The deceptive simplicity of William Lane Craig’s Kalam Cosmological Argument

As regular viewers, listeners, and readers of Premier Unbelievable well know, some much-debated topics within the field of philosophy are: whether or not there is a God, if we can prove this using philosophical reasoning, and, assuming we can, how much are we actually able to discern about this cosmic deity. This process of thinking and making logical deductions about God without the need for “revelation” is called Natural Theology: using ‘God given’ powers of reasoning to learn about, or determine the existence of, a divine creator. This field is, depending on who you ask, the greatest ally or greatest enemy of so called “revealed theology,” information about God given to us from God himself. One’s personal beliefs concerning God will largely determine opinions about these two fields of study, however they are both rich historical tapestries of great scholarship, and, as we shall soon see, not as mutually exclusive as one may think.

It is my intent in this article to discuss a small fraction of these subjects, namely Dr William Lane Craig’s take on the “Kalam Cosmological Argument,” and its surprising use of Zeno and the rejection of actual infinites (the possibility of something of an infinite nature to actually exist).

The pre-Socratic Greek philosopher Zeno came up with an often-misunderstood thought experiment to learn about the nature of infinity. Does infinity exist? Is it impossible? What are the consequences of infinity? Confusingly, Zeno begins this train of thought by thinking about motion. Even more confusingly, the logical conclusions he comes to have far reaching universal and theological consequences.

This is Zeno’s hypothesis:

The legendary hero Achilles has agreed to race a common tortoise. Knowing his speed and stamina to be greater than that of any tortoise, Achilles agrees to give the tortoise a head start. Now the paradox begins. Achilles’ goal is to overtake the tortoise, however, to do so, he must first travel the distance the tortoise has moved while he was still. However, this time, the tortoise has moved forwards. Now Achilles must travel that distance, and yet the tortoise has moved forwards. It is Zeno’s logical conclusion that Achilles will never overtake the tortoise, because, to do so, he must overcome an infinite series of incremental advances by the tortoise.

This was Zeno’s illustration, but without an overtime shift at the brain factory, it’s fairly difficult to understand what this has to do with anything other than bizarre antiquarian sports. I find it easier to understand when the tortoise is removed from the picture.

Achilles is running from point 0 to point 1. However, to reach point 1, he must first reach point 0.5, halfway. Yet, he cannot reach point 0.5 without reaching point 0.05, the next halfway point, and so on and so forth, navigating an infinitely divisible sequence of halfway points, each more minute and more annoying than the last. This is the clearest iteration of the paradox, how can movement through an infinite sequence happen to reach a finite goal. Zeno’s illustration is mathematically and logically sound, yet renders any movement impossible. How can this be?

Nobody would doubt, however, that numerical infinity exists. There is an infinite number of numbers, fractions, and even prime numbers (everyone’s favorite kind). Therefore, Zeno rejects actual infinities, negating them to the theoretical. This is Zeno’s paradox.

Read more:

It is time to move on from Richard Dawkins

Why is there something rather than nothing?

How do we know God is real?

To illustrate another way: how can you ever get older if, to get from 35 to 36, you need to have been at every decimal age between the two integers (35.999999999999999999… goes on forever and is thus not surmountable in a linear sequence such as aging).  

A third and final illustration to support the idea that infinities cannot exist in our material universe was posed by the famous William Lane Craig.

Dr. Lane Craig’s Argument goes like this:

If one were to walk into a library holding an infinite number of red books, and an infinite number of green books, as well as an infinite number of librarians weeping on the floor, you run into a problem. If the number of red books is infinite, and as is the number of green books, then the sum of all the books in the library must be:

R (red books) = ∞

G (green books) = ∞

∞(r) + ∞(g) = ∞

It cannot be that the sum of two positive parts is equal to one of the parts. The sum of two things cannot be the same as one of the things. This is just as true when we treat infinity like another number, so therefore, infinity must be impossible to actualize in our material universe, it remains a purely mathematical concept (excuse the excessive technical vocabulary, we do try to keep it brief).

Now, I can practically hear the reader shouting at the page “this is all well and fine good Sir, but what on earth does it have to do with God or proving his supposed existence?

Well, the first thing one must know about Craig’s argument is that it is deductive. If both premises are true, the conclusion follows as necessarily true. All this talk about infinity only goes to assert that his premises are true. His syllogism (logical series of internally affirming statements to reach a logically necessary conclusion) goes as follows: 

1. Everything that began to exist has a cause.
2. The Universe began to exist.
3. Therefore, the Universe has a cause.

With this in mind, dear reader, you may now begin to see why it was so necessary to thoroughly debunk the idea of ‘actual infinities,’ because if we had not done so, the sceptic could have reasonably made the claim that the premises are incorrect, that the universe exists eternally, and play Dawkin’s advocate, mocking any notion of a “silly god” necessary to bring an eternal universe into existence.

