This article applies the knowledge of set in mathematics to study binary oppositions, and deduces that consciousness changes a thing through its opposite. The author assumes that a life’s flash forms a spherical divergent field; the center of the field is the material world perceived by the life; the field is space generated by the propagation of flash. So this article reveals the origin of space. When the propagation mode of flash is applied to mass, the formula for universal gravitation is derived, which confirms the rationality of the above hypothesis. When the propagation mode of flash is applied to static electricity, Coulomb’s law is derived, which also confirms the hypothesis. Therefore, universal gravitation and Coulomb force are essentially manifestations of flash propagation.