The Kalam Argument, according to William Lane Craig goes:
The first thing to notice is that there are two premises and one conclusion. Also notice that the conclusion is undeniably true given that the premises are true. However, one may ask about why the first two premises are true...
Premise 1: “If the universe began to exist, then the universe has a cause of its beginning” (Craig, 2015).
As William Lane Craig says, “To claim that something can come into being from nothing is worse than magic. When a magician pulls a rabbit out of a hat, at least you’ve got the magician, not to mention the hat!” (Craig, 2015). Scientific evidence and our everyday experiences show that this is true. Quantum mechanics does not contradict this, as Randy Everist states, “Quantum mechanics does not in fact posit something coming from nothing, but rather things coming from the quantum vacuum–which is not ‘nothing.’” (Everist, 2016)
Premise 2: “The universe began to exist” (Craig, 2015).
According to Craig, “if an actually infinite number of things could exist, then various absurdities would result.” (Craig, 2015). To show this, let’s look at Hilbert’s hotel, by the mathematician David Hilbert. Hilbert’s hotel has an infinite number of rooms that are full. However, the hotel manager can still accept a new guest by moving each person one room number up (room 1 to room 2, room 2 to room 3, room 3 to room 4, etc.), leaving room 1 open. The hotel can even accept an infinite number of guests by doubling each person’s room number (room 1 to room 2, room 2 to room 4, room 3 to room 6, etc.), leaving an infinite number of odd hotel rooms open. Also, an infinite number of past events cannot exist, since you cannot count up from negative infinity to zero.
Scientific evidence also points to the universe having a beginning. For example, the Big Bang model states that space-time is like a cone. If you go far enough back in time, you will reach a singularity. Going back in time beyond that is impossible because there is nothing beyond that point. Craig says the following about the beginning of the universe:
The Borde-Guth-Vilenkin theorem proves that classical space-time, under a single, very general condition, cannot be extended to past infinity but must reach a boundary at some time in the finite past. Now either there was something on the other side of that boundary or not. If not, then that boundary just is the beginning of the universe. If there was something on the other side, then it will be a region described by the yet-to-be discovered theory of quantum gravity. In that case, Vilenkin says, it will be the beginning of the universe. Either way, the universe began to exist. (Craig, 2015)
Also, the Second Law of Thermodynamics shows that the universe approaches equilibrium, a “heat death”. If the universe was infinite, the “heat death” would be the current state of the universe. Ludwig Boltzmann suggested that the universe that we live in is a small region of disequilibrium. However, using Boltzmann’s hypothesis, it would be much more likely to have a small region of disequilibrium (just the solar system) rather than a bigger region (the entire universe), which suggests “a strange sort of illusionism: in all probability we really do inhabit a smaller world, and the stars and the planets we observe are just illusions, mere images on the heavens” (Craig, 2015).
Conclusion: “Therefore, the universe has a cause of its beginning” (Craig, 2015).
This cause must be:
Some people question about the cause of God, stating that it is special pleading to say that God doesn’t need a cause. However, as stated before, God doesn’t require a cause because he does not have a beginning. “The First Cause’s act of bringing the universe into existence is the first moment. Hence, if the First Cause was not really the first cause after all, then the first moment of time would already have existed. But it did not exist. Hence, the First Cause was the first” (Everist, 2016).
Craig, W. L. (2015). The Kalam Cosmological Argument. Lecture presented in University of Birmingham, Birmingham. Retrieved September 23, 2018, from https://www.reasonablefaith.org/writings/popular-writings/existence-nature-of-god/the-kalam-cosmological-argument/
Everist, R. (2016, October 20). 11 objections to the kalam cosmological argument [Blog post]. Retrieved from https://crossexamined.org/11-objections-kalam-cosmological-argument/
Lam, T. (n.d.). Introduction to Philosophy. Retrieved September 23, 2018, from https://courses.lumenlearning.com/sanjacinto-philosophy/chapter/cosmological-argument-objections-and-counterarguments/