What is science?

First, the origin of the word science.

The word science, in English, originated from Latin scio, later evolved into scientin, and finally became the writing method today. Its original meaning is knowledge and learning. Fukuzawa Yukichi, a famous Japanese master of scientific enlightenment, translated "science" into "science". 1893, Kang Youwei introduced and used the word "science". Yan Fu also used the word "science" when translating scientific works such as Evolution. Since then, the word "science" has been widely used in China.

Why do you call it that? The original meaning of science is systematic knowledge. I think maybe, in the19th century, science has become a very huge knowledge system. It is divided into many majors, and these majors are not related to each other like other knowledge. In addition to professional concepts, the basic concepts are the same, and the basic methods are the same. "Branch" means classification or hierarchy, so I think science is more suitable for "science".

Second, the strict definition of science.

In fact, because the word science has never been strictly defined, it will cause a series of confusion and unnecessary arguments. For example, was there any science in ancient China? Is TCM a science? What's the difference between science and pseudoscience? What is the difference between science and religion? Wait a minute. And these questions are very, very attractive. Therefore, the times require us to give an appropriate definition as soon as possible to solve these disputes. Let's take a look at the definition based on the existing textbooks and some authoritative works, which I think is very strict, and then discuss its exact meaning in order to win the unanimous approval of the academic community.

Definition-Science is a knowledge system that is closest to the truth and contains no contradictions as much as possible, and it is also a social undertaking.

In this definition, the attribute "the closest to the truth does not contain self-contradiction as much as possible" is added by myself, because it is to clarify the meaning of science, that is, to clarify what kind of knowledge system science is (I still don't understand why many books dare not add it clearly). Of course, "contradiction" refers to logical contradiction.

"Knowledge system" is people's initial understanding of science. As a practical knowledge, the most important thing is to be highly organized and structured. At this point, any classic work has this feature to some extent, and the most famous one in ancient times is Geometry. Perhaps the most organized thing in China's classical works is my ignorance. I think the secrets in Orange (a chess book) have the greatest influence on me. However, the scientific knowledge system is not as small as some knowledge systems and the scope of discussion is so narrow, but a very huge knowledge system, and its ambition even attempts to cover everything. It is unique that such a huge system still needs to maintain a strong order and structure. But there is not only one knowledge system, so it is necessary to know what kind of knowledge system science is. The definition is given in the previous part, so skip a paragraph and discuss it again.

People have long recognized that science is a social undertaking, but its significance is further deepened with the development of the times. And this is also difficult for people who lack education to understand. How can the knowledge expressed in books be a social activity? It cannot be understood by others, nor can it be repeatedly verified by others. This is not knowledge in itself. Why should we emphasize its sociality? This is because science's understanding of knowledge is much stricter than others. No matter for wizards, religious people, civilians or scientists, knowledge refers to correct statements and correct predictions, that is, knowledge is what people think of as "truth". But only scientists examine "truth" very strictly. We should not only see whether its initial statement (usually called axiom) comes from intuition, experiment or good reason, but also carefully examine any details in the process of derivation and see if any conclusions it derives conflict with experiments or life experiences. This series of work can't be completed by people without scientific training, so it needs education, the cooperation of many scientists and the understanding and support of the general public. With the development of science, the higher the complexity of science, the stronger its sociality.

"Closest to the truth" emphasizes the characteristics of science. Compared with others, science emphasizes doubt most, because science is based on the premise of no foresight. It is believed that all knowledge is people's understanding of the objective world. Although science pursues the unity of subjective world and objective world, after all, subjective world and objective existence are not the same thing. No matter how correct knowledge is, it is only close to the description of the world, not the description of the objective world. For example, the ideal gas model can describe oxygen, nitrogen and carbon dioxide at normal temperature and pressure very well, because the linearity of these gas molecules is much smaller than the distance between them. Van der Waals' revision of the ideal gas model only approximately describes the real gas such as water vapor. Scientists knew from the beginning that their theories were similar, so they never expected that the conclusions drawn from their theories were not wrong with the real world. All knowledge is man-made and the product of the subjective world. Even if there are aliens, they may just be more evolved than the people on earth, and they will be wrong. The secret of nature exists in nature itself, and nature expresses itself with its own diverse characteristics, but it will not be clearly expressed in the form of words through the mouth of God. It can be seen that the word "closest to the truth" not only emphasizes the rigor of science, but also emphasizes the significance of science to understanding the world.

