The history of science and technology is an important part of the history of human civilization, which also incorporates the high wisdom and hard work of the ancient Chinese people.However, until half a century ago, the world's academic circles were still shrouded in the fog of scientific "Eurocentrism", completely ignoring the scientific and technological achievements of ancient China.This is extremely unfair.Of course, this has something to do with Westerners' lack of understanding of Chinese culture and our own lack of research on the history of Chinese science and technology at that time.Beginning in the 1940s, British science historian Joseph Needham and others conducted a systematic investigation of ancient Chinese science and technology, absorbed the research results of Chinese science and technology historians, and wrote the book "History of Science and Technology in China".Through this masterpiece, Needham and others showed the world the great achievements of science and technology accumulated in ancient China for thousands of years, and its great contribution to the development of world civilization. "Without this contribution, we would not have The whole development of Western Civilization".

To understand what are the great scientific and technological achievements in ancient China, the large number of ancient Chinese scientific and technological classics are undoubtedly a huge treasure house worthy of careful exploration.According to statistics, there are more than 10,000 works on ancient Chinese medicine, thousands of works on mathematics, and nearly 400 works on agriculture.These science and technology classics not only record the achievements of ancient my country in various scientific fields such as astronomy, mathematics, agronomy, geography, chemistry, physics, and engineering technology, but also leave behind many experiences and lessons from previous scientific research.

The development of scientific and technological works is closely related to the development of production and science and technology.my country is one of the main birthplaces of early human civilization in the world; it is one of the earliest areas in the world to use fire, invent bows and arrows, pottery, agriculture and animal husbandry, astronomy and medicine; especially our ancestors invented silkworm breeding very early And silk weaving technology, has been known as the country of silk in history.However, before the generation of writing, people's scientific knowledge and technology were passed on in the form of "oral teaching", which was greatly restricted in the exchange and preservation of scientific and technological knowledge.After the creation of writing, scientific knowledge and technology can be recorded in writing, breaking through the limitations of time and space in dissemination, and playing a vital role in the development of science and technology.In our country, numeral symbols have been found in the simple characters carved on pottery during the Yangshao Culture period; while in the mature oracle bone inscriptions of the Shang Dynasty, more information about medicine, geography, astronomy, agriculture, etc. are recorded. Scientific and technological knowledge; As for the bronze inscriptions of the Zhou Dynasty, as well as early documents such as "Book of Changes", "Shangshu", etc., scientific and technological materials can be seen everywhere, reflecting the level of science and technology at that time.However, before the Spring and Autumn Period and the Warring States Period, literature and classics were managed by full-time personnel such as shamans, historians, and divination, and ordinary people could not easily see them, and even fewer were handed down.Therefore, we don't know whether there were scientific and technological monographs at that time, and what kind of scientific and technological monographs there were.The scientific and technological classics we see now began from the Spring and Autumn Period and the Warring States Period.

