What is general education? According to the general education concept expressed in the Harvard general education red book released by the Harvard Committee, students should have four abilities. First, effective thinking ability, including logical thinking, relational thinking and imagination; Second, communication ability, the ability to express themselves and be understood by others, and effective expression is inseparable from good thinking; The third is the ability to make appropriate judgment, which involves the ability of students to apply all their thoughts to the field of experience; The fourth is the ability to distinguish values. This ability not only means to have a clear awareness of different types of values, but also to understand the relationship between them.

Facing these four ability requirements, in my opinion, the general education of civil / geotechnical students should put the cultivation of mechanical thinking in the first place. In short, the first is to think in the language of mechanics within the framework of mechanics, which involves logical thinking, relational thinking and imagination. Secondly, we should also use the language of mechanics when communicating, otherwise it is easy for chickens to talk with ducks and ducks and can't understand each other. Thirdly, improve the ability of judgment, that is, the ability of flexible and comprehensive application on the basis of mastering the internal relationship between various mechanics courses. Finally, the ability to distinguish value, that is, what conforms to mechanical / mathematical logic is valuable, otherwise it will be suspected of pseudoscience.

In short, for students majoring in civil engineering, general education is not fancy boxing and legs, but hard practice of mechanical internal skills. Analogy is the highest standard of general education.

First, let's talk about the importance of logical thinking training. In my memory, our Chinese students were exposed to the study and training of logical thinking. Only when they studied plane geometry in junior middle school, there was little training in this field since then. Even the most basic logical syllogism may not be understood and mastered by many students. In my opinion, the lack of logical thinking is the main reason why most people lack judgment and appreciation of scientific problems or achievements.

In a sense, the ability of logical reasoning is the ability of independent thinking. Everyone is equal before truth, in fact, everyone is equal before logic. When my friend's children were in primary school in Australia, my friend inadvertently communicated with them and found that their school teachers were imperceptibly influencing her to judge whether a thing is right or wrong. An important measure is "make sense". My understanding is whether it is logical. This is not difficult to understand. At international conferences, many young people abroad look "neither big nor small", and are not modest enough. They do not give face to big professors or scholars when discussing problems, because their education has always been to discuss problems, not to people. The thing here is objective truth, and the principle is whether it conforms to logic. Many conferences in our country are talked about by big professors, and few people listen to them. There are fierce debates and questions, which is unfavorable to the generation of original innovation. A very important reason here is that there is no recognized criterion in everyone's mind, that is, logical criterion. Of course, it should be emphasized here that there is no contradiction between the fierce debate in front of the truth and the mutual respect between people.

Students majoring in civil engineering have studied theoretical mechanics, material mechanics, elasticity and soil mechanics at the university or graduate level. Mechanics and mathematics are based on rigorous logical reasoning. So, what is the relationship between these mechanics courses?

First of all, theoretical mechanics provides the basis of mechanical theory. Mechanics of materials studies nothing more than strength (failure), stiffness (deformation) and stability. As a material, soil still studies three problems: soil strength (failure problem), deformation (such as consolidation problem) and stability (such as slope stability problem). There is no difference between the two at this point. But their research methods are very different.

What's the difference? Let's first talk about the differences and relations between mechanics of materials and elasticity. Firstly, the research object of mechanics of materials is limited to slender structures such as rods, beams and columns, and there is nothing to do with complex structures. Elasticity can study structures of any shape. In addition, "mechanics of materials" is only an engineering approximation, while elasticity has strict mathematical derivation. In other words, elasticity not only solves the shortcomings of mechanics of materials, but also provides a mathematical basis for the establishment of soil mechanics.

As we all know, elasticity is nothing more than three kinds of equations: equilibrium equation (3 equations), geometric equation (6 equations) and physical equation / constitutive equation (6 equations). There are 15 equations in total, and the three-dimensional problem has exactly 15 unknowns (6 stress variables, 6 strain variables and 3 displacement variables). This can be solved mathematically, but it is not easy. Soil mechanics is based on elasticity. The connection and difference between them is simply to modify these three kinds of equations according to the characteristics of soil itself. For example, if soil is a three-phase medium, the contribution of water and air should be considered in the equilibrium equation. The geometric nonlinearity of soil is reflected in the modification of geometric equation, and the plasticity of soil needs to modify the constitutive equation. Computational soil mechanics uses computers and numerical methods to solve these three kinds of equations, which are finally reduced to solving equations. For example, the core of finite element is to solve the total stiffness matrix equations. In other words, soil mechanics combines mathematics and geotechnical engineering by solving partial differential equations. What does mathematics mean? It is the basic courses such as advanced mathematics, numerical analysis, linear algebra, probability theory and mathematical statistics, mathematical physics equations and so on.

This example is to illustrate that a very important point of the so-called general education is to internally connect the curriculum knowledge learned and achieve mastery. Only in this way can we form our own knowledge system, flexibly use and innovate. In addition, graduate and doctoral students will have a common language on the same channel only when they have a deep grasp of these knowledge and discuss with others. This is the importance of foundation. Without a solid foundation, there is no innovation at all.

Professor Qiu Chengtong, the winner of the fields prize, once said: "up to now, Chinese theoretical scientists still can't compare with the most advanced level in the world in terms of originality. I think an important reason is that our scientists are not enough in humanistic cultivation and have not rich feelings for the truth and beauty of nature!" in my opinion, music Painting, like mathematics, is a way to reveal the truth and beauty of nature, but from different angles.

Some people say that music is a flowing line. A good concert shows people a beautiful picture, and the beauty of mathematics and mechanics lies in its structure and simplicity. All literary works are nothing more than answering a question, that is, what is truth, goodness and beauty. The writer's ability to control and appreciate the structure of literary works is similar to that of mathematicians and mechanics in the construction of theoretical model structure. Of course, this is a beautiful blueprint for general education. However, general education must not be utilitarian, and its influence should be latent. This is logical.