This book is a summary of Song Lao, an academician of the Chinese Academy of Sciences and Chinese Academy of Sciences, in his research field. From the two dimensions of history and foreign exchanges, it sorts out the context of Chinas scientific development vertically and horizontally. The whole book describes the process of Chinese science development in five major fields, including classic figures, environmental protection, population control theory, history of Chinese science, and foreign exchanges in the field of science. Many viewpoints and formulas are summarized by Mr. Song in his long-term scientific research work It has very precious inheritance value. The main features of this book are: establishing the partial differential equation of the optimal field and its boundary conditions, and theoretically solving the problem of the fastest control of the linear system; And proved the law of two-way limit of population fertility.