One of my favorite arguments for God’s existence is called the Kalam Cosmological Argument (KCA). It consists of two premises that lead to a logically deductive conclusion with significant theistic implications. The syllogism goes as follows:
1- Whatever begins to exist has a cause.
2- The universe began to exist.
3- Therefore, the universe had a cause.
Let’s begin by evaluating the first premise: “Whatever begins to exist has a cause.” We see examples of this every day in our lives. Through the decay of uranium, lead is caused to come into existence, the car factory causes the car to come into existence, and your parents caused you to come into existence. This premise seems intuitively obvious and it is empirically supported.
Moreover, a primary metaphysical principle states, “out of nothing, nothing comes.” Consider the fact that if something could come from absolutely nothing, then anything and everything could come from nothing at any time. Nachos, music, and wookies should just pop into existence out of nothing every day! If something can actually come from literally “no thing,” then why can’t anything or everything come into being from nothing? Why is it just universes? “What is it about nothingness that makes it so prejudiced against everything else but universes?” Obviously, this is a premise that is self-evident. William Lane Craig summed up the first premise by saying:
“The first premise is intuitively obvious once you clearly grasp the concept of absolute nothingness. You see, the idea that things can come into being uncaused out of nothing is worse than magic. At least when a magician pulls a rabbit out of a hat, there’s the magician and the hat. But in atheism, the universe just pops into being out of nothing, with absolutely no explanation at all.”
Since we have established the rationality of the first premise, let’s examine the second: “The universe began to exist.” One common argument against premise (2) is that the universe did not begin to exist but has always been here. Is this logically possible or even scientifically accurate?
Philosophy of Infinity
One philosophical argument promoting this premise involves the logical impossibility of creating an actual infinite number of events in physical space and time to exist. For example, if you start counting 1, 2, 3… you could count forever and never reach a time when you complete counting to infinity. You could count forever, but whatever number you were counting at that precise moment would be an actual finite number. You can always add one more to the number you were currently saying; therefore, you could never reach the end of infinity.
So, is there such a thing as infinity future? Yes, but it will never get here. Is an infinite past possible? If the universe did not begin to exist, then it had to have always been here from past infinity, but then the number of events that happen in the universe would have to be infinite because the universe would be infinite. It would then be impossible to answer many questions. For instance, consider al-Ghazali’s thought experiment regarding two beginningless series of coordinated events. He encourages us to envision our solar system existing from infinity past. The planet’s orbital periods would correspond that for every one orbit Saturn would complete, Jupiter would complete 2.5 orbits around the sun.
Here’s the rub: if both Saturn and Jupiter have been orbiting the sun from infinity past, which planet has completed the most orbits? Initially, you might want to answer Jupiter because it is closer to the sun and orbits 2.5 times faster, but you would be mistaken. If both planets have been orbiting from infinity past, the correct mathematical answer would be that Jupiter and Saturn have completed the exact same number of orbits. This is ludicrous because Jupiter orbits 2.5 times faster than Saturn, and it would seem that if they have been orbiting the sun from infinity past, then, Saturn should have fallen infinitely behind Jupiter. This is a ridiculous paradox demonstrating the absurdity of an actually infinite past. Since this is absurd, it is logically evident that the universe did begin to exist, and is therefore, not actually infinite.
As I demonstrated earlier, it is impossible to reach an actually infinite future through successive addition because we can always add one more to any number we are currently counting. The same is true when considering the infinitude of the past while counting down backwards through the negative numbers. But, if it were possible to have a past infinity, then the current moment of right now would never be here. Just as it is impossible to count one number at a time and complete an actual infinity, it is just as impossible for an actual infinite amount of moments to exist in the past and be completed today at this present moment.
Comparatively, this idea would be analogous to affirming the proposition that one could jump out of an infinitely tall bottomless pit. This would be logically impossible, even for a superhero with infinite jumping power, as there is no foundation for him to jump from. Since the present moment is real, and we are really here right now, then, logically, it had to have been preceded by a finite past. Therefore, there must have been a first event, and the universe began to exist.
If the universe began to exist, the conclusion logically follows: “Therefore, the universe has a cause.” Using logic alone, we can prove that time and space began to exist. But perhaps your philosophy is that you don’t like philosophy. That’s no problem, we also have much scientific data that will support the truth of premise (2): “The universe began to exist.” In my next article I will examine the scientific data supporting this specific premise and the Kalam’s deductive conclusion.
 William Lane Craig said this while I was a student in his classroom (an experience I will never forget)!
 William Lane Craig, by Lee Strobel, The Case for a Creator (Grand Rapids, MI: Zondervan, 04), 99.
 William Lane Craig, Key Philosophical Issues for Apologists: course notes, Biola University, 2012, (28)