The attribute of "not including self-contradiction as much as possible" embodies the pursuit of perfection in science and emphasizes that science also has a process of growth. Ordinary people often make mistakes, so do great men. The most respected figures like Newton, Einstein and Marx also have wrong theories. Russell's works often describe the contradictions of great men. For example, Malthus, who advocated birth control, added three children in four years; Schopenhauer, who advocated inaction, was ecstatic about the late honor; Bacon, known as the originator of experimental science, did not know that Harvey, who treated him, invented the theory of great blood circulation. Even so, it is very difficult to collect all the scientific contents of great men's wisdom without contradiction, and the bigger the system, the more difficult it is to be error-free, especially for new disciplines, which takes time to test. Any science has a mature process. In addition, with the development of the times, the original science may be an approximation in some cases, and there may be contradictions when it is infinitely promoted, and science will never pretend not to see it, but must solve this contradiction and make science develop forward. Relativity caused by Michelson's experiment, quantum mechanics caused by blackbody radiation experiment and mathematical revolution caused by Barber's paradox all developed after eliminating those contradictions.

In my opinion, the above definition of science not only expresses the classical scientific meaning with the least words, but also highlights the characteristics of science, clarifies the boundary between science and others, summarizes Kuhn's scientific paradigm theory and Popper's falsification theory, and emphasizes the evolutionary characteristics of science.

Third, scientific methods.

To truly understand science, it is not enough to understand the definition of science. But understanding science does not necessarily require mastering a lot of scientific knowledge. If you want to understand the shortcut of science quickly, you must master some main scientific methods.

Science is seeking truth, that is, how to get a true statement. There are two classical scientific methods, namely experimental method and rational method, specifically induction and deduction.

Induction: a method of upgrading a special statement to a general statement (or a law principle or theorem). Empirical science comes from observation and experiment, and a large number of original records are merged into a few laws and theorems, forming an orderly knowledge system. This is the process of the formation of empirical science. It can be seen that what kind of induction is effective and reliable is the most important issue to be studied by empirical science. Since the extension of science in the strict sense, the exploration and debate in this field have never stopped. It can be seen that with the deepening of research, it is found that this is a very complicated problem. Far more complicated than deduction. Perhaps it is for this reason that education does not pay attention to the popularization of scientific methods, which makes the public accept scientific knowledge and other knowledge seem to be the same, so that they can't tell what is scientific knowledge and what is non-scientific knowledge. It is impossible to discuss the complete content of induction strictly here, but in order to explain the following series of problems, here are some basic points of induction.

Induction can be divided into complete induction and incomplete induction, in which the scope of application of complete induction is very small, because for most things, observable phenomena are often infinite. Therefore, practical induction must be incomplete induction. It can be divided into two types, namely simple enumeration and scientific induction. Simple enumeration method is unreliable and can only get probable truth, so scientific induction is the center of scientific method discussion.

The so-called scientific induction, also called exclusion induction, does not necessarily add original sentences, but excludes possible assumptions and can be applied to specific cases. Bacon's "three tables method" and Mill's "five tables method" are all of this type. The following is a brief list of Mueller's "five methods". Note that their premise is that there are only two phenomena, and each phenomenon has only three elements, namely, A, B and C (phenomena) and A, B and C (causes). They all assume that ① there is only one condition (cause) for A, and ② only A, B and C are possible conditions (causes).

1, in accordance with the law: A and AB appear together, and also with AC. It can be seen that A is a sufficient condition for A. For example, two wheat fields with nitrogen fertilizer (A), one with water (B) and calcium fertilizer (C) have higher yield (A). It can be guessed that fertilization (a) is the reason for increasing yield (a).

2. Difference method: A appears with ABC, but does not appear with BC, indicating that A is a necessary condition for A. For example, Example 2: Applying nitrogen fertilizer (a), water (b) and calcium fertilizer (c) in wheat field leads to an increase in yield (a); However, only watering (b) and applying calcium fertilizer (c) will keep the yield unchanged in another wheat field. It can be guessed that fertilization (a) is the reason for increasing yield (a).

3. fitting difference method: a and AB appear, but also with AC, but not with BC. Therefore, A is a necessary and sufficient condition for A. For example, in Example 3, two wheat fields were irrigated with nitrogen fertilizer (A), one with water (B) and the other with calcium fertilizer (C), and the yield increased (A), while the other wheat field was only irrigated with water (B) and calcium fertilizer (C), and the yield remained unchanged. It can be further affirmed that fertilization (a) is the reason for increasing yield (a).