The Spring and Autumn and Warring States period was an era of great social change. Changes in production relations and the application of science and technology greatly improved production, which in turn promoted the rapid development of science and technology.At that time, a class of intellectuals called "shi" appeared in the society, which broke the old government's monopoly on culture, and formed a vivid situation of ideological liberation and academic freedom of "a hundred schools of thought contend".In academic debates, the ancient theories of qi, yin and yang, and five elements have also been enriched and perfected, providing a useful tool for systematically sorting out scientific and technological data.Due to the above-mentioned favorable conditions, a large number of scientific and technical works began to emerge during this period.In terms of astronomy, almost all the princes at that time had people in charge of astronomical observation of the sun, moon, planets and stars, and wrote books and books, accumulating a wealth of astronomical data.Among them, the famous "Astronomy and Astrology" by Gan De of Qi and "Astronomy" by Shi Shen of Wei, collectively known as "Gan and Shi Xingjing" (already lost).The book measures the length of the rendezvous period of Venus and Jupiter, the stellar periods of Mars and Jupiter, etc., indicating that the astronomical research at that time has moved towards the direction of quantification.In the late Spring and Autumn period, the four-point calendar was generally adopted by the vassal states. It took the length of the return year as 3651/4 days, and adopted the seven leap weeks in 19 years as the leap week, which marked that our calendar had entered a relatively mature period.In terms of mathematics, the world's leading decimal value system of notation and the traditional calculation system were continuously improved during this period. The records in the pre-Qin literature prove that four arithmetic operations and fractional operations were used at that time. The mathematics education he received is called "Nine Numbers".It is generally believed that at least in the late Warring States period, my country had produced mathematical works, but they have been lost.In medicine, a group of famous medical scientists such as Bian Que and Yihe emerged at that time. Some of them have begun to organize medical knowledge in combination with qi, yin and yang and other thought systems. The Eleven Meridian Moxibustion Classic and the Fifty-two Disease Prescriptions are the earliest known meridian monographs and prescriptions, while the famous "Huangdi Neijing" focuses on basic theories such as human anatomy, physiology, pathology, etiology, and diagnosis. , and acupuncture, meridian, health care and other aspects of content, laid the foundation of the motherland's medical theory system.In terms of agriculture, fine traditions such as intensive farming in agricultural production began to take shape at this time, and it was possible to achieve five crops in four years and two crops in a year. "Shangnong", "Rendi", "Biantu", and "Shenshi" in "Lu Shi Chunqiu" are the oldest agricultural treatises in my country. Agricultural production techniques and principles.During the Spring and Autumn Period and the Warring States Period, due to the development of production, commerce flourished, and transportation developed accordingly.People's field of vision has expanded, and a large amount of geographical data has been accumulated, which has promoted the development of geography.Taking the mountain as the key link, it describes the location of the mountain and its hydrology, flora and fauna, minerals, myths and legends, etc. "Yu Gong" describes the mountains and water systems in most parts of our country, and divides the whole country into Kyushu, which has the germination of the idea of ​​natural geographical division and regional comparison.During this period, the handicraft industry also developed rapidly, with meticulous division of labor and exquisite technology. The excavation of the famous Zenghouyi chime bell and a batch of ancient vehicles reflected the superb technical level at that time.At that time, the two famous works "Mo Jing" and "Kao Gong Ji" complemented each other, made theoretical summaries and abstract generalizations of people's rich experience in production, and achieved fruitful results in the research of optics, mechanics, and geometry. In particular, it shows the importance of initial experimental science for deepening people's understanding.

The Qin and Han Dynasties were an important period in the history of the development of science and technology in ancient my country.The unification of the country, the policies of "rest and rejuvenation" and the lifting of ideological imprisonment in the early Han Dynasty all created conditions for the development of production and the improvement of science and technology.The emergence of iron smelting technology and textile machinery, the invention of papermaking, and the construction of large-scale civil engineering projects such as the Great Wall reflect the maturity of production technology at that time; while the emergence of some classic scientific works shows that ancient Chinese science and technology have formed their own unique characteristics. system.In terms of astronomy, the three traditional theories of Gaitian, Huntian, and Xuanye have been summarized and clearly expressed. Zhang Heng's "Lingxian" and "The Illustrated Notes of the Armillary Sphere" are based on the armillary sphere theory, and systematically discuss the thoughts about the creation and evolution of the universe, which is why the armillary celestial theory occupies a dominant position in ancient astronomy. Lay the groundwork.The calendar at this time has basically matured and has the main content of the calendar of later generations.From "Taichu Calendar" to "Qianxiang Calendar", a set of relatively scientific methods for calculating the movement of the five stars, the movement of the sun and the moon, and the cycle of eclipses have been established. The principle that the month of solar terms) is a leap month is still in use today.In astronomical calculations, a large number of mathematical operations were used, which also reflected the level of mathematics at that time to a certain extent.Representing the highest level of mathematics at that time was "Nine Chapters on Arithmetic", which summarized the mathematical knowledge accumulated in ancient my country in the form of a collection of examples, and included a considerable part of the content of arithmetic, algebra and geometry in elementary mathematics. His own system has become a classic of mathematical works.In terms of agriculture, the crop rotation system based on the Warring States period, the basic principles of general crop cultivation and the technical measures of intensive cultivation to increase the yield per unit area have been established at this time.According to "Hanshu Yiwenzhi", there were nine agricultural books at that time with as many as 114 volumes. Its representative "Book of Fansheng" summarized six basic links in agricultural production (timely cultivation, land use and improvement, fertilization, etc.) , Moisture conservation (Shang Shang), timely intertillage and weeding, timely harvest) theoretical and technical issues, and the cultivation methods of more than ten kinds of crops.Medicine was also further developed in the Qin and Han Dynasties. It is the earliest surviving book on herbal medicine, which laid the foundation for later generations of herbal medicine; It is the originator of TCM clinical syndrome differentiation and treatment.In terms of geography, the maps unearthed from the Mawangdui Han Tomb reflect the people's rich geographical knowledge and high surveying and mapping technology at that time, and the term "geography" appeared for the first time in "Hanshu Geographical Records", and opened up a history A new field of geographic research.In addition, alchemy also made significant progress at this time.Wei Boyang conducted theoretical explorations based on the experience of his predecessors in alchemy. His "Book of Changes Can Tong Qi" is the earliest theoretical work on alchemy in China.

