The cosmos is the universe considered as an integrated orderly system. Sometimes the cosmos is the orderly part of a larger whole, the other part being chaos. Any account of the origin of the universe as a whole, whether based on

myth,religion, philosophy, or science is a cosmogony.

An account of the nature and origin of the universe that is systematic is a cosmology. This term is used for the particular branch of physics that considers this question, and also for inquiries of a more philosophical nature. Cosmological arguments for the existence of God begin with very general facts about the known universe, such as

causation,movement, and contingency,and then argue that God must exist, as first cause, or unmoved mover,or necessary being, to account for these facts. The first two ways of proving the existence of God listed by St. Thomas Aquinas are cosmological arguments.