4. Residual method: It is known that B is the condition (cause) of B, C is the condition (cause) of C, and abc appears together, indicating that A is the necessary and sufficient condition of A. For example, 4: Astronomers observed that Uranus' orbit is tilted (A, B, C), and it is known that the tilting phenomena A and B are attracted by two planets (A, B), so we can guess another planet (C).

5.* * * Reform: A and A change in the same way, while BC does not change in this way. Therefore, a is a necessary and sufficient condition. Example 5: Changing the pendulum length (a) of a simple pendulum will change the period (a) of the simple pendulum, but changing the mass (b) and the material (c) of the pendulum will keep the period unchanged. It can be considered that the pendulum length (a) of a simple pendulum determines its period (a).

Through scientific induction similar to that of john stewart Mueller above, it seems easy to find the causal relationship of things, but in fact it is very difficult. As far as john stewart Mill is concerned, these two premises are the most difficult to satisfy. The first one is called determinism postulate. With the emergence of quantum mechanics and chaos, there are not many deterministic systems in the real world, so this presupposition is not always satisfied. The second is called closed system postulate, which is the most difficult to satisfy in scientific research. For example, although the fitting difference method is a very effective research method for deterministic systems, as long as the system is complex, its closeness is difficult to satisfy. It is easier to find out what the possible reasons are (pendulum length, quality, material, etc.). For a simple system like a simple pendulum, it is behind a phenomenon (such as period), but Example 3 is not simple. In fact, there are many possible reasons that affect the yield of wheat fields, so the actual research is by no means as simple as Example 3.

So much has been said about induction, which really comes from refugees. It takes a lot of time to make people understand that induction is the biggest problem in science, but it takes a lot of time to make people understand science without emphasizing this point. With regard to experience, modern philosophy may not focus on induction, but mainly discuss the most basic problems of empirical science, that is, how to describe phenomena and what kind of description is meaningful. Phenomenology, logical positivism and very obscure philosophy of language all remain in this discussion. Indeed, these are very important. In fact, the greatest contribution of Bacon, the originator of experimental science, is not to summarize, but to emphasize how to get the correct original statement. If the initial statement is incorrect or meaningless, then subsequent induction and deduction will be futile.

Deduction: A method of deriving a special statement or another statement from one statement by applying general statements (or principles of axioms and theorems). At first glance, deduction doesn't seem to get anything new, so Bacon's sharp criticism of Aristotle's syllogism is not groundless. But if we change our thinking and seriously think about what is "new", we will find the importance of deduction. From Newton's connection between the movement of stars in the sky and the falling of apples on the ground to today's grand unified theory, we can see that there is indeed a unified essence behind material phenomena, so we can completely deduce the correct statements of various phenomena in the world with few sentences. In this sense, "new" does not necessarily mean a statement outside the old system, as long as it is another statement that has never been seen before, because all statements with practical significance can be placed in a scientific system.

Descartes seemed to realize this, so he looked down on Bacon very much, and finally established a truly practical rational building through his efforts. He saw the deductive power of mathematics and raised the rational thinking of ancient Greece to an unprecedented peak. Descartes is often called the father of philosophy and science in the west, and I agree with him very much. When did strict science begin, not from Copernicus, not from Bacon, not from Galileo, but from Descartes? Strictly speaking, there is no science without mathematics. Without the participation of mathematics, any science is difficult to be effective, let alone mature.

But mathematics is often not called empirical science, or even metaphysics, because mathematics is often a theoretical system derived from several axioms. For example, The Elements of Geometry only deduced a thick book from five axioms, while the fifth postulate was changed to derive Roche geometry and Riemann geometry. Mathematical axioms often come from intuition, so they are often called transcendental science. In fact, there is not much essential difference between them, but the laws and theorems in empirical science are not as intuitive as mathematical axioms. Euclidean geometry is the study of real space, and of course it is easy to get several axioms intuitively. Algebra and number theory are only logarithmic sum equations, and of course they may be based on several intuitive axioms. However, if it wants to study all space-time matter together, the laws and theorems of relativity are not obvious. Mathematics is considered to be the most abstract, in fact, it is its abstraction that considers the foundation. The more specific, the more factors involved in the research object. Why geometry is the basis of science is precisely because everything occupies space and algebra is the basis, because all concepts must be quantified in order to study accurately. Abstraction has two meanings, one is a description of something, and the other is difficult to understand and imagine. Of course, many times these two meanings are both, because the incomplete description is not specific and it is hard to imagine. However, the abstract theory is practical precisely because we always like to describe and deal with specific things part by part. Therefore, abstraction is often basic. Descartes clearly recognized this and further put forward some principles that must be observed in scientific research:

(1) only put those things that are very clearly presented in front of my mind and wisdom, so that I can't doubt them at all in my judgment;

(2) Decompose the problem into small parts as much as possible until it can be solved satisfactorily;

(3) Start with the simplest and easiest object to know, and get to know the complex object bit by bit.