During the Wei, Jin, Southern and Northern Dynasties, our country was in a state of confrontation between the North and the South and the establishment of different regimes for a long time.The change of regime weakened the cultural dictatorship, so various ideas became active; the unprecedented integration of nationalities and the development of southern and remote areas promoted the exchange of production technology and scientific knowledge; therefore, during this period, the ancient Chinese scientific and technological system It has been further enriched and improved, and has made major breakthroughs in some aspects.Due to the continuous improvement of astronomical instruments, astronomical observation data have become increasingly rich and accurate, especially major discoveries and innovations such as precession, unevenness of the sun and five-star motion, which directly affect the reform of the calendar of later generations.At that time, the calendar improved a number of astronomical constants. For the first time, the "Yuanshi Calendar" of Zhao (bandit owed) [fei bandit] in Beiliang broke the old law of 19 years and seven leaps, and proposed a new leap week of 221 leap months in 600 years.Later, Zu Chongzhi proposed the leap week of 144 leap months in 391 years in the "Da Ming Calendar", which was more precise.Zu Chongzhi calculated that the length of the return year is 365.2428148 days, which is only 46 seconds away from today's calculated value.The Wei, Jin, Southern and Northern Dynasties also set off the first climax of ancient mathematics research, with Zhao Shuang's "Zhou Bi Zhu", Liu Hui's "Nine Chapters of Arithmetic" and "Sea Island Mathematical Classics", as well as "Sun Tzu Mathematical Classics", "Xiahouyang Suanjing", "Zhang Qiujian Suanjing", Zu Chongzhi's "Zishu", Zhen Luan's "Five Cao Suanjing", "Five Classics Suanshu", "Shushu Jiyi" and other mathematical works.These mathematical works have greatly enriched the ancient Chinese mathematical system represented by "Nine Chapters of Arithmetic".For example, Liu Hui not only gave theoretical demonstrations for most of the algorithms in "Nine Chapters of Math", but also created several new algorithms such as "cutting circles" in "Jiu Zhang Shu Shu Zhu"; According to the calculated pi ratio in Shushu: 3.1415926<π<3.1415927, this value is ahead of the world for thousands of years.In terms of agriculture, Jia Sixie's "Qi Min Yao Shu" is the earliest complete agricultural book in my country. The book systematically summarizes my country's agricultural history before the 6th century AD from the aspects of crop cultivation, farming techniques and agricultural tools, animal husbandry and veterinary medicine, and food processing. Agricultural production and agricultural science and technology in the northern drylands had a great influence on the agronomy of later generations.During this period, medicine has developed in an all-round way, and the achievements in acupuncture and moxibustion and pulse science are more prominent."Mai Jing" written by Wang Shuhe in the Jin Dynasty is the earliest monograph on pulse study in my country.The 24 kinds of pulse conditions listed in the book have become the basis for the diagnosis of pulse in later generations."The Yellow Emperor's Three Acupuncture and Moxibustion A and B Classics" ("Jia and B Classics" for short) written by Huangfu Mi (mi Mi) is the earliest acupuncture monograph in existence, and it is also a classic of acupuncture and moxibustion. Needle retention time, moxibustion time, and acupuncture indications and contraindications, etc., have contributed to the popularization and development of acupuncture and moxibustion.In addition, "Shen Nong's Materia Medica Collection Notes" by Tao Hongjing in the Southern Dynasties, "On Paoxiu" by Liu Song Lei [Xiao Xiao], and "Elbow Reserve Emergency Prescriptions" by Ge Hong in the Jin Dynasty were also included in the study of Materia Medica, the processing and processing of medicines, and the science of prescriptions. On the one hand, it has enriched and developed the traditional Chinese medicine system of the motherland.The development of geography at this time is characterized by the emergence of a large number of "geographic records" describing the states, counties and mountains and rivers in various places, and several national general geographical records have also appeared successively.The "Shui Jing Zhu" written by Li Daoyuan of the Northern Wei Dynasty took the water system as the outline, recorded in detail the topography, products, and geographical evolution of the areas where the rivers flow, and wrote a new chapter in the development of geosciences.Due to the development of Taoism, alchemy became more popular in the upper class of society at that time. Ge Hong in the Jin Dynasty was a famous alchemist. The experience of predecessors has recorded the properties and chemical changes of many substances, and has contributed to the development of medicine and chemistry.

