A cosmological argument for the existence of God is an argument that the very existence of the universe and its nature demand God’s existence. The argument presented here is a form of the cosmological argument that originated in the philosophy of Plato and Aristotle and was refined by Thomas Aquinas. With the advances of modern science, the version I will provide will be perhaps clearer for some than the form set forth by Aquinas. It is a composite of Aquinas’ vertical cosmological argument and the Kalam cosmological argument:

1. Everything that has a beginning needs a cause.
2. The universe had a beginning.
3. The universe needs a cause.
4. There cannot be an infinite regress of caused causes.
5. There must be a cause for all else that has no beginning and needs no cause for its own existence.

Premise #1 is self-evident. A thing cannot bring about its own existence since it cannot be before itself. But if it began to exist, it cannot have popped into existence from nothing and from nowhere; nothing produces nothing.

There are several pieces of evidence that support the contention of Premise #2 that the universe had a beginning. The scientific community has long since accepted the beginning of the universe via the big bang.  To quote from Norman Geisler, “Logically and mathematically, the evidence for the big bang suggests that originally there was no space, no time, and no matter.” (Geisler, 1999)  Here are some much-summarized points to demonstrate why the universe is thought to have begun, most of which was set forth by astronomer Robert Jastrow (Jastrow, 1982), and some of which has been subsequently discovered:

1. The second law of thermodynamics shows that usable energy is running down, which means there had to be a time when the process started. If not (if there was an infinite amount of time before now), all the energy in the universe would have been used up, and we would not be here.
2. The universe is expanding. Traced backward, there would have to be a place it started to expand.  The universe cannot be continually expanding and retracting since it would eventually run out of energy and collapse on itself.
3. If the universe were eternal, time would also be eternal. But we could never have gotten to this point if time were infinite. Time measures the intervals between movements. There was no movement until the universe began, therefore there was no time. It would be impossible to traverse an infinite amount of time.
4. We see matter continually degrading rather than becoming more complex. If things fall apart when left to themselves, the world could not be infinite. It would already be destroyed. Only that which is self-sufficient and self-sustaining can be infinite.
5. There is a radiation “echo” throughout the universe which scientists at first thought was merely static or a malfunction of their equipment. This emanation of radiation is consistent with what would be expected of an enormous explosion in the past, down to the wavelength that should be produced by such light and heat.
6. After the big bang theory became the predominant view of the universe’s origin, scientists began looking for a large mass of matter associated with the original explosion, but none could be found until the Hubble made it possible to find it. One astronomer, Michael Lemonick said, “by peering back into the beginning of time, a satellite finds the oldest structure ever observed—evidence of how the universe took shape 15 billion years ago.” (Lemonick, 1993) This was exactly what they were looking for if the theory were to be shown to be true beyond a reasonable doubt.

Premise #3 is true by the laws of logic if the first two points are true. I will quote a fellow student, Glenn Smith, on this point: “Everything we currently observe depends on something else. This includes sub-atomic particles, our planet’s atmosphere, the sun, and everything observable. If it weren’t for our atmosphere, you and your computer would vaporize. So if everything in the universe is currently dependent, the whole universe is currently dependent.”

Premise #4: One cannot posit an unending string of caused causes. This just seems obvious, but if you need some reasons why this is so, I will try, though it seems the more obvious something is, the more difficult it is to explain. If the causes of the universe itself needed a cause, and the cause of that cause needed a cause, ad infinitum, the string of causes could never be put into motion. An infinite series is impossible because one more moment (or cause) could always be added. But it is impossible to add to an infinite. Plus, if there were an infinite number of causes, there would be an infinite number of moments in which the act of causation took place. But if there were infinite moments, the current moment could have never arrived, since it is impossible to traverse an infinite number of moments. Quantitative infinity is merely a convention of mathematics but has no metaphysical counterpart. Without a first cause, there is no causality in the series.

Conclusion (#5): If the universe needs a cause for its existence, and there cannot be an unending string of contingent causes, there must be a Cause whose existence is necessary. (“Necessary” is used in opposition to “contingent,” in which a contingent being requires a cause for its existence, and a necessary Being has no cause, and no beginning.) Something must be eternal for anything else to exist. For nothing produces nothing. If nothing ever existed, then nothing could exist. But the universe, as you have seen, is not eternal; it began to exist. So, there must be something else, or someone else, who does not depend upon any other for existence but exists by virtue of itself.  This is beyond human understanding (because we have never experienced anything that is beginning-less), but it is not contradictory to logic for there to be a being without a beginning. As I hope to have shown, no other state of affairs is possible, for if something is not eternal, then nothing could have ever existed at all.

This has been a brief account of the cosmological argument. It has not taken into consideration certain objections. These objections are dealt with well in Norman Geisler’s Baker Encyclopedia of Christian Apologetics in the article “Cosmological Argument.”  This argument does not, in itself, produce the Christian God, but leads to it if one follows all of the implications and other evidence for the God of the Bible, which cannot be provided in one article. This argument is merely an attempt to show that there is a Supreme Being to which the universe owes its existence.

Sources

• Geisler, N. (1999). “Kalam Cosmological Argument.” In Baker Encyclopedia of Christian Apologetics (p. 400). Grand Rapids: Baker Books.
• Jastrow, R. (1982). “A Scientist Caught Between Two Faiths: Interview with Robert Jastrow.” Christianity Today.
• Lemonick, M. D. (1993). Echoes of the Big Bang. Time.