This paper inherits and develops Newton's dialectical space-time concept. Physical matter is an objective existence with energy. Moreover, physical matter can be divided into solid matter and field matter. Vacuum space is the absolute space, and the speed of field matter in vacuum is a constant C. In this paper, general mass is introduced and defined based on energy. For any physical matter with energy E, its general mass is defined as mE = E/C2. The introduction of general mass extends Newton's classical dynamics from solid matter to field matter and Newton’s classical law of gravitation to the law of general gravitation, which replaces Einstein's special and general relativity. Furthermore, a verification experiment of the law of general gravitation is presented in this paper. When the light is far from the sun’s atmosphere and R = 200R0, the light deflection angle Δθ is 0.004367u2033. Regarding standard cosmology problems, the general mass of field matter is the so-called dark matter, and the energy of field matter is the so-called dark energy. The universe expands uniformly around the void space at the field speed C, with the expansion of galaxies accelerating. The estimated values of the general mass and energy of the field matter are approximately consistent with the modern cosmic observation data. Energy is the essence of physical matter, and inertia, gravitation, space and motion characteristics are the universal fundamental properties of energy, and Inertial mass, gravitational mass, time and temperature are the measurements of the properties of energy.