During the Sui and Tang Dynasties, the long-term stability and unification of the empire and the prosperity of economy and culture made ancient science and technology continue to develop and mature.Liu Zhuo in the early Sui Dynasty used Dingshuo instead of Pingshuo for the first time in the "Huangji Calendar" in view of the uneven movement of the sun and the moon, and created a quadratic equidistant interpolation method to improve the calendar.The transformation of astronomical instruments and large-scale astronomical observations in the Tang Dynasty provided more precise astronomical constants for the compilation of a more complete calendar. Measurement.In "Dayan Calendar", Yixing created the quadratic interpolation method with unequal spacing and the empirical formula for calculating the influence of parallax, and strengthened the systematicness of the content and structure of the calendar, indicating that the ancient calendar system of our country is fully mature.The progress of astronomical calendar is inseparable from the development and popularization of mathematics. For example, the quadratic interpolation method is not only an important method of calendar calculation, but also a great achievement of mathematical research.Both the Sui and Tang dynasties set up mathematics education in schools established by the state, and also set up Mingshu subjects in the imperial examinations. Ten important mathematics works in the Han and Tang Dynasties were used as textbooks, known as "Mathematics", and a lot of annotations were made on them Work.The "Ji Gu Suan Jing" among the ten calculation scriptures was written by Wang Xiaotong in the early Tang Dynasty.The development of agricultural technology in the Sui and Tang Dynasties, such as paddy field preparation techniques in the south, improvement of farm tools, construction of farmland water conservancy projects, increase in crop varieties and varieties, etc., created good conditions for the production of agricultural books.At this time, there were more agricultural works than ever before, both comprehensive and specialized, totaling more than 20 kinds.Zhuge Ying's "Planting Method" in the Sui Dynasty has 77 volumes. Lu Yu's "Tea Classic" is the earliest monograph on tea in my country and the world. agricultural book.The medical institutions in the Sui and Tang Dynasties were relatively complete, and the scale surpassed that of the previous generations, which was the only one in the world at that time.The government's attention is undoubtedly conducive to the development of medicine.The "Xinxiu Materia Medica" of the Tang Dynasty is the first pharmacopoeia promulgated by the state in my country and in the world. It contains 844 kinds of medicines, and it is rich in pictures and texts. It is also of great significance in the morphology of animals and plants.Physicians in the Sui Dynasty attached great importance to the study of etiology and disease symptoms. Dr. Chao Yuanfang, an imperial physician, was ordered to summarize the experience of predecessors and wrote "On the Origin and Symptoms of Various Diseases". A monograph on etiology and pathogenesis.Significant progress was also made in clinical medicine during this period. Sun Simiao's "Thousand Gold Prescriptions" and Wang Tao's "Waitai Secret Yao" collected the culmination of clinical prescriptions since the Eastern Han Dynasty, especially in the use of medicines.In addition, the Tibetan people formed a Tibetan medical system with national characteristics in the Tang Dynasty through long-term accumulation and absorption of the medical experience of the Han nationality and neighboring India. The "Four Medical Codes" compiled by Yu Tuo Yuandan Gonpo in the 8th century is a classic of Tibetan medicine and has laid the foundation for Tibetan medicine.The rulers of the Sui and Tang dynasties also attached great importance to the compilation of national geographical works, so as to grasp the conditions of mountains, rivers, products, household registration, customs, etc. of all parts of the country, which had a great impact on geographical works.Geographical works edited at this time were mainly in the form of "map classics", which consisted of maps and explanatory texts. "Hai Nei Hua Yi Tu", Li Jifu's "Yuanhe County Tuzhi" and so on.In the Tang Dynasty, the transportation between China and foreign countries was developed, and Xuanzang’s journey to the west was well-known to everyone. His "Da Tang Western Regions" is not only a work of geography, but also an important material for the study of Sino-foreign exchanges.