(4) List all situations as completely as possible, and inspect them as widely as possible to ensure that there are no omissions.

These principles are very incisive, but the first point ignores the role of experiments. The whole classical science is based on these principles. Although modern science has supplemented the classical scientific method, the above-mentioned classical scientific method is still the most basic and main method of science. So-called analogy, simulation, experiment, analysis and synthesis, hypothesis, etc. It should also belong to the classic scientific method. The function simulation method, black box method and information method developed from system theory, information theory and cybernetics can only be regarded as the supplement of scientific methods, even in today's computer processing capacity. This inverted cognitive process from the whole to the details can't be the mainstream method in any case, and it can only be used when necessary.

Judging from the achievements of mathematics applied to various sciences, there is a very obvious problem in saying that deduction can't get anything new. Comparatively speaking, deductive method has more initiative and freedom than inductive method, because deductive method can freely choose initial axioms and formulate rules of deductive method, thus creating a large number of theoretical systems. Once a certain part of the real world is found to be applicable, these theoretical systems will immediately show its great role, such as Riemann geometry used in relativity and group theory used in particle physics. In addition, induction itself often needs deduction, and the correctness of a sentence needs to be reflected by numbers. Because of the addition of mathematics, the induction procedure is greatly reduced and the induction efficiency is improved. For example, according to the wave-particle duality of light and the detailed investigation of the development process of physics, De Broglie deduced that all particles may have the correlation of wave-particle duality, which is almost deductive. But according to this hypothesis, the results of electron diffraction can be predicted quantitatively. Through the quantitative comparison between the experimental phenomenon record and the theoretical deduction statement, the correctness of this hypothesis can be roughly known from the matched effective figures. Obviously, significant number is the core theory of the experiment. Having two valid numbers matching means that there is only a few percent error probability, and having eight numbers matching means that there is only a 100 million probability of being falsified. So the quantitative experiment is actually to make up for the defect of incomplete induction. A few precise experiments can roughly confirm or disprove the hypothesis, otherwise, theories that are difficult to observe, such as general relativity, cannot be recognized by people.

At this point, we should be able to understand why mathematics is the queen of science. In some philosophers, the difference between rationalism and empiricism is often compared with the inverted pyramid and the right pyramid. It is believed that once a certain principle or principle of transcendental system is falsified, the whole system will go up in smoke, and even if several principles of empirical system are denied, the pyramid will not fall down like removing a few stones from the bottom of the pyramid (for example, Newtonian mechanics belongs to empirical science, and it has not collapsed because relativity overturns several of its theorems). Such an example is very vivid and appropriate, but it is easy to despise reason. In fact, this analogy only warns us to be cautious in applying artificially constructed theories, and rationality is the essence of science, because deduction is not only used to construct theories and apply theories to derive sentences, but also dissolved in the process of induction. Science is inseparable from logic and reason.

"The scientific method seems boring and difficult to understand, but it is much more important than scientific discovery." International popular science theorists believe that scientific methods are the most important content in scientific literacy. The most important thing for the public to understand science is to understand scientific methods and apply them to solve various problems in life and work. In real life, some people's blind obedience behavior is also related to the lack of scientific methods. Especially in our country, which lacks rational foundation, we should emphasize learning scientific thinking methods.

Fourth, scientific spirit.

Because science is often associated with technology, it is easy to forget that science is a part of the superstructure, especially in the backward society without rational tradition, and even a large number of people do not know that there is scientific spirit. It is true that few people summarize and generalize the scientific spirit, and few people publicize it. It is for this reason that the influence of science on backward countries is not great, at least not all-round.

Although I have taught the course Introduction to Science and Technology for several years, I haven't found a systematic exposition of the scientific spirit. The following is a brief summary of my scattered data. Merton, an American scientific sociologist, believes that universality, public ownership, selflessness and organized skepticism constitute the spiritual temperament of science. Professor Cai Decheng in China summarized the scientific spirit as "six elements", namely: objective basis, rational doubt, multiple thinking, equal debate, practice test and tolerance and encouragement. Many of these two scholars know each other. More specifically, I use the following words to summarize the scientific spirit: justice, simple thinking, proof plus falsification, rational doubt, demonstration and encouragement. Here are some explanations.

