Ordinarily seven steps, phases, periods or levels in a complete cycle, gamut or process. This makes sense when considering so many things are not "things" but processes or cycles of evolution. Processes and cycles can be divided into seven steps or phases each having its own peculiar characteristics - especially in relation to each other. Music is a good example where there are seven main tones to an octave - the eighth step is to the next octave. Each tone interval is unique in its qualities when related to the other tone intervals.
Dr. H. Spencer Lewis wrote considerably concerning the seven stages, steps or periods of universal cycles.
Reich looked at cycles as having four main steps or phases.
Ancient and sacred texts are filled with references to seven.