During the Song, Liao, Jin and Yuan dynasties, the unprecedented prosperity of the social economy, the government's incentive policy for scientific and technological inventions, and the exchanges of science and technology among various ethnic groups and between China and foreign countries promoted the development of ancient science and technology to reach its peak at this time.Song Zeng Gongliang recorded the recipe for making gunpowder in "Wu Jing Zong Yao", Shen Kuo talked about the production of compass and the invention of movable type printing in "Mengxi Bi Tan", plus Su Yijian's "Paper Book" in Song Dynasty, Yuan Dynasty With the appearance of paper-making monographs such as "Paper Notebook" written on behalf of others, almost all of the "four great inventions" in ancient my country were either invented or improved during this period, which shows the high development of science and technology in the Song and Yuan Dynasties.The scientific and technological works of the Song and Yuan Dynasties far surpassed the previous generations, both in quantity and in general.In terms of astronomy, Su Song's "Xin Yi Xiang Fa Yao" recorded the design and manufacture of the world's earliest "astronomical clock" and the design and manufacture of the water transport instrument platform; According to the calendar, it sets the length of the return year as 365.2425 days, which is only 23 seconds away from the current theoretical value.In terms of mathematics, Song and Yuan mathematics is the second climax of ancient mathematics research in my country, and it is also the pinnacle of ancient mathematics development. Mathematicians are as brilliant as stars, and their works have made brilliant achievements.For example, Song Qin Jiushao's "Nine Chapters of Shushu" proposed "Da Yanqiuyishu" (a method of solving the first-order simultaneous congruence formula); Equation); Yuan Zhu Shijie's "Siyuan Yujian" explained the solution of multivariate high-order equations, etc., and achieved world-leading achievements in different aspects.In terms of agronomy, there are not only large-scale agricultural books such as "Wang Zhen's Agricultural Book" that synthesizes the production experience of dry field farming in the Yellow River Basin and Jiangnan paddy field farming, but also "Chen Yan (fu Fu) Agricultural Book" that focuses on agricultural technology and management of rice in the south. The regional agricultural books on methods, as well as a large number of specialized agricultural books on sericulture, tea, flowers, fruit trees, etc., reflect the comprehensive development of agricultural technology during this period.In terms of medicine, the Song government organized revisions and published several large-scale herbal and prescription books such as "Zheng Lei Materia Medica" and "Taiping Shenghui Prescription"; "Respecting Parents", Li Gao's (Gao Manuscript)'s "Discrimination of Injuries from Internal and External Injuries", etc., and Zhu Zhenheng's "Ge Zhi Yu Lun" in the Yuan Dynasty, etc., inherited and developed the medical theory of the "Huang Di Nei Jing" from different aspects, forming the " The Four Schools of Medicine, Theory of Fire, "Short Theory of Attacking Evil", "Theory of Spleen and Stomach", and "Theory of Nourishment of Yin"; Song Wang's only "Bronze Man Acupuncture and Moxibustion" and Yuan Huashou's "Fourteen Classics" unified Each school's statement on acupoints; Yuan Qidezhi's "Surgery Essence" and Wei Yilin's "Shiyi Dexiaofang" are monographs on surgery and orthopedics respectively.These works indicate that TCM has entered a new stage of comprehensive development in terms of clinical experience, medical theory and herbal medicine.In addition, Song Ci's "Washing Injustice Records" is the world's first systematic forensic medical work, which was later spread abroad and has many translations.During this period, geography also made great achievements. The "Taiping Huanyu Zhi" compiled by Yue Shi in the Song Dynasty and the "Dayuan Yitong Zhi" compiled in the Yuan Dynasty are both brilliant works of local chronicles; "Stone Spectrum" is the most complete rock and mineralogy work preserved in my country so far; in addition, there are many local chronicles of counties and counties, travel notes and sea experience records, etc.The achievements in map surveying and mapping during the Song and Yuan Dynasties are also particularly outstanding, with large scale and sophisticated technology. Among them, stone carved maps such as "Huayi Map", "Yuji Map", "Geographic Map" and "Nine Regions Shouling Map" have always been Preserved to this day, it is a precious material for our study of ancient maps.Monographs on technology, such as Li Jie’s "Building Fa Shi" in the Song Dynasty, comprehensively and systematically summarized the experience of craftsmen in the past dynasties and the construction technology at that time; "System" is a monograph on woodworking technology, which contains detailed descriptions of textile machinery and has high historical value.Shen Kuo's "Mengxi Bi Tan" is the most comprehensive work that reflects the level of scientific and technological development at that time.The book involves a wide range of fields such as astronomy and calendar, mathematics, geography, geology, meteorology, physics, chemistry, metallurgy, weapons, water conservancy, architecture, animals and plants, and medicine, and has achieved important scientific achievements in many aspects. Coordinates in history".