(1) Justice: Observe things from the standpoint of justice. I call this scientific spirit Copernicus spirit. Some people say that modern science began in Copernicus. Although I disagree, I am amazed at the greatness of Copernicus' spirit. Without the Copernican spirit, there would be no science. From this point of view, Copernicus spirit is indeed the forerunner of modern science. Because observation always starts from its own perspective, it is difficult for people to imagine and think about phenomena without their own perspective in the natural state, so they unconsciously form a self-centered concept. When ideas become rigid with age, it is very difficult to see problems from a certain height, so it is not easy to grasp things. So justice is the basis of scientific thinking. In fact, the development of science has strengthened the sense of justice more and more. The emergence of the theory of relativity makes people realize that not only the earth where we live is not the center of the universe, but also the centers of the sun and the Milky Way are not the center of the universe. /kloc-the main defect of Marx's theory in the 0 th and 9 th centuries is that it emphasizes the position too much. Social science must also break the framework of class and establish a unified system without contradictions. There should be no social science theories of two opposing classes. In fact, modern self-organization theory has taken this step.

② Simply start with multiple thinking: choose simple objects to start research, establish ideal models, apply mathematics as much as possible, comprehensively consider all elements, establish theories, and expand the application scope through modification and expansion. This is actually the scientific thought put forward by Descartes mentioned earlier, so it is called Descartes spirit. Newton's particle model and Clausius' ideal gas model have not only achieved great success in physics, but also in other fields. For example, Moore in the biological world was lucky to choose the simple object of Drosophila, which opened the prelude to genetic research. The most important thing for a correct understanding of things is to avoid one-sided thinking and have diversified thinking, but the brain's ability to process information is limited, so choosing simple objects first can avoid thinking too much. More complex problems can be solved by overlapping the conclusions from studying simple problems in various ways, and more complex problems can be quantitatively approximated and qualitatively analyzed by existing conclusions.

③ Proof plus Falsification: Science is strict, which emphasizes the consistency between theory and practice, that is, any deduction statement of a theory must be consistent with observation. It can be proved by experiments that a theory that cannot be falsified is not science. We call it the Popper spirit. There are many new theories in modern science without much experimental support, which often come from artificial deductive structures. As long as one of these knowledge systems is different from observation, it should be overturned. But for empirical science, experience precedes theory, so don't believe falsification easily. Even if a statement is falsified, we should first consider revising it, or embrace the old theory with a bigger theory.

(4) Rational doubt: Science is only the closest to the truth, the truth of things is only known by things themselves, and any knowledge system is artificially constructed. Science places special emphasis on doubt, including self-doubt. However, since science has lasted for more than 300 years, many scientific fields have almost matured through the careful development of countless skeptical scientists, so doubt needs a certain rational basis. Descartes and Marx, the two most influential figures in the history of science, both took "doubt everything" as their inscriptions. Because people who believe in * * * productism just ignore Marx's skeptical spirit and believe in dogma too much, in order to warn this, I call it Marxist spirit. Although today's scientific reliability is far more reliable than that of the two great men, and the skepticism about science remains unchanged, you can't blindly doubt without scientific training. When you want to doubt a scientific conclusion, you have to know whether you meet the standard, because simple doubt has been doubted countless times. Especially some classical theories, such as Euclidean geometry, algebra, kinematics, etc., are composed of few axioms and laws. For example, the five axioms of Euclid geometry are quite intuitive, and none of them come from experiments. The theory derived from this has been verified by countless people for thousands of years and can be said to be completely reliable. The reliability of kinematics is the same, except that there are experimental laws (such as parallelogram law of velocity synthesis) in kinematics principle, so the reliability is not as good as Euclidean geometry. Why is the theoretical system with experimental laws weak in reliability? This is because the experimental law is limited by the experimental conditions, and the applicable conditions are often unclear for a while. For example, Newton's law is generalized at a low speed, so people will make mistakes if they think it is universally applicable and infinitely popularized. In this sense, empirical science is not as reliable as pure science. A completely artificial theory can easily be completely free from logical contradictions. It is not easy for such a theory to find a complete correspondence in the real world, that is, the unreliability of the inverted pyramid of pure science lies in its application. The spirit of doubt is often used in life and is colorful in the world. You must keep your eyes open to distinguish what is scientific and what is not. Skepticism is mainly used to doubt non-scientific content. When things happen, think more and don't follow blindly. In our country, blind worship, conservatism, lack of innovative spirit and excessive traditional power can be said to be caused by lack of suspicion. It is the educational model of the current college entrance examination system that stifles the spirit of doubt. Examination questions always require a unique answer to the questions. Any doubt about the questions themselves is superfluous and will definitely affect the scores, so both teachers and students agree not to do any "superfluous" thinking. Therefore, the phenomenon that education revolves around exams should arouse our deep thinking.

