Abstract. Conventional work on scienti c discovery such as BACON derives empirical law equations from experimental data. In recent years, SDS introducing mathematical admissibility constraints has been proposed to discover rst principle based law equations, and it has been further extended to discover law equations from passively observed data. Furthermore, SSF has been proposed to discover the structure of a simultaneous equation model representing an objective process through experiments. In this report, the progress of these studies on the discovery of rst principle based scienti c law equations is summarized, and the future directions of this research are presented.