In the early Ming Dynasty, due to the decline of the feudal system, the development of science and technology slowed down. In particular, the ruling policy of prohibiting folks from learning academic law directly restricted the development of certain disciplines.At that time, technology and applied science were more developed. For example, Wu Jing's "Nine Chapters of Algorithms and Classes" was a compilation of more than 1,000 application problems. The development of business mathematics.Zhu Zaiyu's "New Theory of Temperament Studies" invented the twelve equal temperaments and made a significant contribution to the development of temperament studies.After the middle of the Ming Dynasty, with the budding of capitalist production relations and a group of pragmatic intellectuals turning to scientific research, the development of traditional Chinese science and technology took a turn for the worse, and a number of famous scientific and technological works appeared in the late Ming Dynasty.For example, Li Shizhen's is a comprehensive work on pharmacology, Song Yingxing's "Tiangong Kaiwu" is the first encyclopedia about agriculture and handicrafts in my country and the world, and is a masterpiece of ancient Chinese geography. Xu Guangqi's "Nongzheng Quanshu" is a The master of ancient and agricultural technology at that time, Fang Yizhi's "Little Knowledge of Physics" made a comprehensive record of ancient scientific knowledge in my country on the one hand, and absorbed some scientific knowledge from the West on the other hand. It is an encyclopedic scientific knowledge book.These works are actually a large-scale summary of my country's ancient science and technology system.

At the end of the Ming Dynasty and the beginning of the Qing Dynasty, modern western science began to spread to my country, which had a huge impact on the development of science and technology in our country.On the one hand, some traditional sciences continue to develop, the more typical one is traditional Chinese medicine, such as Ye Gui's "Warm and Heat Theory", Wu Tang's "Warm Disease Tiaodian" and Wang Shixiong's "Warm and Heat Jingwei" in the Qing Dynasty. The pathogenesis and transmission of the disease, as well as the diagnosis and treatment of the disease, have been comprehensively studied, making the febrile disease theory reach a mature stage; Zhu Yiliang's "Vaccination Heart Method" records the selection and breeding of human pox drugs and the method of human pox vaccination; Zhao Xuemin's "Compendium of Materia Medica Supplements" and Wang Qingren's "Yielin Correcting Mistakes" also played the role of "recovering" and "correcting mistakes".On the other hand, a group of scientists devoted themselves to the integration of Chinese and Western sciences. The "Chongzhen Almanac" compiled by Xu Guangqi, Tang Ruowang, etc. in the late Ming Dynasty introduced European astronomy more systematically; The Essence of Mathematics is an encyclopedia introducing western mathematical knowledge; Wang Xichan's "Xiao'an New Method" absorbed the advantages of Chinese and Western astronomy, and independently invented the method of calculating gold and Mercury transiting the sun; Mei Wending, Li Shanlan, etc. There are also a large number of mathematical works published, which have made great achievements; others include Zheng Fuguang's "Mirror Mirror (Ling Ling) Chi" which describes geometric optics relatively completely, and Xu Shou's "Chemical Jianyuan" is a systematic chemistry textbook. ,etc.Although the number of scientific works in the late Ming and Qing dynasties was much larger than that of previous dynasties, in general, since the middle of the Ming Dynasty, my country's scientific and technological development has gradually lagged behind that of Europe.

Ancient Chinese scientific and technological works are like a river, which has been continuous from its source to the sea of ​​science in the world, and its inheritance and development are clearly visible.At the same time, we should also know that ancient Chinese science and technology have always been at the forefront of the world and had amazing brilliance. Only in the past two or three hundred years did they begin to lag behind the West.Revisiting history will strengthen our confidence. The Chinese nation is a hardworking and intelligent nation. Through hard work, we will surely be able to stand on the top of the world's technological field again.

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