⑤ Demonstration and encouragement: Science is artificial, so it is related to people's quality. Argument and encouragement can improve people's quality quickly, so science needs an environment for discussion to keep people's enthusiasm for science. I think Bohr is the best scientist in this field, so I call it Bohr spirit. The fierce debate between Bohr and Schrodinger and the collective contribution of Copenhagen school centered on him finally established quantum mechanics, which is a miracle of mankind. Bohr and Einstein also argued all their lives. In contrast, our environmental academic atmosphere is so bad that there is so little discussion, and a little argument will hurt feelings. How can such a fragile temperament contribute to science? Modern science is a social undertaking, far from being achieved by individuals. Why are there so many philosophers in Little Germany and so many famous scientists in Little Cavendish Laboratory? Why do Bell and Microsoft have so many inventions? All these show that the scientific environment is too important. If a society really attaches importance to science, it should first attach importance to the creation and maintenance of the scientific environment. Primary and secondary schools should cultivate the level of debate, universities should have more academic activities, academic authorities should learn more from Einstein, try to find and recommend new people, pay attention to cultivating scientific ethics, despise and crack down on scientific plagiarism and counterfeiting, and protect intellectual property rights.

How much scientific spirit needs to be discussed. I think that summarizing the scientific spirit into the above five kinds and naming them after five famous scientists can better highlight the characteristics of science and help us popularize scientific ideas on a large scale and create spiritual civilization.

Verb (abbreviation for verb) The difference between science and technology.

The word "technology" means carpenter, which may be the reason why carpenters were the most skilled craftsmen in ancient times. The definition of technology is people's various specific skills, experiences and specific knowledge in production activities.

People often think that the difference between technology and science is just a fragmented system. Actually, it's not. Technology is not necessarily piecemeal. Some technologies not only constitute a system, but also are very large and special modern technologies, such as shipbuilding technology, aerospace technology and atomic energy technology. So what is the difference between technology and science?

First of all, technology organizes knowledge and skills around specific production objects for easy application, while science organizes knowledge from epistemology for easy learning and exploration. Secondly, technology focuses on whether knowledge can be quickly transformed into wealth, focusing on innovation rather than understanding the essence of things, so its ability to expand knowledge is weak; Science focuses on explaining the essence of things, so it has a strong potential to expand knowledge, but because science does not organize knowledge from the perspective of specific applications, its practicality is not as good as that of specific technologies.

Science and technology have many overlapping contents, but they have relatively independent systems. Therefore, since ancient times, the development of science and technology has been independent, and the contribution of each nation to the development of science and technology is different in different historical stages. In ancient times, most ethnic groups had their own scientific and technological achievements, especially in ancient China, where there were brilliant scientific and technological inventions, including the four great inventions. In ancient Greece, on the contrary, scientific achievements shone like a dazzling pearl on future generations of mankind. The close combination of science and technology is a modern thing. The accumulation of technical knowledge provides scientific materials, and the accelerated expansion of scientific knowledge and the needs of social and economic development make technology consciously ask for food from science. At present, almost all developed countries are integrating science and technology, but unfortunately, most governments in developing countries are busy developing production with science and technology in the face of huge economic gap, without paying attention to the importance of science itself. Although the following words are harsh, they should really arouse our vigilance in China. Henry Roland, a famous American scientist, said in A Few Words to Pure Science: "If we want to use science, we must make it independent. If we only pay attention to the application of science, it will inevitably hinder its development. It won't be long before we degenerate into China people. Their generation has not made any progress in science, because they are only satisfied with the application of science and do not discuss the reasons for doing so at all. " "Unfortunately, the idea that science is mainly for economic development has spread to many other countries, and the freedom of scientific research has been endangered. Science is mainly a free research activity that pursues pure knowledge. If the actual benefits follow, even if they are discovered due to government funding, they are by-products. If we ignore freedom and pure science, applied science will wither and die sooner or later. " In the era of knowledge economy, the ratio of mental labor to manual labor is 9: 1.