However, we now know that an infinite universe, or even, as some like to suggest, an infinite cycle of universes perpetually destroyed and reborn is scarily identical to the actual infinity that we so ruthlessly relegated to theory. This latter idea is called an “infinite regress,” and, cosmologically (in terms of the nature of the universe), an infinite series of causes without a primary first cause is impossible, since an infinite set of causes, going back for eternity, never actually causes anything to take place, because it takes an infinite amount of time for the causation to take place, and none of the causes have the power to be the primary (un-caused) cause, they are all secondary intermediate, they only find their causal power from what has caused them, like a stone being thrown by an arm, creating a splash in water. The stone cannot throw itself, nor can it result from an infinite series of stones throwing each other.

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Many readers will have heard this argument, or similar logic in their previous dealings with the topic, but for an argument that has been ranked as “among the most sophisticated and well-argued [arguments for the existence of God] in contemporary theological philosophy” by one Dr Michael Martin, it is a matter worth coming back to.

There is certainly evidence to suggest that the niverse had a beginning, most notably, Edwin Hubble’s 20th Century astronomical observation that galaxies and stars were moving away from us (or, simply, observably moving. See: cosmic red shift), and that the universe was therefore expanding. Infinite expanse is impossible, as is an infinite ‘yoyo’ of expansion and contraction, the universe must have had a finite beginning.

The idea of the “Big Bang,” proposed by Fr. Georges Lemaître PhD (priest- physicist extraordinaire) in the 1920s has become the scientific norm since the discovery of cosmic background microwave radiation, leftover from this beginning, a singular point of intense density that gave rise to the universe. This superbly evidences the idea that the universe had a beginning. This is a widely held and respected cosmological standpoint. Its main competitor, the Steady State Theory, the idea that the universe is uncreated, does not have anywhere near the observational evidence of the Big Bang.

Dr Craig makes the argument that this first cause of the universe is God, and that a number of God’s properties can then be deduced rationally. This God must be uncaused, otherwise the impossibility of an infinite regress would take place, as we have discussed. Craig’s deduced God must therefore be outside of the rules of the created universe, like the hand that knocks down the first domino in a domino chain, it follows different ‘rules,’ thus allowing God to remain uncaused. This conclusion comes part and parcel with the fact that this God is timeless, and possessing powers greater than anything inside the universe, having the ability to create everything “ex nihilo” – from nothing.

If your cranium has not yet been reduced to a puddle of bubbling soup on the floor, Craig’s key development, however, is his proof of a personal creator, the idea that God is more than an inanimate entity like nuclear reaction that brings forth energy and changes the structure of atoms. God makes decisions, and this can be logically proven.

Because the universe did at one point not exist, this God has demonstrated non-deterministic agency: i.e. the belief that God has the ability to do things that are not pre-determined. A “decision” has taken place to put the universe into motion, therefore God must be personal, rather than creating without consciousness. It is conceivable that there could be a creator who creates in this way, whose creations are an inevitable by-product of its existence, in the same way chopping wood is an unconscious and inevitable by- product of a sharp saw. The God that Lane Craig argues for is more akin to the master Carpenter, consciously creating, rather than doing so automatically. This sets Craig’s argument apart from other so-called cosmological arguments (arguments for God’s existence based upon the nature of the cosmos), because he is able to deduce a personal God, more akin to the God of Craig’s own Christianity, than the mere existence of a god of any reasonable kind put forward by, for example, the Thomistic argument of Aquinas.

Finally, merely using Occam’s razor, the logical principle that the simplest explanation is most likely to be true, Craig is able to ascertain the singularity of this God, due to the simple fact that there is no logical reason presented for there to be any need for multiple uncaused creators. “Read it and weep, polytheism,” says William Lane Craig, in-between the lines.

Those are the main elements of William Lane Craig’s Kalam Cosmological Argument, Kalam being the name of a rational school of Islamic scholasticism that inspired Craig, taking its rationalism, of course, from pappa Aristotle. Because the universe exists, it must have a cause, as all things that exist do. This cause must be uncaused, because actual infinities are impossible, and personal, because it acted upon its own agency. Mic, proverbially, dropped.

Samuel Rogers is a sixth form student of theology in Liverpool, England.