Cosmology

Abstract

Abstract Cosmology is the study of the universe as a whole, including its origin and ultimate destiny. From a Christian point of view, any complete cosmology must culminate in the assertion of God's creation of the universe ex nihilo (“out of nothing”). Indeed, the cosmological argument — perhaps the central argument of natural theology — holds that there is no way to explain the existence of the universe apart from an appeal to God as its first cause. But there are various ways in which this claim has been interpreted. According to the kalam version of the cosmological argument, it can be established by both philosophical and scientific arguments (especially the Big Bang model of cosmic origins) that the universe must have had a beginning in time, and that there must have been a cause of this beginning. However, other versions of the argument, such as those associated with Thomas Aquinas, hold that whether the universe had a temporal beginning or not is irrelevant to whether it was created by God. According to the first of Aquinas's Five Ways, that anything in the universe undergoes motion or change at all — even if the series of moving or changing things extends infinitely into the past — is only explicable if there is a first unmoved mover, altogether outside of time and space, who sustains the motion or change of the entire infinite series. The Second Way argues that the sequence of causes and effects existing within the universe, even if it has no beginning in time, must be explained in terms of a first uncaused cause that, again, sustains the whole infinite causal series. The Third Way (the last of the Five Ways constituting a cosmological argument) holds that even an infinite sequence of things which come into being and go out of being must be explained by reference to a necessary being, one which has always existed and cannot fail to exist.