我们生活在一个系统之中。系统无所不在,其大无外,其小无内。从大里说,整个宇宙就是一个系统,这个系统由若干要素组成,即各个银河系。每一个银河系又成为一个系统,相对宇宙来说,这每一个银河系构成的系统都是一个子系统。在这个子系统里也包含若干要素,即各个星系。各个星系是银河系的构成要素,同时又是一个系统,也是银河系的子系统,依 We live in a system. The system is ubiquitous, its large and small, its small no. From the inside, the entire universe is a system composed of several elements, namely the various galaxies. Each galaxy becomes a system, and each galaxy constitutes a subsystem relative to the universe. In this subsystem also contains a number of elements, that is, each galaxy. Each galaxy is a component of the Milky Way and at the same time a system of subsystems of the Milky Way,