Han and Wei Dynasties. * * * Describe the 137 river, and briefly describe the names of counties and cities where the river passes. This book has more than ten thousand words. Li Daoyuan wrote 40 volumes of Notes on Water Classics, describing 1252 rivers with more than 300,000 words. Annotation is actually an ingenious re-creation. Taking the national waterway as the key link, Shui Jing Zhu describes in detail the mountains, rivers, towns, properties, mineral deposits, customs and historical evolution of the areas where rivers flow. He read a wide range of books, including 437 books that were only quoted in his notes.

The Book of Water Mirrors is still an important work in the study of ancient geography in China, which has important reference value for us to make urban construction planning, build water conservancy, archaeology and engage in historical research today. Therefore, this book is not only valued by geographers, but also by archaeologists, historians, farmland water conservancy scientists and urban construction scientists. At the same time, because of its beautiful writing and literary value, this book is also valued by writers.

Fourth, the new development of medicine

Wang Shuhe and Pulse Classic

Wang Shuhe (201-280) was a doctor in the early Western Jin Dynasty. Mingxi. Dongping (now Dongping, Shandong) people. Cao Wei was appointed as a doctor in the Western Jin Dynasty. Intensive study of medicine and emphasis on pulse science. Zhang Zhongjing, a famous doctor in the Eastern Han Dynasty who had separated at that time, compiled Treatise on Febrile Diseases into Synopsis of the Golden Chamber and Treatise on Febrile Diseases, which preserved most of the contents of this medical document. He also collected the works of the previous generation of doctors on pulse science, combined with his own experience, wrote ten volumes of Pulse Classic, summarized 24 kinds of pulse conditions, and made the ancient pulse science systematic. It is the first extant monograph on pulse in China, which laid the foundation for the diagnosis of pulse in traditional Chinese medicine.

(2) Ge Hong and "Elbow Reserve Emergency Prescription"

Ge Hong (about 283-363) was an alchemist and physician in the Eastern Jin Dynasty. The word Akagawa, also known as Bao Puzi. Jurong was born in Danyang (now Jurong County, Jiangsu Province).

An alchemist is primitive chemistry. Since the Warring States period, there have been many alchemists, and Ge Hong is the most famous one. Bao Puzi, written by him, has made indelible contributions to the development of medicine and chemistry and the invention of gunpowder. Joseph Needham, a contemporary British historian of science, said: "One of the most important roots of the whole chemistry (if not the only one) comes from China." .

Ge Hong has written many medical books, among which Elbow Backup Emergency Prescription has the most practical value. It is rich in content, such as tuberculosis and tsutsugamushi disease, and records the earliest smallpox in China and its prevention and treatment.

(3) Tao Hongjing, a medical scientist

Tao Hongjing (456-536) was a famous physician in the Liang Dynasty. The word is bright, and Huayang lives in seclusion. Danyang Moling (now Nanjing, Jiangsu) people. After seclusion, Qushan (Maoshan). Liang Wudi respected him very much and sent someone to ask him about state affairs. At that time, he was called "Prime Minister in the Mountain".

Tao Hongjing studied medicine deeply and wrote a lot. He collected more than 730 kinds of drugs, and then the standard classification of these drugs was used and enriched 1000 years. He supplemented Ge Hong's Elbow Emergency Prescription and wrote Elbow Back 10 1 Fang to make it more complete.

V. The prevalence of Buddhism and Fan Zhen's "Deism"

(1) The prevalence of Buddhism

At the end of the Western Han Dynasty, Buddhism was introduced into China, which was very popular in the Southern and Northern Dynasties. One of the reasons is that people are dissatisfied with reality and fantasize about getting rid of pain and poverty from religion. As Marx said, "Religion is a feeling of a heartless world". Therefore, many people believe in religion. Second, the ruling class used religious superstitions to anesthetize and fool the people in order to consolidate its rule. They strongly advocate and practice. For example, the prime minister of Qi set a fast period for monks at an early age and personally delivered water and meals to them. Liang Wudi established Buddhism as the state religion. I went to Tongtai Temple three times to be a "temple slave", and then every time his ministers collected a huge sum of one or two hundred million yuan to redeem him. The purpose of their fake play is easy for the discerning eye to see through, but at that time, they did deceive many people. Therefore, during the Northern and Southern Dynasties, the number of monks and nuns was amazing. If you look at the statistics on page 163 of the text, you will know that the prevalence of Buddhism at that time has reached an alarming level.

The construction of Buddhist temples consumes a lot of manpower, material resources and financial resources. For example, in the Northern Wei Dynasty, the statue of Buddha was cast in Tiangong Temple, which cost 65,438+10,000 Jin of copper and 600 Jin of gold. Temple buildings in the Southern Dynasties often have to "exhaust their wealth and keep their affairs high and wide". All these magnificent buildings come from the blood and sweat of working people.

(2) Fan Zhen and the theory of immortals.

Faced with the prevalence of religious superstition, an atheist stood up, and this is Fan Zhen.

Fan Zhen (about 450-5 15) was a native of Wuyin (now northwest of Biyang, Henan Province), an important town in the Southern Dynasties. This word is true. He is poor, but he studies hard and dares to stick to the truth. He lived in the Qi and Liang Dynasties and became an official.

Fan Zhen publicly publicized atheism and criticized the rulers for using Buddhism to cheat, which caused strong dissatisfaction of feudal aristocratic landlords and caused a big debate. The first time was in Qi State. He argued with Wang Xiaoliang Zi of Jingling. The central content of the debate is whether there is such a karma as reincarnation. Fan Zhen expounded his point of view with the famous Debate on Falling Flowers, to the effect that people are born with rich and poor, just like a tree with flowers. Because I saw it, some fell in clean places, and some fell in dirty places. This is accidental, not karma. He argued fiercely, and Xiaoliangzi was speechless. Another man, Wang Yan, said to Fan Zhen in a reproachful tone, "Mr. Fan! You don't know where the god of your ancestors is, which is unfilial. " Fan Zhen replied, "Mr. Wang! Since you know where your ancestors are, why don't you kill yourself and find them? " Later, they used senior officials as bait to make him give up atheism, but Fan Zhen firmly said that I am not a villain who sells theory and takes officials.

The second time happened in the Liang Dynasty, when Liang Wudi personally launched a large-scale siege of Fan Town. 62 dignitaries took part in the siege. They wrote more than 70 articles and besieged Fanzhen. But they couldn't refute Fan Zhen, and finally they took political persecution and exiled him to Guangzhou to die.

Between the two debates, Fan Zhen systematically expounded his atheistic views and wrote the famous article "Theology". The main arguments are: body and spirit are interrelated and interdependent, and spirit cannot exist without body; Secondly, the body comes first, then the spirit, just like the relationship between the blade and sharpness. Without a blade, sharpness disappears. Its purpose is to prove that the preaching of immortality of the soul is groundless. According to historical records, "when this theory came out, both the ruling and the opposition were surprised", which shocked the whole society.

Fan Zhen's "Deism" fundamentally denied the cheating and fooling of the feudal rulers on the people, and politically shook the spiritual fortress of the ruling class. Therefore, Fan is really another materialist thinker after Xun Kuang in the Warring States and Zhang Heng in the Eastern Han Dynasty. Deism occupies an important position in the history of China's ancient thoughts and is a valuable cultural heritage.