Recently, the setting of interdisciplinary has become a hot topic in domestic academic circles. On October 30, 2020, according to the official website of NSFC, NSFC established the ninth University Department: cross science department, which is also the new science department established by NSFC after 11 years. Then, on January 15, 2021, the Academic Degrees Committee of the State Council and the Ministry of Education issued a notice to newly set up the "interdisciplinary" category, making it the 14th discipline category in China. At present, there are two first-class disciplines, namely "integrated circuit science and Engineering" and "national security". Don't underestimate the significance of this round of reform for the construction of China's science and technology system: Interdisciplinary has become a formal discipline in national education since then, which means that a series of institutionalized arrangements such as relevant majors, enrollment, degree award, achievement recognition and professional title evaluation can be established and made legitimate. In addition, the fund alone ensures that emerging interdisciplinary disciplines can obtain stable financial support from resources, which is very important for the development of any discipline. Objectively speaking, this round of reform is almost in place in one step from institutional arrangement to resource allocation. It can be seen that under the treacherous international situation, the country's active breakthrough path on how to accelerate scientific and Technological Development and break through the neck technical constraints. The setting and promotion of cross science is the best representation of this effort and determination.

Interdisciplinary phenomenon is nothing new. It has appeared for many years. According to the research of American interdisciplinary expert Julie Thompson Klein, the historical origin of interdisciplinary phenomenon in natural science can be locked in the 1940s-1950s, while the interdisciplinary phenomenon in the field of social science is earlier, which generally occurred from the end of World War I to the 1930s, A large number of methods are borrowed from the field of natural science to the field of social science. Looking at the short development history of interdisciplinary phenomenon, we can generally find that there are two main driving forces generated by interdisciplinary phenomenon: the first is exogenous driving force, which originates from the lasting driving force brought by the real social problems (social needs) and the need for colleges and universities to fulfill all their social responsibilities (serving the society). The second is the endogenous power, which mainly comes from the desire of the discipline itself for the production of new knowledge. In the real world, the emergence of interdisciplinary phenomenon is the result of the joint promotion of various forces. In the era of globalization, due to the intensification of competition, the pace of interdisciplinary is accelerating, and the driving force from external sources is stronger than that from internal sources, which is mainly due to the complexity of the problems encountered by society, These complex problems cannot be solved by any single discipline alone. This situation promotes the acceleration and expansion of the interdisciplinary process.

Generally, there are two paths for interdisciplinary from implicit to explicit: the natural evolution path (gradual) of discipline and the artificial design path (radical). The former is the inevitable product of discipline development to a certain stage, while the latter is the result of active design by government and society through institutional arrangement in order to achieve some specific goals. For the interdisciplinary phenomenon of natural evolution model, the development of discipline usually goes through the following development stages: specialization fragmentation mixing. Once the discipline completes specialization, it means that it has specific research categories, methods, means and concepts. The further development of specialization is the fragmentation of knowledge, The knowledge of the original discipline will cross the border and penetrate into other fields, which will produce the phenomenon of interdisciplinary. There are many such cases in the history of science. Once the interdisciplinary discipline is established, it will open up a new growth point of knowledge. As Klein said: the deeper the degree of specialization, the more the number of majors, and the greater the possibility of professional scholars meeting on the edge of other disciplines. Specialization produces more and more narrow fields. As a result, almost all fields involve the intersection of more than two disciplines.

After any discipline develops to a certain extent, there will be an insurmountable knowledge barrier. The more mature the discipline, the more obvious this barrier is. At this time, the mature discipline will penetrate into the discipline with a lower degree of development. The reason is that from the perspective of economics, the penetration and cross-border of resources (human, financial and material) into disciplines with low degree of development will bring the effect of increasing the marginal output of knowledge. In other words, the original resources are easier to produce results in areas with low knowledge gradient, resulting in large-scale knowledge penetration and cross-border phenomena, This is the internal dynamic mechanism of interdisciplinary phenomenon. When the disciplines with low knowledge gradient develop rapidly due to the cross-border of mature disciplines, resulting in the overall improvement of the global knowledge gradient, this situation will in turn promote the development of the original advantageous disciplines and help them overcome the original barriers. After countless cycles of this positive feedback, science and technology show a state of progress in the macro. There are many such cases in the history of science. For example, the Austrian physicist Erwin Schrodinger (1887-1961) put forward the theory of quantum wave mechanics in 1926 and won the Nobel Prize in physics in 1933. From the perspective of discipline potential energy, physics was the discipline with the highest knowledge potential energy at that time, and it was very difficult to make a major breakthrough. At this time, biology was a discipline with very low potential energy compared with physics. Therefore, his research interest turned to life science and published what life is in 1943, which directly revealed life phenomena from the perspective of physics, This is a typical cross-border discipline: the cross-border from high potential energy discipline to low potential energy discipline, which led to a group of physicists to devote themselves to the field of life science, which also opened the way for the birth of molecular biology.

Therefore, interdisciplinary is an inevitable trend after the development of science to a certain extent. It is reasonable to speed up this process through institutional arrangements. However, to achieve the purpose of interdisciplinary, we need to deal with the following three problems: first, clarify which disciplines have the basis for interdisciplinary? There are two situations that need to be vigilant. First, a discipline has been highly specialized and mature, and there is an obvious knowledge potential energy difference with adjacent disciplines. This kind of discipline can identify interdisciplinary disciplines through institutionalization; Second, we should be vigilant against the phenomenon of pulling up seedlings and encouraging them. If the maturity of the two disciplines is not high, the degree of specialization is not very high, and the knowledge potential energy difference between the two disciplines tends to be the same, then even if there is an intersection between the two disciplines, it is still in the primary stage. This kind of discipline intersection is not easy to be handled through institutional arrangements, and the purpose of discipline intersection can only be realized through the natural evolution model. Secondly, how to establish these new interdisciplinary paradigms? Here, we need to be vigilant against the phenomenon of pseudo discipline intersection, that is, forcing to accept a paradigm with epistemological advantages as an interdisciplinary paradigm, which is a typical pseudo discipline intersection. Third, in order to ensure the normal development of interdisciplinary talent training and knowledge output, what disciplinary boundaries and evaluation criteria should be established? Generally speaking, the discipline boundary is more determined by the method, theory and conceptual framework. Therefore, the establishment of a new discipline needs a clear problem domain, method, concept and technology. These things that constitute the discipline skeleton are by no means a simple summation of the two disciplines, but an organic integration in the development. Otherwise, how can it be distinguished from the original disciplines? All this needs to be slowly integrated in scientific practice. On this basis, we should build a targeted talent training system and evaluation system. Only in this way can interdisciplinary become a new growth point of knowledge production and release the incentive effect of institutional arrangement.

In short, at the moment when the whole country binds the engine of development to the path of scientific and technological innovation, how to increase the output of knowledge has become the primary task for the smooth realization of the national strategic goal. If the judgment is accurate, accelerating the process of discipline intersection through institutional arrangement is the most positive and effective attempt, which is also an important measure for us to improve the competitiveness of science and technology, break through the neck constraint and start the lane change race in the era of globalization.