Zhang Xuefeng repeatedly emphasized that AI = mathematical modeling = mathematics. DeepSeek was developed by mathematics PhDs. Mathematics is a jack-of-all-trades; a mathematics PhD can easily switch between fintech, internet, AI, and semiconductors. There are two core concepts I've been discussing for nearly 10 years. One is that computation is computation, a model is a model, and mathematics is mathematics. Computer science, electrical engineering, aerospace, mechanical engineering, finance—a vast amount of theory is expressed using calculation formulas. Most people who don't understand mathematics or these fields would assume, "Mathematical formulas = mathematics." The correct understanding is that each industry has over a dozen courses, corresponding to over a dozen large and small subfields. All the theories and professional knowledge in these fields are expressed using formulas and symbols, using basic tools like matrices, calculus, and probability. However, the essence of these theories and professional knowledge is the knowledge itself. The fact that they are expressed with symbols and formulas does not mean "all professional knowledge = mathematics." Many vocational school graduates don't understand this principle and readily claim, "Symbols = mathematics," "Modeling = mathematics," "What looks like a mathematical formula = mathematics," "Learning mathematics allows you to solve all professional formulas and problems," "Studying mathematics to a doctorate allows you to solve all mathematical problems in finance, internet, AI, semiconductors, materials, and mechanical engineering." The correct understanding is that "Formulas, symbols, tools, theories, and models = quantitative symbolic expressions of knowledge in various subfields"—they have absolutely nothing to do with mathematical theory itself. Another key point is that mathematics is mathematics, and mathematics will always be mathematics. The field of mathematics has very clear and defined boundaries, whether at the undergraduate, master's, or doctoral level. The field of mathematics encompasses geometry, algebra, number theory, combinatorics, cryptography, analysis, topology, and so on. Remember, mathematics is simply mathematics. A mathematics major is not anything outside of mathematics. A mathematics major will not teach you how to write PyTorch, configure CUDA, build ResNet from scratch, or train and tune Transformers. Furthermore, it will not teach you classical machine learning, classical control theory, or classical aerospace fluid dynamics and finite element methods—because these are not mathematics at all, and do not belong to mathematics. And don't believe statements like "studying mathematics allows you to easily switch to any other major" or "mathematics is the mother of all majors."